UPDATE: Antiretroviral Therapy 

This guideline has been updated by section, with a date stamp for each section. As of September 2015, this guideline is under review. Please refer to the April 2015 update of the DHHS guideline for the most current information on antiretroviral therapy for adults.

What’s New — September 2015 Update
  • Section III: When to Initiate ART: With recent evidence supporting earlier initiation of antiretroviral therapy (ART), New York State now recommends that ART be initiated in all patients with a diagnosis of HIV infection.

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Antiretroviral therapy (ART) refers to the use of pharmacologic agents that have specific inhibitory effects on HIV replication. The use of less than three active agents is not recommended for initiating treatment. These agents belong to six distinct classes of drugs: the nucleoside and nucleotide reverse transcriptase inhibitors (NRTIs, NtRTIs), the non-nucleoside reverse transcriptase inhibitors (NNRTIs), the protease inhibitors (PIs), the fusion inhibitors (FIs), the CCR5 co-receptor antagonists, and the integrase strand transfer inhibitors (INSTIs). The commercially available antiretroviral drugs that are approved by the Food and Drug Administration (FDA) for the treatment of HIV/AIDS are listed in Appendix A.

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Updated March 2006; reviewed April 2015


Clinicians should prescribe an ART regimen that is best able to delay disease progression, prolong survival, and maintain quality of life through maximal viral suppression (see Table 1). (I)

The clinician should involve the patient in the decision-making process when determining whether to implement ART. The clinician should review the benefits and risks of treatment for each individual patient. (III)

Table 1: Goals of Antiretroviral Therapy
  • Maximal and durable suppression of viral replication (measured by viral load assays)
  • Restoration and/or preservation of immune function
  • Reduced HIV-related morbidity and mortality
  • Improved quality of life
  • Limitation of the likelihood of viral resistance to preserve future treatment option


In typical clinical practice, durable suppression of viral replication to undetectable levels may be achieved in approximately 80% of cases. The maximal suppression of viral replication is generally associated with gradual increases in the CD4 count and clinical stabilization or improvement of HIV-associated symptoms. When maximal suppression is not attainable due to the inability to construct an effective regimen for the patient, partial viral suppression (≥0.5 log reduction, or 3-fold, from baseline viral load value) and stable CD4 counts are reasonable alternative goals. However, incomplete suppression of viral replication may be associated with continued immunologic and clinical deterioration and the evolution of additional resistance mutations. Patients who are unable to adhere strictly to complex medication regimens are those most likely to develop HIV-drug resistance and to face limited future ART options (see Section IV: The Importance of Patient Adherence). The clinician needs to review the benefits and risks of treatment for each individual patient (see Table 2).

Table 2: Benefits and Risks of Antiretroviral Therapy
The benefits of ART include:

  • The preservation and/or restoration of immune function
  • Improvement of overall health and the prolongation of life
  • The suppression of viral replication
  • The possible decrease in risk of viral transmission to others (including fetal transmission)

The risks of ART include:

  • Adverse effects of the medications on quality of life
  • Known, and as yet unknown, long-term drug toxicities, including potential fetal toxicity
  • The development of HIV drug resistance to drugs currently available and possibly to those not yet available, which may limit future treatment options

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Updated September 2015


With recent evidence supporting earlier initiation of antiretroviral therapy (ART), New York State now recommends that ART be initiated in all patients with a diagnosis of HIV infection. This recommendation is based on evidence that patients with established HIV infection benefit from ART at all stages of disease and on recent data that demonstrate a dramatic reduction of HIV transmission risk from ART-treated patients.

Public health guidance currently recommends that all patients living with HIV be treated with ART to reduce transmission of HIV in a strategy commonly known as “treatment as prevention.” This Committee strongly supports the idea of treatment as prevention.

Table 3: Recommendations for Initiating ART
1. ART should be recommended for all patients with a diagnosis of HIV infection. (AI)2. Clinicians should strongly recommend initiation of ART for patients who present with any of the following conditions that increase the urgency of starting ARTa:

  • AIDS-defining condition (AI)
  • Pregnancyb (AI)
  • Symptomatic from HIV, including any of the following:
    • HIV-associated neurocognitive disorder (HAND)c (AII)
    • Severe thrombocytopenia (AII)
    • HIV-associated nephropathy (AII)
    • HIV-related malignancies (AII)
  • Chronic hepatitis B or C infectiond,e (AII)
  • Age 50 or older (AII)

3. Patients with seronegative partners should be counseled about the reduction of HIV transmission risk when effective ART is initiated; ART is strongly recommended in patients with seronegative partners. (AI)

4. Decisions to initiate ART should be individualized (see Section III. B), particularly for the following populations:

  • Long-term nonprogressorsf (AII)
  • Elite controllersg (AIII)
  • Patients with potential barriers to adherence (AIII)
a See Appendix B for evidence and ratings.
b For recommendations on initiating ART in HIV-infected pregnant women, refer to the DHHS Recommendations for the Use of Antiretroviral Drugs in Pregnant HIV-1-Infected Women for Maternal Health and Interventions to Reduce Perinatal HIV Transmission in the United States.
c HAND is currently used to encompass a hierarchy of progressive patterns of central nervous system involvement ranging from asymptomatic neurocognitive impairment (ANI), to minor neurocognitive disorder (MND), to the more severe HIV-associated dementia (HAD) (see Cognitive Disorders and HIV/AIDS).
d Initial ART regimens for patients with chronic hepatitis B must include NRTIs that are active against hepatitis B (see Hepatitis B Virus guidelines).
e In co-infected patients with HCV genotype 1 and CD4 counts >500 cells/mm3, some clinicians would defer ART until HCV treatment is concluded due to significant interactions between some antiretroviral agents and NS3/4A protease inhibitors used as part of hepatitis C therapy (see Hepatitis C Virus guidelines).
f Long-term nonprogressors demonstrate a lack of disease progression, marked by no symptoms and low viral loads in the absence of therapy during long-term follow-up. Most published studies of long-term nonprogressors include 7-10 years of follow-up (see Section III. B).
g Elite controllers suppress HIV to low but detectable levels (Section III. B).


Evaluation and preparation for ART initiation includes each of the following essential components:

Clinicians should refer patients for supportive services as necessary to address modifiable barriers to adherence. An ongoing plan for coordination of care should be established. (AIII)

Clinicians should involve patients in the decision-making process regarding initiation of ART. The patient should make the final decision of whether and when to initiate ART. (AIII)

When the decision to initiate treatment is made, ART should be prescribed and monitored by, or in consultation with, clinicians who have experience in managing ART. (AII)

Preliminary results from the START trial1 and increasingly strong cohort data show that untreated HIV infection leads to increased morbidity and mortality from both HIV-related and non-HIV-related conditions, even at high CD4 counts. Together with the dramatic reduction of transmission risk with effective treatment, these data support the initiation of ART regardless of CD4 count in all adequately prepared patients, including patients diagnosed with acute HIV infection (for more discussion see Diagnosis and Management of Acute Infection). Patients in care who are documented long-term nonprogressors or elite controllers are a group that may warrant special consideration (see Section B: Deferring ART). Patients with chronic infection and higher CD4 counts are at low risk for short-term adverse outcomes, allowing time for proper assessment, education, and engagement of the patient in the decision to treat.

In START, a randomized trial initiating ART in treatment-naïve patients with CD4 counts >500 cells/mm3 versus waiting for a decrease to ≤350 cells/mm3 before initiation showed a 53% reduction in serious illness and death in the early ART group.1 Data from NA-ACCORD, a large observational cohort study, showed that both morbidity and mortality were improved by initiation of ART in patients with CD4 counts in the high or even normal range.2 A significantly decreased risk of death was observed in patients who initiated therapy at CD4 counts >500 cells/mm3 compared to those who deferred to 3, as well as in the cohort who initiated ART in the 350-500 cells/mm3 range compared with those deferring to 3.2 Although other cohort studies demonstrated only a minimal survival advantage3 or no survival advantage among those starting ART at the highest CD4 counts, they did confirm the benefits of initiating ART at levels ≤500 cells/mm3.4-6 Another showed an approximately 33% reduction in the risk of death from end-stage liver disease, non-AIDS infections, and non-AIDS-defining cancers with each 100 cells/mm3 increase in CD4 count.7 A randomized study of early versus deferred therapy in patients with CD4 counts in the 350-550 cells/mm3 range showed no mortality benefit8; however, this study has significant limitations, most notably a relatively brief follow-up period.

Accumulating evidence suggests that patients who initiate ART earlier or spend less cumulative time with detectable plasma viremia are less likely to suffer certain complications, such as cardiovascular disease,7,9-12 neurocognitive dysfunction,13-16 and some non-HIV-related malignancies.17-20 Cohort data also demonstrate that although older patients are likely to achieve virologic suppression, they are less likely to achieve an immunologic response, as measured by an increase of CD4 count by 100 cells/mm3, and that patients >55 years old may be at higher clinical risk even after starting therapy.21 The poor immunologic recovery seen in older patients is associated with higher morbidity and mortality, particularly cardiovascular events.22 In one study, men ≥50 years of age who initiated ART with CD4 counts in the 351-500 cells/mm3 range were able to achieve similar immunologic responses as younger men who initiated at lower CD4 counts.23

Studies have shown that, for HIV-infected pregnant women, the administration of ART during pregnancy and/or intrapartum significantly reduces the risk of mother-to-child transmission (MTCT) of HIV.24,25 In addition, a large study showed a 96% reduction in transmission between serodiscordant heterosexual couples when the positive partner was receiving ART,8 adding to the body of evidence that lower viral load reduces transmission risk. ART is now part of the established strategy aimed at reducing HIV transmission and is an essential component of prevention interventions along with risk-reduction counseling, safer-sex practices, and avoidance of needle-sharing. Although the majority of patients both in New York and worldwide present later in the course of their HIV infection,26-28 ongoing efforts to offer universal HIV testing to all 13- to 64-year-old patients may begin to identify patients earlier in their disease who can benefit from immediate treatment.

Key Point:
For HIV therapy to be successful over time, the initiation of ART should involve both the selection of the most appropriate regimen and the acceptance of the regimen by the patient, bolstered by education and adherence counseling. All are critical in achieving the goal of durable and complete viral suppression.


The CEI Line provides primary care providers in New York State the opportunity to consult with clinicians who have experience managing ART. The CEI Line can be reached at 1-866-637-2342 or 1-585-273-2793.The AIDS Institute maintains a voluntary HIV Provider Directory to assist with identification of experienced providers in New York State. Experienced providers can also be identified through the American Academy of HIV Medicine (AAHIVM) and the HIV Medicine Association (HIVMA).

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A. Counseling and Education Before Initiating ART


Counseling and education should include the following:

  • Basic education about HIV, CD4 cells, viral load, and resistance (AIII)
  • Available treatment options and potential risks and benefits of therapy (AIII) (see Table 4)
  • The need for strict adherence to avoid the development of viral drug resistance (AII) (see Section IV: The Importance of Patient Adherence)
  • Use of safer-sex practices and avoidance of needle-sharing activity, regardless of viral load, to prevent HIV transmission or superinfection (AIII)

Clinicians should involve the patient in the decision-making process regarding initiation of ART. (AIII)

Discussion of ART should occur at the start of care for all HIV-infected patients, regardless of CD4 count. The clinician and patient should discuss the benefits of early ART (see Table 4) and individual factors that may affect the decision to initiate, such as patient readiness or reluctance and adherence barriers. Clinicians should involve the patient in the decision-making process regarding initiation of ART.29 When clinicians and patients engage in shared decision-making, patients are more likely to choose to initiate ART and to achieve an undetectable viral load.30 Misconceptions about treatment initiation should be addressed, including the implication that starting ART represents advanced HIV illness. Initiating ART before symptoms occur allows patients to stay healthier and live longer.

