Pachamuthu Balakrishnan

Incidence of immune reconstitution syndrome in HIV/tuberculosis-coinfected patients after initiation of generic antiretroviral therapy in India.

This paper describes the incidence of immune reconstitution syndrome (IRS) from the developing world and implications for clinicians. Eleven of 144 HIVand tuberculosis (TB)-coinfected individuals followed for 72 person-years developed IRS within 6 months of initiating generic highly active antiretroviral therapy (HAART). All of the IRS patients were male, with a median age of 29 years; median CD4 at HAART initiation was 123 cells/mm3, and 6-month median CD4 rise was 124 cells/mm3. There was no statistical difference in CD4 rise or CD4 count and duration of TB treatment at HAART initiation between those who did and those who did not develop IRS (P = 0.8380). The median time to development of clinical IRS was 42 days (range 10-89 days). The incidence of IRS in this cohort is 15.2 cases per 100 patient-years. With increased coprevalence of opportunistic infections, especially TB, and increasing access to antiretroviral therapy in the developing world, clinicians in these countries must be able to identify IRS and relieve symptoms without compromising clinical care.

Reasons for modification of generic highly active antiretroviral therapeutic regimens among patients in southern India.

Objective:To describe reasons for modification and discontinuation of antiretroviral regimens in association with adverse events (AEs), treatment failure, and cost among patients in southern India. Methods:Secular trends of patients initiating highly active antiretroviral therapy (HAART) between January 1996 and October 2004 at a tertiary HIV referral center in India were analyzed using a previously validated natural history database. Results:All previously antiretroviral therapy-naive patients who initiated HAART (N = 1443) and had at least 1 follow-up visit were evaluated. The median CD4 count at the time of initiating HAART was 108 cells/μL The most common first-line regimens were stavudine (d4T) plus lamivudine (3TC) plus nevirapine (NVP) (63%), zidovudine (AZT) plus 3TC plus NVP (19%), d4T plus 3TC plus efavirenz (EFV) (9%), and AZT plus 3TC plus EFV (4%). Twenty percent of patients modified their first-line regimen. The most common reason for modifying therapy was the development of an AE (64%), followed by cost (19%) and treatment failure (14%), with median times to modify therapy being 40, 151, and 406 days, respectively. Common AEs were itching and/or skin rash (66%), hepatotoxicity (27%), and anemia (23%). Nine percent of patients discontinued therapy entirely after a median duration of 124 days, primarily because of cost (64%). Conclusion:The most common reason for modifying therapy was the occurrence of AEs, whereas cost was the most common reason for discontinuing therapy. Despite increasing access to lower cost generic HAART in India, even less expensive and more tolerable first-line regimens and cost-effective treatment monitoring tools need to be introduced to achieve better treatment outcomes and access in resource-constrained settings.

The safety, tolerability and effectiveness of generic antiretroviral drug regimens for HIV-infected patients in south India.

We investigated the safety, tolerability and effectiveness of locally produced generic highly active antiretroviral therapy (HAART) regimens with a chart review conducted at YRG CARE, a tertiary HIV referral centre in India. A total of 333 patients had been on Indian-manufactured generic HAART for at least 3 months. In this cohort, generic HAART was safe, well tolerated and effective at increasing CD4 T-lymphocyte counts in patients with advanced HIV, comparable to the experience with proprietary HAART.

High Frequency of Clinically Significant Mutations after First-Line Generic Highly Active Antiretroviral Therapy Failure: Implications for Second-Line Options in Resource-Limited Settings

Continuation of failed highly active antiretroviral therapy regimens can lead to the accumulation of mutations that may limit options for second-line treatment. We studied the pattern of drug resistance mutations among 138 Indian patients who experienced failure of nonnucleotide reverse-transcriptase-containing first-line highly active antiretroviral therapy. This study demonstrates a high frequency of drug resistance mutations in human immunodeficiency virus-infected Indians who experience immunologic treatment failure and suggests the need for viral load monitoring.

Spectrum of adverse events after generic HAART in southern Indian HIV-infected patients.

To determine the incidence of clinically significant adverse events after long-term, fixed-dose, generic highly active antiretroviral therapy (HAART) use among HIV-infected individuals in South India, we examined the experiences of 3154 HIV-infected individuals who received a minimum of 3 months of generic HAART between February 1996 and December 2006 at a tertiary HIV care referral center in South India. The most common regimens were 3TC + d4T + nevirapine (NVP) (54.8%), zidovudine (AZT) + 3TC + NVP (14.5%), 3TC + d4T + efavirenz (EFV) (20.1%), and AZT + 3TC + EFV (5.4%). The most common adverse events and median CD4 at time of event were rash (15.2%; CD4, 285 cells/microL) and peripheral neuropathy (9.0% and 348 cells/microL). Clinically significant anemia (hemoglobin <7 g/dL) was observed in 5.4% of patients (CD4, 165 cells/microL) and hepatitis (clinical jaundice with alanine aminotransferase > 5 times upper limits of normal) in 3.5% of patients (CD4, 260 cells/microL). Women were significantly more likely to experience lactic acidosis, while men were significantly more likely to experience immune reconstitution syndrome (p < 0.05). Among the patients with 1 year of follow-up, NVP therapy was significantly associated with developing rash and d4T therapy with developing peripheral neuropathy (p < 0.05). Anemia and hepatitis often occur within 12 weeks of initiating generic HAART. Frequent and early monitoring for these toxicities is warranted in developing countries where generic HAART is increasingly available.

An inexpensive, simple, and manual method of CD4 T-cell quantitation in HIV-infected individuals for use in developing countries

Summary:CD4+ T lymphocytes are currently the most common surrogate marker indicating immune status and disease progression with HIV infection. The cost of monitoring disease progression and response to therapy is still prohibitively expensive. Flow cytometry is the gold standard for the estimation of CD4+, but the high initial investment for this technology and expensive reagents makes it unaffordable for developing countries like India. We evaluated the Coulter cytosphere assay for quantifying CD4+ T lymphocytes in comparison with the standard method, flow cytometry, in 122 HIV-infected individuals. The correlation coefficient of the cytosphere assay compared with that of flow cytometry for CD4+ T lymphocytes was 0.97 