Patients who do not have health insurance may qualify for Medicaid or the NYSDOH HIV Uninsured Care Programwhich provides access to free health care (HIV drugs, primary care, home care, and the ADAP Plus Insurance Continuation Program, or APIC) for residents who are HIV-infected but uninsured or underinsured. The program is open Monday-Friday, 8:00AM-5:00PM and can be reached: in state 1-800-542-2437; out-of-state 1-518-459-1641; TDD 1-518-459-0121.If eligible, patients may also consider treatment options through enrollment in clinical trials. A resource that may help with this process is the AIDS Clinical Trials Information Service (1-800-TRIALS-A,


Table 4 outlines the risks and benefits of early ART to discuss with patients when making the decision of whether and when to initiate ART.

Table 4: Benefits and Risks of Early ART in Asymptomatic HIV-Infected Patients
(early therapy = initiation at CD4 counts >500 cells/mm3)
Benefits of early therapy

  • Earlier treatment reduces both HIV-related and non-HIV-related morbidity and mortality1,2,7,10,18,31-34
  • Delay or prevention of immune system compromise35
  • Possible lower risk of antiretroviral resistance36
  • Decreased risk of sexual transmission of HIV*8,37-39

Disadvantages of early therapy

  • Potential drug-related reduction in quality of life in otherwise asymptomatic individuals40-42
  • Possibility of greater cumulative side effects from ART43
  • Possibility for earlier development of drug resistance and limitation in future44 antiretroviral options if adherence and viral suppression are suboptimal
  • Possibility for earlier onset of treatment fatigue
  • Higher prescription drug costs for the individual
* The risk of viral transmission still exists even when the plasma viral load is undetectable; ART is not a substitute for primary HIV prevention measures (e.g., avoiding sharing needles, practicing safer sex).45

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B. Deferring ART


In patients with advanced HIV (or AIDS), ART should be initiated even if barriers to adherence are present. In these cases, referrals to specialized adherence programs should be made for intensified adherence support (see NYSDOH Linkage, Retention, and Treatment Adherence Initiative). (AII)

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Potential Barriers to Adherence

Except in cases when initiation of treatment is urgent (see Section C: Initiating ART Following Acute Opportunistic Infections), clinicians should educate and prepare patients before initiating ART in those with potential barriers to adherence, including active alcohol or drug use; lack of insurance, transportation, or housing; depression; mistrust of medical providers; or a poor social support system. (AIII)

Although the current first-line regimens used for ART are much easier to tolerate with fewer side effects than earlier combinations, they are not free of side effects. Their use requires a lifelong commitment from the patient. Patients who prefer not to take medication, or who do not understand the significance of skipping doses, are at high risk for poor adherence and subsequent viral resistance. Except when initiation of treatment is clinically urgent, more than one visit before initiating ART is advisable to ensure adequate understanding of the importance of adherence and to address potential barriers or impediments to therapy. These may include but are not limited to active alcohol or drug use; lack of insurance, transportation, or housing; depression; mistrust of medical providers; or a poor social support system. These barriers should not necessarily preclude initiation of ART; some may not be completely modifiable before starting therapy and will require ongoing attention and use of supportive services throughout the course of therapy.

Patients who are at high risk for poor adherence may benefit if initiation of ART is temporarily deferred while further patient education efforts are undertaken (see Section IV: The Importance of Patient Adherence). In these patients, the risk of viral resistance and eventual treatment failure may outweigh any clinical benefit from earlier treatment before strict adherence can be expected.44 These patients should remain under particularly close observation for clinical and laboratory signs of disease progression.46 ART should be initiated as soon as the patient seems prepared to adhere to a treatment regimen. In patients with advanced AIDS, it is appropriate to initiate ART even if some barriers to adherence are present. In these cases, referrals to specialized adherence programs should be made for intensified adherence support (see NYSDOH Linkage, Retention, and Treatment Adherence Initiative).

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Long-Term Nonprogressors and Elite Controllers

Decisions to initiate ART in long-term nonprogressors (AII) and elite controllers (AIII) should be individualized.

Clinicians should consult with a provider experienced in the management of ART when considering whether to initiate ART in long-term nonprogressors and elite controllers. (AIII)

Long-term nonprogressorsdemonstrate a lack of disease progression, marked by no symptoms and low viral loads in the absence of therapy during long-term follow-up. Most published studies of long-term nonprogressors include 7-10 years of follow-up.Elite controllers suppress HIV to low but detectable levels (
See Ref. 47 for further definition of these groups and their characteristics.


The role of early ART initiation in long-term nonprogressors or elite controllers is unclear. At this time, there are not enough data to recommend for or against initiation of ART in long-term nonprogressors and elite controllers. Close monitoring of CD4 count and viral load level may be an acceptable approach. Declines in CD4 count should prompt consideration of initiation of ART. Elite controllers have demonstrated CD4 cell increases after initiation of ART.48 Another study found higher rates of hospitalizations in elite controllers compared to treatment suppressed patients, particularly for cardiovascular and psychiatric conditions49; however, there were important limitations in this analysis and it does not provide definitive evidence in favor of treating this rare population based on current information.50 The clinician and patient should discuss the current data on the risks and benefits of early ART as well as individual factors that may affect the decision to initiate, such as patient readiness and reluctance, adherence barriers, CD4 cell count and viral load, comorbidities, age, and partner serodiscordance. If treatment is delayed, clinicians should counsel patients about the risk of HIV transmission to partners.

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C. Initiating ART Following Acute Opportunistic Infections


Clinicians should recommend that patients beginning treatment for acute opportunistic infections (OIs) initiate ART within 2 weeks of OI diagnosis (see next recommendation for exceptions). (AI)

Clinicians should not immediately initiate ART in patients with tuberculous meningitis or cryptococcal meningitis. (AI)

Consultation with a clinician with experience in management of ART in the setting of acute OIs is recommended.(AIII)

For all other manifestations of tuberculosis (TB), clinicians should initiate ART in HIV-infected patients as follows:

  • For patients with CD4 counts ≥50 cells/mm3: as soon as they are tolerating anti-TB therapy and no later than 8-12 weeks after initiating anti-TB therapy (AI)
  • For patients with CD4 counts 3: within 2 weeks of initiating anti-TB therapy (AI)

In a randomized study, patients who initiated ART at a median of 12 days from start of OI therapy had better outcomes, as measured by disease progression and death, without an increase in adverse events, compared to those who initiated ART at a median of 45 days from presentation.51 Although this study excluded patients with active TB, three randomized controlled trials in patients newly diagnosed with HIV and pulmonary TB have demonstrated a significant mortality benefit when ART was initiated during the first 2 months of starting anti-TB therapy and a further benefit when those who were severely immunocompromised initiated therapy in the first 2 weeks.52-54 Although antiretroviral agents and anti-TB medications can have overlapping toxicities, ART should be initiated within the first 8 to 12 weeks of starting anti-TB therapy. Patients with CD4 counts3 should receive ART within the first 2 weeks of initiating anti-TB therapy.

Tuberculous meningitis and cryptococcal meningitis are exceptions; there are data showing that early initiation of ART increases adverse events and mortality in this setting.55-59 Close attention should be paid to possible drug-drug interactions between OI therapy and ART. In some cases, determining the optimal timing for initiating ART in patients with OIs can be complex and may require consultation with a clinician with experience in management of ART in this context.

After initiating ART, clinicians need to be alert to the possibility of immune reconstitution syndromes as CD4 cell counts are restored (see Immune Reconstitution Inflammatory Syndrome).

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Updated July 2004, currently under revision


A team approach to achieving adherence should be used. Nurses, pharmacists, peer counselors, caseworkers, and others who work in outreach, evaluation, and support of adherence should be involved. (III)

The clinician should assess treatment readiness prior to initiation of treatment, adherence readiness for subsequent regimens, and adherence at every clinical visit. (III)

Interventions should be intensified in times of decreased adherence.

Information about patients’ beliefs and attitudes should be communicated with all members of the healthcare team so that each provider can consistently address treatment adherence issues within the context of the overall treatment plan. (II)

If the patient is not fully committed to adhering to therapy, treatment should be delayed, and the clinician should continue to work on abating the patient’s concerns. Appropriate referrals should be provided for support groups, mental health, and drug treatment. (III)

Potential barriers to adherence include:

  • Communication difficulties that arise when the patient’s attitude about disease and therapy is different from that of the provider’s. Without open and nonjudgmental communication from the healthcare team, patients may not trust or may misunderstand the prescribed regimen.
  • Language or literacy barriers.
  • Unstable living situations (including limited or absent social support).
  • Discomfort with disclosure of HIV status, which may become known when medications are taken.
  • Inability to set long-term goals.
  • Inadequate knowledge about disease and effectiveness of medications or healthy living, including a patient’s lack of belief in his/her ability to take medications regularly.
  • Difficulty accessing adequate health care.
  • Housing, food, lack of childcare, or other immediate life needs, which are viewed as more pressing than taking the medications regularly.

Strict adherence to ART is essential for maintaining treatment benefit and preventing the development of HIV resistance. Study results are clear on the importance of a high level of adherence for good virologic control. Adherence to >95% of PI doses has been correlated with sustained viral suppression in several studies. Good adherence frequently wanes over time, and patients may need significant support the longer the duration of therapy.

Evidence from several studies suggests that patients who are confident about the efficacy of their treatment are more likely to adhere to their medication regimen and their healthcare visits. Confidence contains two significant components: understanding and belief.

Helping the patient understand the importance of treatment may be accomplished through a wide range of patient education activities, and especially through participation in peer education programs (see Section C: Educating the Patient About Adherence).

Encouraging belief in the efficacy of the regimen may be more challenging for the clinician and entails asking the patient what they believe about the causes of their disease and how it may be treated. Similarly, their opinions about what has contributed to the success or failure of their adherence to treatment should be sought (see Section D: Patients’ Beliefs and Attitudes).

For further guidance on assessing and promoting adherence, refer to Promoting Adherence to HIV Antiretroviral Therapy: Best Practices from New York State.

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A. The Patient-Healthcare Team Relationship: Involving the Patient

The quality of the relationship between the patient and the clinician greatly influences adherence. A trusting, open, and nonjudgmental relationship will improve the likelihood of strict adherence.


  • The healthcare team should promote active patient involvement in decision-making about initiating and managing ART regimens. The patient’s opinion of successes and challenges in maintaining adherence should be sought at routine visits.
  • A treatment plan should be negotiated, and active patient participation in the development of the treatment plan should be encouraged. Patient concerns and questions regarding the regimen should be elicited, and an individualized schedule should be made based on the patient’s lifestyle. A plan should be made for changes in routine (e.g., weekends, holidays, travel).
  • Patient trust should be established and a strong working relationship should be developed.
  • Questions regarding adherence should be open-ended and should be asked in a nonjudgmental manner with an understanding of the difficulty patients will have in admitting to adherence problems.
  • Members of the healthcare team should be open and accessible. Ways for patients to reach medical team members 24 hours/day when questions or concerns arise should be made available.
  • Intensive support should be provided to patients beginning medication regimens. Team members should meet with the patients frequently (or speak by phone) to provide encouragement, assess tolerability, assess adherence, and answer questions.

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B. Barriers to and Predictors of Adherence

The factors involved in adherence are complex. Age, race, sex, education level, and socio-economic status are not independent predictors of adherence. Although active substance use may affect adherence, a past history of substance use does not correlate with poor adherence (see Section E: Substance Use and Adherence). There is also a poor correlation between medical clinicians’ prediction of adherence and actual levels of adherence.


  • The healthcare team should be familiar with predictors of poor adherence and should address these issues in a caring and nonjudgmental manner.
  • Possible psychosocial factors and barriers to adherence, such as inadequate housing, active substance use, depression, or other mental health issues, should be addressed. Identifying patient-specific barriers to adherence will help determine which interventions are most appropriate.

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C. Educating the Patient About Adherence


  • To foster understanding of the importance of adherence, the healthcare team should present information in language that is easily understood by the patient, consistent with the patient’s level of education, and free of medical jargon.
  • Sufficient time should be taken to fully educate the patient about the goals of treatment and the need for adherence, both before beginning treatment and frequently during therapy.
  • Literature should be provided and, if available, peer counselors should be enlisted to reinforce education efforts. Attention to language and use of culturally sensitive education materials are essential.
  • Adherence tools should be provided. Written schedules, pictures of medications, pillboxes, alarms, and pagers may help patients understand and remember medication schedules. The need for greater adherence support (e.g., support groups, home visits, day treatment programs) should be assessed.
  • Reviewing the viral load response to ART in graphic form with the patient assists in reinforcing the efficacy of therapy.
  • The clinician should advise the patient regarding events that may interrupt treatment and interfere with patient access to medications (e.g., travel, pharmacy delays in restocking medications, manufacturer shortages, loss of medication, or incarceration). The patient should be counseled to notify his/her clinician for discussion of alternative options as soon as the patient foresees the occurrence of an interruption. Patients should be cautioned that if one (or more) drug in their ART regimen is not available for more than several days, all antiretroviral agents should be stopped until the entire ART regimen is again available to avoid the emergence of resistance while using a less suppressive regimen. This issue is of greatest concern when the antiretroviral agent in question is one to which a single point mutation confers a great degree of resistance (e.g., lamivudine and NNRTIs), which appears rapidly in the absence of a fully suppressive regimen.

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D. Patients’ Beliefs and Attitudes

When patients indicate that they do not believe that their medications will treat their infection, they are less likely to adhere to their regimens and need further preparation and guidance to successfully adhere to treatment.


  • If patients express beliefs that their medications work but also that diet, exercise, or prayer are particularly important in helping them fight their illness, then all of these modalities should be supported and integrated into the overall treatment plan, provided that they pose no harm to the patient.
  • Information about patients’ beliefs and attitudes should be communicated with all members of the healthcare team so that each provider can consistently address treatment issues within the context of the overall treatment plan.

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E. Substance Use and Adherence


  • Clinicians should help active substance users plan to decrease or stabilize their use in preparation for initiating ART.
  • The healthcare team should discuss with their patients how patterns of substance use may affect adherence and should work with other providers who possess experience with treating this group to encourage reduction in substance use. The link between reducing drug use and engaging in successful HIV treatment should be encouraged.

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F. How the Regimen Affects Adherence

Studies demonstrate the difficulty of maintaining strict adherence to complex ART regimens and show significant levels of poor adherence in the “real world” of HIV care. The largest obstacle in achieving strict adherence is the dosing schedule. There is a significant difference in adherence between regimens that are truly BID compared with TID or QID. Improved pharmacokinetics has produced ART regimens that simplify dosing; however, it is still important that clinicians devote sufficient time at each patient visit to assess the degree of adherence to prescribed therapies. Concern about potential side effects prompts some patients to diminish adherence, often without confiding in the healthcare team.

In November 2011, New York State adopted customized patient medication packaging, sometimes referred to as “comingling” of medications, which is a process whereby several different drugs are packaged together to be taken at the same time.60 Customized patient medication packaging has been shown to increase adherence to complex therapeutic regimens such as those required for patients with HIV/AIDS.60 In addition, customized patient medication packaging, simplifies dosing and may reduce reliance on daily “pill-minders” that patients often package themselves, which has a potential for error that would be avoided with use of customized patient packaging.


  • The entire medication list should be reviewed at every clinical visit to limit the concomitant use of unnecessary, ineffective, or contraindicated medications.
  • Patients should be educated about the risks and benefits of ART and preservation of future treatment options to allow them to develop realistic long-term expectations.
  • The side effects and toxicities associated with ART should be anticipated and explained. The patient should be informed that many side effects abate after the first weeks of treatment. Efforts should be made to plan for and to manage side effects at times when a new drug or regimen is being started.
  • The regimen should be simplified to the furthest extent possible. Attention should be paid to the pill count, frequency of dosing, meal requirements, potential side effects, and drug interactions when planning a regimen.
  • The regimen should be individualized. Each regimen should be planned on the basis of a given patient’s unique circumstances (e.g., difficulty swallowing pills; complex work schedule; irregular meals; need for privacy; preexisting symptoms, such as diarrhea, neuropathy, depression).

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May 2015

This section is currently under revision. Please refer to the DHHS guideline What to Start: Initial Combination Regimens for the Antiretroviral-Naive Patient. for the most current information on preferred initial ART regimens, alternative initial ART regimens, considerations for prescribing initial ART in the setting of specific clinical scenarios, and advantages and disadvantages of antiretroviral components recommended as initial ART.

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Periodic laboratory tests are necessary to evaluate the response to ART and its potential related side effects. In the setting of ART failure, viral resistance assays should be used.

A. Virologic and Immunologic Monitoring

Updated June 2015

Important Notes:

    • Quarterly CD4 count monitoring is no longer recommended for non-pregnant patients receiving ART who have consistently undetectable HIV RNA levels and CD4 counts >200 cells/mm3 (see Table 5 for recommended intervals). (AII)


  • Regular monitoring of HIV RNA levels remains the most accurate and meaningful measure of effective ART (see Table 5 for recommended intervals). (AI)


Clinicians should monitor HIV RNA levels and CD4 counts according to the recommended intervals in Table 5. Follow-up visits should be scheduled more frequently as clinically necessary to address non-HIV-related conditions, secondary prevention, and issues that may affect adherence to ART or retention in care, such as substance use, mental health disorders, unstable housing, or need for supportive services. (AIII)

Regular monitoring of CD4 counts in patients with consistently undetectable HIV viral loads and CD4 counts >200 cells/mm3 offers little utility in clinical practice today. Clinicians rarely use this information to guide decision-making for clinically stable, virologically suppressed patients. Monitoring of HIV RNA levels to confirm appropriate response to treatment and durable viral suppression is the most accurate and meaningful measure of the effectiveness of ART.61

Very few studies address the appropriate frequency of viral load monitoring. A recent retrospective study noted that the strongest predictor of virologic failure at 12 months was a missed or cancelled appointment rather than the interval of follow-up.62 However, this and other similar studies63,64 have significant limitations, including their retrospective nature and short follow-up periods. Until more definitive data are available, the decision to lengthen monitoring intervals for HIV RNA level should be individualized. Patients who are monitored at longer intervals should be carefully selected based on length of viral suppression, CD4 count, and adherence to medical care, including visit attendance and retention in care.

Key Point:
Quarterly HIV RNA monitoring remains appropriate for patients with a recent history of non-adherence, mental health disorders, substance use, homelessness, poor social support system, or other major medical conditions. Semiannual monitoring may be appropriate for patients with persistently undetectable HIV RNA and none of the above characteristics.


Table 5 provides a guide for monitoring HIV RNA levels and CD4 counts.

Table 5: Virologic and Immunologic Monitoring for Non-Pregnant Patientsa
HIV RNA Levels (copies/mL) CD4 Lymphocyte Count (cells/mm3)
• All patients Yes (AI) Yes (AI)
Treatment Monitoring
• Following (1) initiation of ART or (2) a change in ART regimen after virologic failureb with new resistance to prior ART • Within 4 weeks of initiation of ART or change in regimen (AIII)
• At least every 8 weeks until complete suppressionc is documented (AIII)
• Repeat at 12 weeks and then every 4 months until CD4 >200 cells/mm3 on two measurements obtained at least 4 months apart (AII); then monitor as below once suppressed
• Following a change in ART to simplify treatment regimen or reduce toxicity for patients with suppressed virus • Within 4 weeks after change in regimen to ensure continued suppression (AIII); then monitor as below for suppressed • Monitor as below for suppressed
• Patients on ART who achieve complete suppressionc • At least every 4 months after complete suppression (AIII)
• May extend intervals to every 6 months in selected stable patients with CD4 counts >200 cells/mm3 after 1 year of complete suppression62 (BII)
• If CD4 ≤300 cells/mm3: At least every 6 months (BIII)
• If CD4 >300 to ≤500 cells/mm3: At least every 12 months (BII)
• If CD4 >500 cells/mm3: further monitoring is optional (BIII)
• Patients on previously suppressive ART with new HIV RNAd above the lower limit of detection using a highly sensitive assayc All patients:
• Assess adherence (AIII)
• Assess for drug-drug interactions (AIII)

Viral load ≥500 copies/mL:
Have patient return within 2 weeks and:
• Repeat viral load (AII) and obtain resistance testing (AI)
• Obtain CD4 count if not done within previous 6 months (BIII)

Viral load <500 copies/mL:
Repeat viral load test within 4 weeks to differentiate low level transient viremia (“blip”) from virologic failure.b,e (AII)
If viral load remains detectable on repeat test:
• Obtain CD4 count if not done within previous 6 months (BIII)
• Consider resistance testingf (BIII)

Patients Not on ART
According to NYSDOH recommendations, ART is recommended for all HIV-infected patientsg
• If CD4 ≤500 cells/mm3: At least every 4 months (AIII)
• If CD4 >500 cells/mm3: At least every 6 months (AIII)
• Continue to discuss ART initiation (AI)
• If CD4 ≤500 cells/mm3:
At least every 4 months (AIII)
• If CD4 >500 cells/mm3:
At least every 6 months (AIII)
• Continue to discuss ART initiation (AI)
a For monitoring HIV RNA levels and CD4 counts in HIV-infected pregnant women, see the DHHS Recommendations for the Use of Antiretroviral Drugs in Pregnant HIV-1-Infected Women for Maternal Health and Interventions to Reduce Perinatal HIV Transmission in the United States.
b Virologic failure is defined as the inability to achieve or maintain suppression of viral replication to an HIV RNA level <200 copies/mL.65
c Complete suppression is generally considered below the lower limit of detection of a highly sensitive assay (<20 to <50 copies/mL).
d Patients with repeated intermittent low level viremia ≤200 copies/mL over a period of years without demonstrated failure may continue routine testing intervals.
e ART should not be changed based on a single viral load elevation. The risk of virologic rebound (breakthrough) increases when values are >500 copies/mL.66
f Standard genotypic tests may not provide resistance results when viral load is low. For repeated low-level viremia, an assay that detects resistance mutations in archived proviral DNA is available; however, clinical data are insufficient to recommend for or against its use in the patient care setting.
g See Section III: When to Initiate ART.

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Plasma HIV-1 RNA Level (Viral Load)
Plasma levels of viral RNA have been shown to correlate with clinical outcome, including overall mortality, and measurement of HIV RNA levels provides the most precise means of establishing whether a response to ART has occurred.67-71 HIV RNA levels should be obtained from all patients at baseline.72-77

For patients beginning ART, or those changing therapy as a result of virologic failure, HIV RNA should be measured at 4 weeks after initiation of therapy and should decrease by at least 1 log (10-fold) in the presence of effective therapy78 (see Table 6). For patients who do not have background antiretroviral resistance, an undetectable viral load (100,000 copies/mL can be expected to achieve an undetectable viral load within 6 months of effective treatment. Patients on previously suppressive ART with newly detectable HIV RNA levels may be experiencing low-level transient viremia (“blip”) and not virologic failure. Such patients with repeated intermittent low-level viremia ≤200 copies/mL over a period of years without demonstrated failure may continue routine testing intervals. An absent or incomplete response of viral load to ART should raise concerns about poor adherence to therapy and/or viral resistance79,80 (see Section IV: The Importance of Patient Adherence and Section VIII: Failure to Achieve Goals of Initial ART). ART should not be changed based on a single viral load elevation; however, repeated low-level viremia should prompt reassessment of the ART regimen and the need to adjust it. The risk of virologic rebound (breakthrough) increases when values are >500 copies/mL.66

Key Point:
Achieving and maintaining an undetectable viral load is always the goal of ART (see Appendix D and Appendix E).


Lymphocyte Subsets (CD4 Cell Count)
CD4 lymphocyte count is used to evaluate immunologic staging, predict the risk of clinical progression, and make decisions regarding prophylaxis of opportunistic infections (see Opportunistic Infection Prophylaxis). Historically, CD4 cell count has been used to establish a threshold for initiating ART. However, current guidelines in New York State recommend that all HIV-infected patients be evaluated for ART, regardless of CD4 cell count. For patients who may not be ready to initiate ART, CD4 cell count can be used to guide discussions between patient and provider regarding the urgency of initiating ART, as well as guide decisions to prescribe prophylaxis for opportunistic infections.81,82

Although CD4 counts should be obtained from patients at baseline,83-87 clinicians are unlikely to use CD4 counts to guide clinical decision-making in practice for virologically suppressed patients once their CD4 count remains above 200 cells/mm3. However, for persons infected with HIV-2 or HIV-1 variants that cannot be accurately quantified using viral load assays, CD4 count remains the most effective monitoring tool for progression of disease. See Human Immunodeficiency Virus Type-2.

Although a significant CD4 count increase often occurs among patients treated with effective ART, the absence of such an increase should not be interpreted as treatment failure if the viral load declines appropriately. ART regimens are generally not changed in patients with undetectable viral loads who experience immunologic failure, although patients should remain on appropriate prophylaxis for opportunistic infections based on CD4 count. See Opportunistic Infection Prophylaxis. Lack of correlation between viral load and CD4 cell response is particularly common among patients ≥50 years old88,89 and patients with low initial CD4 cell counts (3).83,90,91

Table 6: Interpretation of Viral Load
HIV-1 RNA Copy Number
Reduction With Antiretroviral Therapy if Patient Has 100,000 copies/mm3
Log Change Percent Decrease Fold Reduction Resultant Copy Number
0.5 66.00 3 33,000
1.0 90.00 10 10,000
2.0 99.00 100 1,000
3.0 99.90 1000 100

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B. HIV Resistance Assays

Updated October 2006


Clinicians should perform resistance testing under the following circumstances:

  • At baseline, regardless of whether ART is being initiated (genotypic testing)
  • In ART-naïve patients before initiation of ART (genotypic testing) (III)
  • In patients experiencing treatment failure or incomplete viral suppression while receiving ART (genotypic and/or phenotypic testing) (I)

When resistance testing is indicated, it optimally should be performed while patients are either receiving therapy or have been off therapy for less than 1 year. (III)

Clinicians should consult with an expert to interpret the results of resistance assays because the results of resistance assays are often complex (see Clinical Education Initiative sites available for phone consultation). (I)

In vitro testing for resistance to antiretroviral agents is an essential means of rationally directing therapy in treatment-experienced patients with virologic failure. Several cohort studies have demonstrated that up to 10% of recently infected ART-naïve patients harbor drug-resistant HIV. A recently reported resistance survey completed in New York State used genotypic testing to examine the prevalence of drug resistance in treatment-naïve persons and treatment-experienced persons off therapy for ≥6 months. This study found several important findings. First, 8.8% of ART-naïve patients harbored significant drug-resistance mutations. Resistance mutations were seen in 4.8% of those infected prior to 1999 compared with 11% of those infected in 2000-2001. The second important finding was that 28.6% of patients off therapy for ≥6 months had significant drug-resistance mutations. The prevalence of drug-resistance mutations was greater in patients with more extensive antiretroviral experience. Based on this, genotypic resistance testing of all patients before the initiation of ART is recommended. However, current techniques of assessing resistance have limitations, and treatment failure has been documented in the absence of resistance. In many cases, such failure may be attributable to either poor patient adherence or inadequate drug levels. The role of resistance testing has been best established in treatment-experienced patients in whom viral resistance often correlates closely with subsequent response to ART (see Table 7). Currently available resistance assays have been tested and are considered reliable only for clade B strains of HIV-1.

Key Point:
Resistance testing more reliably indicates drugs that are not likely to be effective rather than identifying those drugs that may suppress viral replication.


Table 7: Recommendations for the Use of Drug Resistance Assays
Clinical Setting/Recommendation Rationale
Prior to initiating treatment in ART-naïve patients, including in the setting of acute HIV infectionVirologic failure during ART

Suboptimal suppression of viral load after initiation of ARTa

Determine if drug-resistant virus was acquired so that an appropriate regimen may be chosen.Determine the role of resistance in drug failure, and maximize the number of active drugs in the new regimen.Determine the role of resistance, and maximize the number of active drugs in the new regimen if indicated.
Not generally recommended
More than 1 year after discontinuation of drugsPlasma viral load <500 to 1000 HIV RNA copies/mLb Drug-resistance mutations may become minority species in the absence of selective drug pressure and may not be detectable. Current assays may not detect minority drug-resistant species.Resistance assays cannot be reliably performed because of the low copy number of HIV RNA.
Adapted from the DHHS Guidelines for the Use of Antiretroviral Agents in HIV-Infected Adults and Adolescents (2006).
a In pregnant women initiating therapy, the clinician may not have as much time to monitor for suboptimal suppression.
b The cutoff will vary according to the manufacturer of the kit.


Third-party reimbursement programs provide reimbursement for three assays (either genotype or phenotype) per year (within 12 months following date of first use).

All resistance assays are limited because 1) they only detect the most prevalent viral populations (i.e., HIV strains that represent >20% of the total viral population); 2) they require that patients have a viral load of 500 to 1000 copies/mL or greater; and 3) testing yields best results when performed in patients receiving ART. Resistance testing performed in antiretroviral-experienced patients who are not receiving ART may not display all of the resistance mutations given lack of selective pressure; however, some mutations might persist for an indefinite period. Demonstration of resistance mutations known to confer decreased susceptibility by genotypic testing or evidence of reduced susceptibility by phenotypic testing should be considered accurate. The absence of resistance by either genotypic or phenotypic testing may indicate poor adherence in the setting of virologic failure; the absence of resistance should not be interpreted to mean that all viral populations in an individual patient are sensitive or lack resistance mutations.

A particularly important concept in the interpretation of drug-resistance assay results is that less prevalent (minority) resistant strains tend to decrease to below the threshold of detection, whereas sensitive (wild-type) virus emerges after a sustained period of treatment interruption. This occurrence may follow interruptions as short as 2 weeks or as long as 1 year. This may lead clinicians to incorrectly assume that drug-resistance mutations are not present. Neither genotypic nor phenotypic resistance testing will detect these less prevalent strains, which, nevertheless, may become dominant when selective pressure is again applied with the introduction of ART. Thus, interpretation of resistance becomes complicated in patients who have failed multiple antiretroviral regimens and/or who have the test(s) performed after ART has been discontinued. Because the rules for interpretation of results may change as understanding of resistance increases, clinicians should consult with an expert when interpreting complicated results. Current information on relevant mutations by antiretroviral class can be found on the IAS-USA website:

New resistance mutations and the emerging clinical significance of these mutations frequently change. Several resources are available for more information on drug resistance and resistance testing. These include:

The two types of resistance assays are described in the following sections. Each assay has advantages and disadvantages.

Genotypic Assays

Genotypic assays detect mutations in the genes of the reverse transcriptase and protease enzymes, as well as the gp41 domain for the currently available fusion inhibitors, that confer resistance to various antiretroviral drugs. The resistance mutation profile permits a prediction about the probability of resistance. Genotypic assays are less expensive, have a shorter reporting time (4-21 days) and have been more extensively studied. Disadvantages of the genotypic assays are that they may fail to identify important mutational changes that are not yet known to be associated with resistance, may be difficult to interpret, and may fail to detect interactions among mutations (e.g., M184V and zidovudine susceptibility).

One method of genotypic testing (“virtual phenotype type”) establishes a patient’s genotype and then predicts susceptibility by comparing a patient’s viral genotype to those in a large data set of viral isolates with correlated genotypic and phenotypic data. Viruses with similar genotypes to that of the patient’s virus are identified by searching the database, which then allows for the probable phenotype of the patient’s virus to be estimated. The advantages of this type of virtual phenotype testing are that the results are available quicker and the interpretation is similar to that of a conventional phenotype assay. A disadvantage is that the actual viral phenotype may be different as a result of limitations of the database.

For more information, refer to Diagnostic, Monitoring, and Resistance Laboratory Tests for HIV.

Phenotypic Assays

Phenotypic assays directly measure susceptibility of the patient’s HIV strain to specific individual drugs compared to sensitive HIV. The advantages of the phenotypic assays are that their results are easier to interpret than those of genotypic assays, they may also measure the effect of multiple mutations, and they may identify resistance as a result of mutations that may not yet be known. Disadvantages of phenotypic assays are that they are substantially more expensive, usually have a longer reporting time (21 to 28 days), and have thresholds for susceptibility that are undefined for some antiretroviral agents.

Of note, replicative capacity (RC) measurements may appear with the phenotypic testing results; however, there are no data regarding the utility of this measurement in therapeutic decision-making.

For more information, refer to Diagnostic, Monitoring, and Resistance Laboratory Tests for HIV.

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C. Laboratory Monitoring of ART Side Effects

This section describes monitoring of the following ART side effects: bone marrow suppression, pancreatitis, lactic acidosis/hepatic steatosis, hepatotoxicity, and renal toxicity. A table of common and/or severe adverse effects associated with ART is available in the Department of Health and Human Services guidelines, see Table 14: Antiretroviral Therapy-Associated Common and/or Severe Adverse Effects.

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Bone Marrow Suppression

Updated March 2006
Complete blood counts should be measured before initiation of ART therapy and at least every 4 months thereafter. For patients at high risk for bone marrow toxicity (e.g., those with advanced HIV infection, those with pre-treatment cytopenias, or those who are receiving zidovudine), blood counts may have to be monitored more frequently because significant cytopenias may occur. (III)

Bone marrow suppression is most often associated with zidovudine therapy. Significant drug-induced cytopenias become more common in the later stages of symptomatic HIV infection but occasionally develop abruptly in patients at earlier stages.

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Updated March 2006
When patients receiving ART present with signs or symptoms suggestive of pancreatitis, clinicians should obtain serum amylase and lipase levels. (III)

If signs or symptoms of pancreatitis occur in patients taking antiretroviral medications, the clinician should temporarily suspend the entire ART regimen. A new ART regimen may be initiated when enzymes are normalized but should not include antiretroviral medications that are most likely linked to pancreatitis, such as didanosine or stavudine.

An elevated serum amylase level should be confirmed with a serum lipase level. (III)

Clinicians should not prescribe didanosine for patients who have a history of pancreatitis. (III)

The incidence of pancreatitis is higher in patients infected with HIV and may be associated with opportunistic infections as well as ART. Didanosine has been the agent most often associated with this complication; however, cases of pancreatitis also have been reported with other antiretroviral agents since the advent of triple combination therapy. Tenofovir increases the levels of didanosine, thereby increasing the theoretical risk of pancreatitis. Thus, when these antiretroviral medications are used in combination, the dose of didanosine should be reduced (see Appendix A).

Pancreatitis should be considered in any patient receiving ART who presents with signs or symptoms of pancreatitis (e.g., abdominal pain, persistent nausea, and vomiting), and serum amylase and lipase should be obtained in this setting. Significant hypertriglyceridemia (>500 mg/dL) is associated with an increased risk of pancreatitis, particularly in patients with other risk factors for pancreatitis (e.g., alcohol or didanosine use). Other causes linked to pancreatitis in the general population should be included in the differential diagnosis.

Hyperamylasemia of non-pancreatic (e.g., parotid) origin may occur in HIV-infected patients. Serum lipase levels should be obtained to delineate the source of the increased amylase. Asymptomatic patients with modest elevations in amylase and lipase levels (<3-fold) may be monitored closely without change in therapy.

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Lactic Acidosis/Hepatic Steatosis

Updated March 2006


When patients develop symptoms consistent with lactic acidosis syndrome in conjunction with an elevated lactate level (>2 mmol/L) and decreased serum bicarbonate (<20 mmol/L), the clinician should temporarily discontinue the entire ART regimen while an evaluation is conducted. (II)

Routine monitoring of serum lactate levels is not indicated in asymptomatic patients. (I)

Patients who are asymptomatic and have an unexplained decrease in serum bicarbonate level (<20 mmol/L) should be promptly re-evaluated with a repeat test and a venous or arterial lactate. (II) If a venous lactate is mildly elevated (2.1 to 5.0 mmol/L), an arterial lactate should be obtained, and re-assessment for the presence of symptoms associated with lactic acidosis should be performed. (I) If the lactate is persistently elevated, the arterial pH is abnormal, or the patient has become symptomatic, ART should be discontinued. (III)

The syndrome of lactic acidosis/hepatic steatosis is rare but associated with a high mortality rate and has been most often associated with the use of NRTIs. Groups at higher risk for this complication include African Americans, obese patients, female patients, and patients with chronic hepatitis C virus (HCV). The syndrome is marked by constitutional complaints, such as abdominal pain, anorexia, nausea/vomiting, hyperventilation, and/or myalgias associated with elevations in serum lactate levels and decreased serum bicarbonate levels. Blood sampling for venous lactate levels should avoid the use of prolonged tourniquetting, and samples should be transported on ice and processed promptly. Lactic acidosis is believed to manifest only at lactate levels >5 mmol/L with an accompanying decreased bicarbonate level.

Patients taking NRTIs who present with constitutional symptoms should be evaluated for lactic acidosis, including lactate (arterial or venous) and bicarbonate level, arterial blood gas determination, serum amylase and lipase, and serum liver enzymes. In conjunction with the evaluation, ART should be discontinued. If the evaluation does not support the diagnosis of lactic acidosis, ART may be restarted.

Patients with mildly elevated lactate levels (2.1 to 5.0 mmol/L) and a normal bicarbonate level are usually asymptomatic. The clinical significance of mildly elevated lactate levels is still unknown. In the absence of decreased bicarbonate levels, lactic acidosis is uncommon.

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Updated January 2007
Clinicians should obtain serum liver enzyme levels at baseline and every 3 to 4 months thereafter in patients receiving ART. (III)

Clinicians should screen for alcohol use in patients with abnormal serum liver enzyme levels. (III)

Use of Nevirapine
Clinicians should not use nevirapine as part of the initial regimen in women with CD4 counts >250 cells/mm3 or men with CD4 counts >400 cells/mm3 because of an increased incidence of hepatotoxicity. (I)

When initiating an ART regimen that includes nevirapine, clinicians should obtain serum liver enzymes at baseline, at the time of dose escalation (14 days), and 2 weeks after dose escalation. (III)

Clinicians should counsel patients to seek medical evaluation when signs and symptoms of hepatitis, severe skin reactions, or hypersensitivity reactions related to nevirapine occur. Serum liver enzymes should be obtained whenever patients develop a rash during nevirapine therapy, particularly during the first 18 weeks of therapy. (II)

In the setting of hepatotoxicity related to nevirapine, patients should not be re-challenged with nevirapine. (I)

All antiretroviral agents have the potential to cause abnormalities in liver function, especially in patients with preexisting liver disease. Serum liver enzyme levels should be obtained at baseline and every 3 to 4 months in patients receiving ART. More frequent monitoring may be necessary for patients with preexisting liver disease or serum liver enzyme abnormalities. The use of full-dose ritonavir (600 mg twice daily) has been associated with worsening transaminases in patients with preexisting liver disease and should be avoided. Patients who develop serum liver enzyme abnormalities greater than five times the upper limit of normal should be promptly assessed. Any potentially hepatotoxic medication, including all antiretroviral agents, should be discontinued (see Section X: Management of Treatment Interruption).

A higher incidence of significant hepatotoxicity associated with nevirapine therapy has recently been reported, especially in women with CD4 counts >250 cells/mm3, men with CD4 counts >400 cells/mm3, and in the setting of HCV coinfection. The greatest risk of severe and potentially fatal hepatotoxicity occurs in the first 6 weeks of treatment; however, the FDA and the manufacturer strongly recommend intensive monitoring during the first 18 weeks of nevirapine therapy, with discontinuation of the drug if moderate or severe abnormalities occur. In the absence of definitive clinical evidence, monitoring serum liver enzymes every 2 weeks for the first month of nevirapine therapy, then monthly for the first 12 weeks, and every 1 to 3 months thereafter is a reasonable approach, given the potential severity of adverse events. It is essential that the 14-day lead-in period be strictly followed (see Appendix A for guidance on step-up dosing for nevirapine). In some cases, the hepatic injury progresses even after discontinuation of nevirapine. In the setting of hepatotoxicity related to nevirapine, the patient should not be re-challenged with nevirapine.

Some clinicians would avoid using efavirenz after severe nevirapine-related hepatotoxicity (LFTs >5x ULN) with or without Grade 4 rash (Stevens-Johnson syndrome); however, there is no clear evidence to support an association between nevirapine-related hepatotoxicity and efavirenz-related hepatotoxicity.92 For mild to moderate nevirapine-related hepatotoxicity (LFTs >3-5 x ULN), switching to efavirenz after complete resolution of hepatotoxicity is an option if there are no other contraindications to efavirenz. Contraindications to efavirenz include known adverse reactions to efavirenz, first-trimester pregnancy, or strong likelihood of becoming pregnant.

For pregnant women with nevirapine-related hepatotoxicity, the clinician should switch the regimen to 2 NRTIs + PI. Efavirenz should only be considered after the first 8 weeks of pregnancy if there are no other options and the benefits outweigh the risks. For additional information, see the DHHS Recommendations for the Use of Antiretroviral Drugs in Pregnant HIV-1-Infected Women for Maternal Health and Interventions to Reduce Perinatal HIV Transmission in the United States.

In the setting of severe nevirapine-related hepatotoxicity, all antiretroviral agents and any other possible offending agents should be discontinued. The risk of severe hepatotoxicity outweighs the risk of possible emergence of resistance. See Section X: Management of Treatment Interruption.

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Renal Toxicity

Updated September 2012


For all HIV-infected patients receiving ART:
Clinicians should routinely assess kidney function in all HIV-infected patients. A renal assessment should include:

  • Glomerular filtration rate estimated from serum creatinine (baseline and at least every 6 months) (AII)
  • Blood urea nitrogen (baseline and at least every 6 months) (AIII)
  • Urinalysis (baseline and at least annually) (AIII)
  • For patients with diabetes and no known proteinuria: calculation of urine albumin-to-creatinine ratio to detect microalbuminuria (baseline and at least annually) (AI)

For patients receiving tenofovir:
For patients initiating a tenofovir-containing regimen, clinicians should calculate glomerular filtration rates at initiation of therapy, 1 month after initiation of therapy, and then at least every 4 months thereafter.

Clinicians should adjust tenofovir dosing when glomerular filtration rate approaches 50 mL/min or discontinue tenofovir according to clinical status. (AII)

For patients receiving indinavir:
Clinicians should counsel patients receiving indinavir to drink at least 48 ounces of fluid per day.

HIV infection has been associated with several renal complications that may lead to renal insufficiency or failure.93,94 Renal impairment necessitates dose adjustment or discontinuation of many antiretroviral agents (see Appendix A).

Clinicians should routinely obtain urinalysis and serum creatinine levels as well as calculate glomerular filtration rates (GFR) to assess renal function. When calculating GFR, the clinician should consistently use the same method. GFR can be calculated by using one of the following equations:

  1. Chronic Kidney Disease Epidemiology Consortium (CKD-EPI): Estimates GFR based on age, race, and serum creatinine. A CKD-EPI calculator can be found at
  2. Modification of diet in renal disease (MDRD): Estimates GFR based on age, sex, height, serum creatinine, serum albumin, and serum blood urea nitrogen (BUN). An MDRD calculator can be accessed at
  3. Cockroft-Gault: Calculates creatinine clearance based on serum creatinine, age, weight, and sex. A Cockroft-Gault calculator can be accessed at

Tenofovir is excreted by glomerular filtration and tubular secretion. Renal impairment has been reported in patients receiving tenofovir.94,95 The extent of this toxicity is unclear. Additional risk factors include low body weight, older age, use of boosted regimens, hypertension, diabetes, and use of other nephrotoxic drugs. Hypophosphatemia may be an early indicator of renal failure. Clinicians may want to use a lower threshold for dose adjustment in patients receiving tenofovir. Clinicians should discontinue tenofovir when patients present with symptoms suggestive of Fanconi syndrome, such as declining renal function with associated metabolic acidosis, hypophosphatemia, hypokalemia, glycosuria, and uricosuria. The decision to rechallenge with tenofovir should be made on a case-by-case basis.

Indinavir (especially when used with ritonavir) and agents used to prevent and/or treat opportunistic infections may cause hematuria, pyuria, or crystalluria. Patients receiving indinavir should be counseled to drink at least 48 ounces of fluid per day. Clinicians should consider urinalysis every 3 to 4 months for patients receiving indinavir-containing regimens.

For additional information regarding renal assessment and management of kidney disease in HIV-infected patients, see Kidney Disease in HIV-Infected Patients.

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D. Monitoring for Allergic Reactions Associated with ART

Updated June 2010


When patients receive any new antiretroviral drugs, clinicians should educate them about the possibility of ART-associated allergic reactions, including a hypersensitivity reaction, and the range of possible symptoms (see Table 8). (III)

Clinicians should discontinue offending drugs when there is a moderate to severe skin reaction, mucous membrane involvement, systemic toxicity, or fever. (I)

Clinicians should perform HLA-B*5701 testing before initiating abacavir-based therapy.

Clinicians should avoid re-challenging patients with a medication that has been associated with a hypersensitivity reaction, especially in the setting of abacavir reactions and severe NNRTI reactions. (I)

In patients who develop mild rash in response to nevirapine, clinicians should avoid escalating the nevirapine dose to twice daily until after the rash has resolved. For patients with moderate to severe cutaneous toxicity, nevirapine should be discontinued and should not be re-challenged. Use of an alternate NNRTI should be avoided. (III)

Table 8: Antiretroviral Drugs Typically Associated with Allergic Reactions
Antiretroviral Drug
(usual timing of symptoms)
Most Frequent Symptoms Action
(First 4-6 weeks after initiation)
Hypersensitivity reaction: Fever, headache, gastrointestinal symptoms, malaise, arthralgias, myalgias, and respiratory problems. Skin involvement, with rash and pruritus may be mild or absent. • Prompt discontinuation of abacavir• Do not re-challenge
(First 4 weeks after initiation)
Mild to moderate cutaneous allergy • Consider systemic antihistamines while continuing delavirdine for mild rashes• Discontinue when there is a moderate to severe skin reaction, mucous membrane involvement, systemic toxicity, or fever
(First 4 weeks after initiation)
Mild to moderate cutaneous allergy • Consider systemic antihistamines while continuing efavirenz for mild rashes• Discontinue when there is a moderate to severe skin reaction, mucous membrane involvement, systemic toxicity, or fever
Enfuvirtide In the phase 3 trials of enfuvirtide, three cases of probable hypersensitivity were identified. These included, either individually or in combination, rash, fever, nausea and vomiting, chills, rigors, hypotension, and elevated LFTs.
(generally occurs in the 2nd week of treatment and is infrequent after week 4)
Severe reaction:cutaneous reaction involving the mucocutaneous surfaces (Stevens-Johnson syndrome, toxic epidermal necrolysis, and erythema multiforme)Mild reaction: mild skin rash Severe reaction:
▪ Discontinue etravirine promptly
Discontinue if rash accompanied by fever, hepatitis, and other systemic symptoms.
▪ Obtain serum liver enzyme levelsGrade 3 and 4 rashes reported in 1.3% of patientsRash more common in womenMild reaction:
▪ Manage with antihistamines and close monitoring
Fosamprenavir, tipranavir, and darunavir Mild to moderate cutaneous allergy • Patients with sulfa allergy may be at increased risk of developing an allergic reaction• For mild rashes, consider using systemic antihistamines while continuing protease inhibitors with sulfa moiety• Discontinue when there is a moderate to severe skin reaction, mucous membrane involvement, systemic toxicity, or fever
(First 2 to 18 weeks after initiation)
Severe reaction: cutaneous reaction involving the mucocutaneous surfaces (Stevens-Johnson syndrome), often accompanied by fever and severe hepatitisMild reaction: mild skin rash Severe reaction:
▪ Discontinue nevirapine promptly
▪ Obtain serum liver enzyme levels
▪ Do not re-challenge
▪ Do not use alternate NNRTI (however, patients with NNRTI rash did not have a higher incidence of rash when given etravirine)Mild reaction:
▪ Close monitoring recommended, but most clinicians would switch to an alternative antiretroviral
▪ Obtain serum liver enzyme levels
▪ Do not escalate dose to twice daily until the rash has resolved
Raltegravir Rashes, including severe skin rashes and cases of Stevens-Johnson syndrome and toxic epidermal necrolysis, have been reported • Discontinue if rash is accompanied by constitutional symptoms (i.e., fever, general malaise, fatigue, muscle or joint aches, blisters, oral lesions, conjunctivitis, facial edema, hepatitis, eosinophilia, angioedema)
* HLA-B*5701 is a pharmacogenetic test (HLA-B*5701) used to identify patients who are predisposed to abacavir hypersensitivity. Clinicians should perform HLA-B*5701 testing before initiating abacavir-based therapy.


Many medications pose the risk of causing various types of allergic reactions, typically presenting as maculopapular rash, with or without fever. Occasionally, a more severe hypersensitivity reaction occurs, consisting of rash and fever, with a combination of other symptoms, such as headache, arthralgias, hepatitis, eosinophilia, and GI or respiratory symptoms. The hypersensitivity reaction usually occurs within 2 to 6 weeks after the drug is started.

Although trimethoprim/sulfamethoxazole is the drug most frequently implicated in common allergic reactions in HIV-infected patients, abacavir, darunavir, tipranavir, fosamprenavir, all of the NNRTIs (nevirapine, delavirdine, efavirenz, etravirine), and enfuvirtide (less commonly) have been associated with a hypersensitivity reaction or syndrome (see Table 8). These reactions are for the most part idiosyncratic and unanticipated. The reactions to darunavir, fosamprenavir, tipranavir (all have a sulfa moiety), delavirdine, and efavirenz are generally mild to moderate cutaneous allergy (drug rash). Patients may rarely develop severe mucous membrane involvement with systemic toxicity. Occasionally, patients will only have a fever. Clinicians should discuss the possibility of these reactions with patients initiating ART because they are most commonly seen in the first 4 weeks of treatment; clinicians should educate patients about the symptoms of hypersensitivity.

Systemic antihistamines may be useful in treating mild cases while patients continue to receive the offending drug. The offending drug should be discontinued when there is a moderate to severe skin reaction, mucous membrane involvement, systemic toxicity, or fever.

Hypersensitivity to abacavir occurred in as many as 5% of patients before routine HLA-B*5701 testing was recommended. The reaction usually occurs within the first 10 to 14 days of therapy and rarely occurs after the first 6 weeks. Fever, headache, GI symptoms, malaise, arthralgias, myalgias, and respiratory problems are the most frequent manifestations of the abacavir hypersensitivity reaction. Skin involvement, with rash and pruritus, may be mild or absent. HLA-B*5701 is a pharmacogenetic test (HLA-B*5701) used to identify patients who are predisposed to abacavir hypersensitivity. Clinicians should perform HLA-B*5701 testing before initiating abacavir-based therapy.

Prompt discontinuation of abacavir when a hypersensitivity reaction is suspected is necessary because symptoms will worsen over time. Once abacavir has been discontinued because of a possible or definite hypersensitivity reaction, abacavir should never be administered again. Re-challenge may result in an anaphylactic reaction with associated hypotension or death.

Nevirapine, an NNRTI, has been associated with severe hypersensitivity reactions in the first 2 to 12 weeks of use. Graduated dosing of nevirapine at initiation with 200 mg daily for the first 2 weeks followed by 200 mg twice daily thereafter has reduced the incidence of hypersensitivity reactions. Systemic antihistamines or corticosteroids given at the time of nevirapine initiation have not been proven useful. Such reactions manifest as severe cutaneous reaction involving the mucocutaneous surfaces (Stevens-Johnson syndrome), often with accompanying fever and severe hepatitis. Deaths associated with these reactions have been reported. Patients who develop mild rashes without systemic toxicity may be managed with antihistamines and close monitoring. The nevirapine dose should not be escalated to twice daily until the rash has resolved. However, those with moderate to severe cutaneous toxicity should discontinue nevirapine promptly and should not be re-challenged with this drug. Because of potential cross-reactivity, use of an alternate NNRTI should be avoided in patients who have a severe reaction to nevirapine; however, the incidence of etravirine rash is not high in patients with a history of NNRTI rash.

Etravirine, an NNRTI, has been associated with hypersensitivity reaction. Up to 10% of patients in clinical trials reported rashes. Most reported mild to moderate rashes. Grade 3 and 4 rashes reported in 1.3% of patients, and up to 2.2% of patients required etravirine discontinuation. Rashes generally occur in the second week of treatment and are infrequent after week 4. Etravirine should be discontinued for severe rash or if rash is accompanied by fever, hepatitis, and other systemic symptoms.

In the phase 3 trials of enfuvirtide, three cases of probable hypersensitivity to the drug were identified. These have included, either individually or in combination, rash, fever, nausea and vomiting, chills, rigors, hypotension, and elevated serum liver enzymes.

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Updated March 2006


Clinicians should change a successful initial ART regimen when the patient’s adherence will be compromised by continuing the current regimen. (III)

When considering a change in the ART regimen due to drug toxicity, the clinician should confirm that the viral load is maximally suppressed. (III) If maximal viral suppression has been achieved, the clinician should substitute the offending drug. (I)

The clinician should review results from previous resistance testing before changing a successful regimen. (III)

Even when the goals of ART are achieved in a patient, clinicians may be faced with the challenge of making a change to a successful regimen. The reasons most often encountered are drug toxicity, quality-of-life issues, and/or fear of long-term adverse drug reactions. Changing therapy for quality-of-life issues or for fear of potential toxicity is appropriate if the patient’s concerns will lead to reduction in adherence or discontinuation of therapy. Many patients adhere less successfully to their ART regimen if they associate side effects with one or more of the drug components. It is important to fully discuss the issues of drug toxicity with the patient so that his/her expectations remain realistic.

Many side effects will abate after the first weeks of treatment. For patients who experience persistent mild to moderate side effects that cannot be managed and that would be expected to improve by a change in the ART regimen, it is good practice to consider changing the regimen when there are viable options. Following are examples of side effects that may be resolved by substituting the offending drug:

  • Peripheral neuropathy from stavudine or didanosine
  • Gastrointestinal intolerance from PIs
  • Insomnia, neuro-irritability, headaches, abnormal dreams from efavirenz or zidovudine
  • Changes in the skin/appendages (recurrent paronychia, xerosis, pruritus, jaundice) from indinavir, atazanavir, or zidovudine, emtricitabine (discoloration of palms/soles)
  • Renal lithiasis, renal colic from indinavir
  • Lipoatrophy or fat redistribution syndrome
  • Dyslipidemia, glucose intolerance from PIs
  • Rash from NNRTIs
  • Hypersensitivity from abacavir or nevirapine
  • Hepatitis from nevirapine or PIs

If adherence is compromised and the offending agent can be identified with a reasonable degree of certainty, a substitution for that one agent is appropriate as long as the viral load is maximally suppressed. Before changing therapy, however, results from previous resistance testing should be reviewed to identify drugs that are not likely to be effective.

In some situations, such as intractable diarrhea, one PI may be substituted for another. In other situations, a drug from one class may be replaced with a drug from another class. Studies have demonstrated that substituting an NNRTI for a PI in the setting of maximal suppression is generally safe and effective in the majority of patients. Although hypertriglyceridemia, hypercholesterolemia, or glucose intolerance would be expected to improve promptly by replacing a PI with an NNRTI, fat redistribution may change slowly after replacement of stavudine.

The risks of altering therapy are as follows:

  • The patient may experience toxicity with the new regimen
  • The exposure of HIV to multiple antiretroviral agents may increase the risk of drug resistance and reduce the number of available treatment options in the future
  • Maximal viral suppression may not be maintained
  • Changing regimens may have an emotional impact on the patient

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Updated March 2006, currently under revision


Clinicians should address adherence, obtain resistance assays, and consult with a provider with experience in HIV treatment before changing ART regimens that have failed.

Clinicians should not change an ART regimen when there is incomplete but significant viral suppression (≥0.5 log reduction, or 3-fold, from baseline viral load value) compared with baseline and a more effective ART regimen cannot be constructed as a result of drug resistance or intolerance.

The goal of ART is to use a regimen that is well tolerated and that will promote maximal viral suppression and immune reconstitution. Failure to demonstrate a >1.5-log drop in viral load within 3 months of treatment and, more importantly, failure to achieve a viral load <50 copies/mL within 6 months (depending on baseline viral load) indicates unsuccessful ART. The initial ART regimen affords the best opportunity to attain maximal viral suppression. Currently, in clinic practice, only 60% to 70% of patients receiving initial ART will achieve sustained viral loads below the limits of detection by ultrasensitive assays. The reasons for this are complex. Low levels of detectable viremia should not be the sole determinant of treatment failure.

Treatment failure is best defined by any one of the following:

  • Failure of viral load to decrease from baseline
  • Progressive increase in viral load after initial suppression
  • Progressive decline of CD4 cell counts
  • Progression of HIV disease

Failure of decline (1.5- to 2.5-log drop) in HIV RT-PCR levels 3 months after initiating ART is a poor prognostic sign and usually indicates that continuation of that particular regimen will fail. Possible reasons for failure are poor patient adherence, primary HIV resistance to the chosen drug regimen, pharmacokinetic issues, and drug-drug interactions. In such cases, it is advisable to obtain appropriate resistance testing to determine the best treatment options (see Section VI: Monitoring of Patients Receiving ART). Early discontinuation of the failing regimen is important to reduce the likelihood of the development of resistance mutations. A significant increase in viral load after an initial good response has a similar implication and should be handled in the same manner.

In contrast to the above situations, some patients will demonstrate a major reduction in HIV RT-PCR levels within several months of initiation of ART, but their viral loads will fail to become undetectable. Many of these patients will have had viral set points of >500,000 copies/mL prior to ART. In these cases, the nadir of viral load may not decrease to less than 5,000 to 10,000 copies/mL with the initial three-drug regimen. Over time, such patients have a higher risk of treatment failure because of the selection of resistance mutations. In these cases, some clinicians may enhance drug levels through the use of pharmacologic boosting (e.g., adding ritonavir) or may add a single agent for intensification. Although treatment intensification may produce good results in selected patients with relatively low viral loads, many clinicians view this as a suboptimal option or sequential monotherapy; therefore, the potential benefits of this strategy should be carefully weighed against the risk of introducing a single agent to a failing regimen that invariably would lead to resistance. A genotypic assay should be obtained to exclude the existence of primary drug resistance before intensifying the regimen.

Despite even maximal HIV suppression, CD4 cell counts may increase very slowly or not at all, especially for patients with baseline CD4 counts <100 cells/mm3 at the time of initiation of ART. Such patients have been shown to benefit from ART (i.e., reduction in likelihood of clinical disease progression), and therapy should not be altered. However, a small percentage of patients with excellent viral suppression will continue to demonstrate decreasing CD4 cell counts. This discordant response has been reported in a number of studies, although the mechanism is poorly understood. Some experts suggest empirically changing regimens in this setting.

Patients with drug-resistant HIV infection may maintain increased CD4 counts, most likely from the decreased replicative capacity of the resistant virus. Ideally, resistance testing should be obtained to determine if a new ART regimen can be constructed using available antiretroviral agents to attempt to achieve maximal viral suppression. However, when this is not possible, maintenance of the current regimen is acceptable.96

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Updated March 2006, currently under revision


Clinicians should consult with a provider with experience in HIV treatment when constructing a second-line regimen and salvage therapy regimens.

Clinicians should review individual antiretroviral history and results from HIV drug resistance testing when constructing salvage therapy regimens. Clinicians should consult with an expert to interpret the results of resistance assays. (I)

Clinicians should use a drug from a class that was not used in the first regimen when constructing a second-line regimen. (I)

When treating patients with high levels of HIV drug resistance, clinicians should consider using agents in novel antiretroviral classes or with unique resistance profiles, such as the entry inhibitors or drugs available through clinical trials or expanded access.

Although the best chance for success is with the initial ART regimen, the expectations are still good for second-line regimens, especially with the availability of new antiretroviral drugs. Salvage therapy refers to antiretroviral regimens prescribed for patients who have failed serial ART regimens. Use of the term “salvage therapy” originates from the clinical observation that fewer than 40% to 50% of patients will respond optimally to new ART regimens after first and second ART regimens have failed.

Because of cross-resistance within antiretroviral classes, the clinician cannot assume that the patient’s HIV strain(s) will be sensitive to a novel drug in the same class. Several studies examining the utility of HIV resistance testing in ART-experienced patients have shown that these tests are valuable when choosing subsequent successful ART regimens. However, when multiple regimens have failed in a patient, resistance testing is of limited value. In some cases, when multiple resistance mutations are found on genotypic resistance analysis, phenotypic resistance testing may be helpful in constructing an effective regimen. Expert interpretation of the resistance results in conjunction with a detailed antiretroviral history, including any previous resistance testing, is essential.

For a second-line regimen, drugs from a class that was not used in the first regimen should be used. Agents in new drug classes (e.g., an entry inhibitor) or with novel resistance profiles may lead to an improved antiviral response for patients with multi-drug resistant HIV. Clinical trials and “expanded access” therapies should be considered in this setting. Combinations of five or more antiretroviral drugs, colloquially referred to as “mega-ART” or “multi-drug rescue therapy,” may be attempted in patients who have a high level of drug resistance in all available antiretroviral classes. There are limited data on such an approach, with an unclear benefit in the context of the high pill burdens and significantly increased toxicity of such complex regimens.

When maximal suppression is not achievable due to inability to construct a fully effective regimen, partial viral suppression (<0.5 log or 3-fold reduction from baseline viral load value) and stable CD4 counts are reasonable alternative goals. When CD4 counts are decreased, prophylaxis for opportunistic infections should be initiated.

Several investigators have shown that individuals infected with HIV may become superinfected with a different strain of HIV in the setting of high-risk behavior. In some cases, superinfecting HIV strains may carry drug-resistance mutations. Therefore, sudden regimen failure in a patient who was virologically controlled should raise suspicion that HIV superinfection may be present. Resistance testing and safer-sex counseling are appropriate in these settings.

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Updated June 2006


Patients should be discouraged from stopping ART without first consulting with their clinician. (III)

When ART is interrupted, clinicians should inform patients of the potential increased risk of transmitting HIV. Risk-reduction counseling and prevention interventions should be intensified at this time.

Before interrupting ART in patients receiving antiretroviral medications with prolonged half-lives, such as NNRTIs, clinicians should consult with a provider with experience in HIV treatment for guidance on how to avoid the emergence of resistance.

Clinicians should not interrupt lamivudine, emtricitabine, or tenofovir (or combination pills containing these drugs) in patients who are co-infected with chronic hepatitis B without implementing another HBV treatment option.

Strategic treatment interruption (STI) is not recommended in the management of the HIV-infected patient. (I)

There are several reasons why it may be necessary to interrupt ART. Following are some scenarios that may result in an interruption in treatment:

  • Serious adverse drug reactions (e.g., rashes, neuropathy, severe lipoatrophy or fat redistribution, severe nephrolithiasis)
  • Lack of access to drugs due to poverty, incarceration, or lack of medical benefits
  • Medical/surgical conditions requiring patients to avoid eating or drinking for a specified time period (e.g., pancreatitis, appendicitis)
  • Poor adherence—in some cases, lack of adherence may be sufficient cause for the clinician to stop treatment while further interventions and education attempts are undertaken
  • Minor drug side effects that mimic disease progression, making it necessary to temporarily interrupt therapy for clinical evaluation of signs and symptoms
  • Patient choice—patients may decide to stop therapy due to treatment fatigue, fear of toxicities (e.g., fat redistribution, cardiac disease), traveling overseas for an extended period, perceived ineffectiveness of medications, or pregnancy and fear of teratogenicity.

Discontinuation of ART by patient’s choice is a complex issue regardless of whether viral suppression had been obtained with the regimen. In some instances, patients lack understanding of the benefits of the medications and fail to adhere to the prescribed regimen. The reasons for non-adherence are multiple (see Section IV: The Importance of Patient Adherence).

Treatment interruption, especially in established (>6 months) HIV infection, can be potentially dangerous. It could lead to dramatic increases in HIV viral load, which may exceed baseline viral load levels, and precipitous declines in CD4 cell counts, which may reach pre-treatment levels, with the risk of clinical events. The Strategies for Management of Antiretroviral Therapy (SMART) trial compared patients receiving continuous ART with patients who were given intermittent ART. The patients in the intermittent therapy group received ART whenever CD4 counts decreased to <250 cells/mm3 then discontinued treatment when CD4 counts increased again to >350 cells/mm3. Patients in the intermittent treatment group had more than twice the risk of progression to AIDS or death compared with the continuous therapy group.

During a treatment interruption, patients may present as if they have acute HIV syndrome or the initial HIV-related symptoms may return. Rebound in HIV-1 RNA plasma level may enhance horizontal and vertical transmission of HIV-1, which is of particular importance during pregnancy when a rebound in viral load may favor transplacental, peripartum, and breastfeeding-related transmission. CD4 cell counts may take longer to decrease after the discontinuation of ART; therefore, clinicians should inform patients that a stable CD4 count after discontinuation of therapy does not predict long-term immunologic stability.

Treatment interruption also may result in selection of resistance mutations. The increasing use of antiretroviral medications with prolonged half-lives and low resistance thresholds complicates discontinuation of treatment. Low plasma levels of antiretroviral medications with prolonged half-lives, such as nevirapine and efavirenz, can be detected many days after discontinuation of the medication. These low levels, although insufficient to suppress viral replication, may select for resistance mutations. Reports have documented the association between discontinuation of an NNRTI, lingering low plasma levels, and emergence of resistance mutations. The duration of these low detectable levels may vary widely from patient to patient. There is no consensus regarding how best to manage treatment discontinuation. Some experts would suggest replacing the NNRTI with a PI and continuing the two NRTIs and PI for approximately 1 week before interrupting therapy. Others would discontinue the NNRTI first and continue the NRTIs for several days (referred to as an “NRTI tail”). Resistant virus usually recedes and wild-type, susceptible virus predominates once treatment is interrupted; however, once antiretroviral medications are re-started, if resistance develops, selective pressure is again established and resistant virus again emerges. These complex considerations coupled with the rapid changes in knowledge and treatment regimens make it advisable to consult with a provider who has experience with management of ART when considering discontinuation of ART.

Structured or strategic treatment interruption is a theoretical approach aimed at reducing long-term toxicity and enhancing HIV-specific immune response while maintaining treatment options. To date, strategic treatment interruptions in patients receiving ART with an undetectable viral load have failed to consistently stimulate HIV-specific T-helper and cytotoxic T-lymphocyte responses. Ongoing clinical trials are trying to elucidate predictors of response. Several treatment interruption studies are basing re-initiation of treatment on CD4 threshold. Preliminary data from some of these trials indicate increased morbidity and mortality among patients in the treatment-interruption arm. At this time, structured treatment interruption cannot be recommended, and it should only be considered in the context of a clinical trial. To locate a clinical trial, refer to the AIDS Community Research Initiative of America clinical trials directory at:

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Updated March 2006


Referral of patients to research protocols should be 1) to provide treatment or diagnostic options that may be otherwise unavailable and that may enhance treatment outcome, and 2) to attempt to answer a relevant research question. (III)

Patients should be fully informed of any financial benefit their referral to a research study might have for the referring clinician. (III)

Patients should be informed that research studies often require major commitments of time and effort in addition to potential unforeseeable risk. (III)

The clinician should provide assistance to patients who want to participate in research studies. (III)

The first priority in the care of any patient is to maximize the therapeutic benefit of treatment and to support the individual. Sometimes patients ask if they can help with any new research studies, and clinicians often realize that the patient might benefit from a therapy that is currently under study. In addition, many standard therapies are still being scrutinized in terms of timing and appropriateness. Because there are so many clinical uncertainties (e.g., when to initiate ART, what is the optimal initial therapy, whether there are occasions for interruption of therapy), the clinician should keep in mind that if a patient is willing to join a trial that will help to resolve these issues, then ultimately there may be a benefit to many others.

In considering referral to a clinical study, the clinician should review with the patient the risks and benefits of participating:

  • If the agent is new, what toxicities have been shown in preliminary trials?
  • What is the patient’s current clinical status and what would be the risks of not using the new agent(s) (i.e., the natural history of the patient’s current condition)?
  • If the trial compares randomization to 1 of 2 standard therapies, are the current data insufficient to recommend one or the other to the patient?
  • If the clinical trial is being held in a center other than the institution where the patient is receiving primary care, how much time and travel will the trial involve? Will the patient get any help with time/travel issues?
  • Is the patient willing and able to meet the rigors that may be imposed on study participants?
  • Is there a stipend for participation?

If the clinician is also an investigator on the study, it is important that he/she is scrupulous in avoiding any real or perceived conflict of interest in the referral. The informed consent that the patient signs should disclose any financial benefit to the clinician if the patient enrolls. Clinicians should be sensitive to some communities’ continued distrust derived from a history of research that was tainted by racism or other prejudice, such as the Tuskegee study. Discussions about research studies should be culturally sensitive, and the voluntary nature of all enrollments must be made very clear.

Clinicians providing care to patients with HIV/AIDS have an obligation to keep abreast of trials that are available in their geographic area and in the field of HIV/AIDS in general. A resource that may help with this process is the AIDS Clinical Trials Information Service (phone: 1-800-TRIALS-A; website: Other resources are listed at AIDS Community Research Initiative of America ( Establishing a referral network with accessible study centers can be helpful. Centers involved in research should make an effort to be aware of HIV clinicians in their area and vice versa.

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2. Kitahata MM, Gange SJ, Abraham AG, et al. Effect of early versus deferred antiretroviral therapy for HIV on survival. N Engl J Med 2009;360:1897-1899. [PubMed] Initiating ART at CD4 counts <500 cells/mm3 and older age were independently associated with increased mortality.

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14. Garvey L, Surendrakumar V, Winston A. Low rates of neurocognitive impairment are observed in neuro-asymptomatic HIV-infected subjects on effective antiretroviral therapy. HIV Clin Trials 2011;12:333-338. [PubMed] Rates of neurocognitive impairment were low in patients receiving ART.

15. Winston A, Puls R, Kerr SJ, et al. Dynamics of cognitive change in HIV-infected individuals commencing three different initial antiretroviral regimens: A randomized, controlled study. HIV Med 2012;13:245-251. [PubMed] Neurocognitive function improves over the first year of initiating ART in neuro-asymptomatic patients.

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17. Silverberg MJ, Chun C, Leyden W, et al. HIV infection, immunodeficiency, viral replication, and the risk of cancer. Cancer Epidemiol Biomarkers Prev 2011;20:2551-2559. [PubMed] Immunodeficiency was positively associated with the following non-HIV-related malignancies: lung cancer, colorectal cancer, and melanoma compared with HIV-uninfected individuals. Earlier ART initiation to maintain high CD4 levels might reduce the risk of cancer.

18. Bruyand M, Thiébaut R, Lawson-Ayayi S, et al. Role of uncontrolled HIV RNA level and immunodeficiency in the occurrence of malignancy in HIV-infected patients during the combination antiretroviral therapy era: Agence Nationale de Recherche sur le Sida (ANRS) CO3 Aquitaine Cohort. Clin Infect Dis 2009;49:1109-1116. [PubMed] CD4 counts maintained at >500 cells/mm3 helps to prevent the occurrence of malignancy.

19. Guiget M, Boue F, Cadranel J, et al. Effect of immunodeficiency, HIV viral load, and antiretroviral therapy on the risk of individual malignancies (FHDH-ANRS CO4): A prospective cohort study. Lancet Oncol 2009;10:1152-1159. [PubMed] Risk for malignancies is decreased when CD4 counts are maintained above 500 cells/mm3.

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36. Uy J, Armon C, Buchacz K, et al. Initiation of HAART at higher CD4 cell counts is associated with a lower frequency of antiretroviral drug resistance mutations at virologic failure. J Acquir Immune Defic Syndr 2009;51:450-453. [PubMed] Patients failing ART who initiated at <350 cells/mm3 were more likely to develop resistance mutations than failing patients who initiated ART at CD4 counts >350 cells/mm3.

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39. Donnell D, Baeten JM, Kiarie J, et al. Heterosexual HIV-1 transmission after initiation of antiretroviral therapy: A prospective cohort analysis. Lancet 2010;375:2092-2098. [PubMed] Use of antiretroviral therapy was accompanied by a 92% reduction in HIV-1 transmission to the uninfected partner.

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53. Havlir DV, Kendall MA, Ive P, et al. Timing of antiretroviral therapy for HIV-1 infection and tuberculosis. N Engl J Med 2011;365:1482-1491. [PubMed]

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70. Mellors JW, Muñoz A, Giorgi JV, et al. Plasma viral load and CD4+ lymphocytes as prognostic markers of HIV-1 infection. Ann Intern Med 1997;126(12):946-54. [PubMed]

71. Thiébaut R, Morlat P, Jacqmin-Gadda H, et al. Clinical progression of HIV-1 infection according to the viral response during the first year of antiretroviral treatment. Groupe d’Epidémiologie du SIDA en Aquitaine (GECSA). AIDS 2000;14(8):971-8. [PubMed]

72. Tarwater PM, Gallant JE, Mellors JW, et al. Prognostic value of plasma HIV RNA among highly active antiretroviral therapy users. AIDS 2004;18(18):2419-23. [PubMed]

73. Gulick RM, Meibohm A, Havlir D, et al. Six-year follow-up of HIV-1-infected adults in a clinical trial of antiretroviral therapy with indinavir, zidovudine, and lamivudine. AIDS 2003;17(16):2345-9. [PubMed]

74. Wu H, Mellors J, Ruan P, et al. Viral dynamics and their relations to baseline factors and longer term virologic responses in treatment-naive HIV-1-infected patients receiving abacavir in combination with HIV-1 protease inhibitors. J Acquir Immune Defic Syndr 2003;33(5):557-63. [PubMed]

75. Porter DP, Kulkarni R, Fralich T, et al. 96-week resistance analyses of the STaR study: rilpivirine/emtricitabine/tenofovir DF versus efavirenz/emtricitabine/tenofovir DF in antiretroviral-naive, HIV-1-infected subjects. HIV Clin Trials 2015;16(1):30-8. [PubMed]

76. Behrens G, Rijnders B, Nelson M, et al. Rilpivirine versus efavirenz with emtricitabine/tenofovir disoproxil fumarate in treatment-naïve HIV-1-infected patients with HIV-1 RNA ≤100,000 copies/mL: week 96 pooled ECHO/THRIVE subanalysis. AIDS Patient Care STDS 2014;28(4):168-75. [PubMed]

77. Molina JM, Clumeck N, Redant K, et al. Rilpivirine vs. efavirenz in HIV-1 patients with baseline viral load 100,000 copies/ml or less: week 48 phase III analysis. AIDS 2013;27(6):889-97. [PubMed]

78. Haubrich RH, Riddler SA, Ribaudo H, et al. Initial viral decay to assess the relative antiretroviral potency of protease inhibitor-sparing, nonnucleoside reverse transcriptase inhibitor-sparing, and nucleoside reverse transcriptase inhibitor-sparing regimens for first-line therapy of HIV infection. AIDS 2011;25:2269-2278. [PubMed]

79. Townsend D, Troya J, Maida I, et al. First HAART in HIV-infected patients with high viral load: Value of HIV RNA levels at 12 weeks to predict virologic outcome. J Int Assoc Physicians AIDS Care (Chic) 2009;8:314-317. [PubMed]

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81. Lopez Bernaldo de Quiros JC, Miro JM, Peña JM, et al. A randomized trial of the discontinuation of primary and secondary prophylaxis against Pneumocystis carinii pneumonia after highly active antiretroviral therapy in patients with HIV infection. Grupo de Estudio del SIDA 04/98. N Engl J Med 2001;344(3):159-67. [PubMed]

82. El-Sadr WM, Burman WJ, Grant LB, et al. Discontinuation of prophylaxis for Mycobacterium avium complex disease in HIV-infected patients who have a response to antiretroviral therapy. Terry Beirn Community Programs for Clinical Research on AIDS. N Engl J Med 2000;342(15):1085-92. [PubMed]

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84. Oldfield EC 3rd, Fessel WJ, Dunne MW, et al. Once weekly azithromycin therapy for prevention of Mycobacterium avium complex infection in patients with AIDS: a randomized, double-blind, placebo-controlled multicenter trial. Clin Infect Dis 1998;26(3):611-9. [PubMed]

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86. Schneider MM, Hoepelman AI, Eeftinck Schattenkerk JK, et al. A controlled trial of aerosolized pentamidine or trimethoprim-sulfamethoxazole as primary prophylaxis against Pneumocystis carinii pneumonia in patients with human immunodeficiency virus infection. The Dutch AIDS Treatment Group. N Engl J Med 1992;327(26):1836-41. [PubMed]

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88. Gras L, Kesselring AM, Griffin JT, et al. CD4 cell counts of 800 cells/mm3 or greater after 7 years of highly active antiretroviral therapy are feasible in most patients starting with 350 cells/mm3 or greater. J Acquir Immune Defic Syndr 2007;45:183-192. [PubMed]

89. Sabin CA, Smith CJ, d’Arminio Monforte A, et al., Collaboration of Observational HIV Epidemiological Research Europe (COHERE) Study Group. Response to combination antiretroviral therapy: Variation by age. AIDS 2008;22:1463-1473. [PubMed]

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91. Garcia F, de Lazzari E, Plana M, et al. Long-term CD4+ T-cell response to highly active antiretroviral therapy according to baseline CD4+ T-cell count. J Acquir Immune Defic Syndr 2004;36:702-713.[PubMed]

92. Sulkowski MS, Thomas DL, Mehta SH, et al. Hepatotoxicity associated with nevirapine or efavirenz-containing antiretroviral therapy: Role of hepatitis C and B infections. Hepatology 2002;35;182-189. [PubMed] The greatest risk of NNRTI-associated severe hepatotoxicity was observed in patients taking NVP, those with hepatitis B or C co-infection, and those co-administered PIs.

93. Miro JM, Cofan F, Trullas JC, et al. Renal dysfunction in the setting of HIV/AIDS. Curr HIV/AIDS Rep 2012;9:187-199. [PubMed] HIV-infected individuals commonly experience renal complications and have a high prevalence of risk factors, including HIV infection itself, that contribute to the development of kidney disease.

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FDA-Approved HIV Medications (July 2015)

Drug Class and Name Acronym Brand Name
Class names link to class characteristics tables at; drug names link to each drug’s information page in the AIDSinfo Drug Database
Nucleoside Reverse Transcriptase Inhibitors (NRTIs)
Abacavir ABC Ziagen
Didanosine ddI Videx, Videx EC (enteric-coated)
Emtricitabine FTC Emtriva
Lamivudine 3TC Epivir
Stavudine d4T Zerit
Tenofovir Disoproxil Fumarate TDF Viread
Zidovudine AZT, ZDV Retrovir
Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs)
Delavirdine DLV Rescriptor
Efavirenz EFV Sustiva
Etravirine ETR Intelence
Nevirapine NVP Viramune,
Viramune XR (extended release)
Rilpivirine RPV Edurant
Protease Inhibitors
Atazanavir ATV Reyataz
Darunavir DRV Prezista
Fosamprenavir FPV Lexiva
Indinavir IDV Crixivan
Nelfinavir NFV Viracept
Ritonavir RTV Norvir
Saquinavir SQV Invirase
Tipranavir TPV Aptivus
Fusion Inhibitor
Enfuvirtide T-20 Fuzeon
CCR5 Co-receptor Antagonist
Maraviroc MVC Selzentry
Integrase Inhibitors (INSTIs)
Dolutegravir DTG Tivicay
Elvitegravir EVG Vitekta
Raltegravir RAL Isentress
Pharmacokinetic Enhancers
Cobicistat COBI Tybost
Abacavir/lamivudine ABC/3TC Epzicom
Abacavir/dolutegravir/lamivudine ABC/DTG/3TC Triumeq
Abacavir/lamivudine/zidovudine ABC/3TC/ZDV Trizivir
Atazanavir/cobicistat ATV/COBI Evotaz
Darunavir/cobicistat DRV/COBI Prezcobix
Efavirenz/emtricitabine/tenofovir disoproxil fumarate EFV/FTC/TDF Atripla
Elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide fumarate EVG/COBI/FTC/TAF Genvoya
Elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate EVG/COBI/FTC/TDF Stribild
Emtricitabine/rilpivirine/tenofovir alafenamide fumarate FTC/RPV/TAF Odefsey
Emtricitabine/rilpivirine/tenofovir disoproxil fumarate FTC/RPV/TDF Complera
Emtricitabine/tenofovir disoproxil fumarate FTC/TDF Truvada
Lamivudine/zidovudine 3TC/ZDV Combivir
Lopinavir/ritonavir LPV/r Kaletra
See also: NIAID Drugs That Fight HIV-1:


FDA Pregnancy Categories

A Adequate and well-controlled studies of pregnant women fail to demonstrate a risk to the fetus during the first trimester of pregnancy (and there is no evidence of risk during later trimesters).
B Animal reproduction studies fail to demonstrate a risk to the fetus and adequate and well-controlled studies of pregnant women have not been conducted.
C Safety in human pregnancy has not been determined, animal studies are either positive for fetal risk or have not been conducted, and the drug should not be used unless the potential benefit outweighs the potential risk to the fetus.
D Positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experiences, but the potential benefits from the use of the drug in pregnant women may be acceptable despite its potential risks.
X Studies in animals or reports of adverse reactions have indicated that the risk associated with the use of the drug for pregnant women clearly outweighs any possible benefit.


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Under Revision June 2015

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Table 1: Risk of Progression to AIDS-Defining Illness in a Cohort of Homosexual Men
Predicted By Baseline CD4 T Cell Count and Viral Loada
CD4 ≤200
Plasma Viral Load (copies/mL)
(AIDS-Defining Complication)
bDNA RT-PCR n 3 years 6 years 9 years
≤ 500 ≤ 1,500
501 – 3,000 1,501 – 7,000
3,001 – 10,000 7,001 – 20,000
10,001 – 30,000 20,001 – 55,000
> 30,000 > 55,000
CD4 201–350e
Plasma Viral Load (copies/mL)
(AIDS-Defining Complication)
bDNA RT-PCR n 3 years 6 years 9 years
≤ 500 ≤ 1,500
501 – 3,000 1,501 – 7,000
3,001 – 10,000 7,001 – 20,000
10,001 – 30,000 20,001 – 55,000
> 30,000 > 55,000
CD4 >350
Plasma Viral Load (copies/mL)
(AIDS-Defining Complication)
bDNA RT-PCR n 3 years 6 years 9 years
≤ 500 ≤ 1,500
501 – 3,000 1,501 – 7,000
3,001 – 10,000 7,001 – 20,000
10,001 – 30,000 20,001 – 55,000
> 30,000 > 55,000
Adapted from the DHHS Guidelines for the Use of Antiretroviral Agents in HIV-infected Adults and Adolescents (2006).
a Data from the Multi-Center AIDS Cohort Study (MACS).
b MACS numbers reflect plasma HIV RNA values obtained by version 2.0 bDNA testing. RT-PCR values are consistently 2- to 2.5-fold higher than bDNA values, as indicated. It should be noted that the current generation bDNA assay (3.0) gives similar HIV-1 RNA values as RT-PCR except at the lower end of the linear range (<1,500 copies/mL).
c In this study, AIDS was defined according to the 1987 CDC definition and does not include asymptomatic individuals with CD4 T cell counts <200 mm3.
d Too few subjects were in the category to provide a reliable estimate of AIDS risk.
e A recent evaluation of data from the MACS cohort of 231 individuals with CD4 T cell counts >200 and <350 cells/mm3 demonstrated that of 40 (17%) individuals with plasma HIV RNA <10,000 copies/mL, none progressed to AIDS by 3 years (Alvaro Munoz, personal communication). Of 28 individuals (29%) with plasma viremia of 10,000-20,000 copies/mL, 4% and 11% progressed to AIDS at 2 and 3 years, respectively. Plasma HIV RNA was calculated as RT-PCR values from measured bDNA values.

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Table 1: Prognosis According to CD4 Cell Count and Viral Load in the Pre-HAART and HAART Eras
Reprinted with permission from Elsevier (The Lancet, 2002, Vol 360, 19-29).

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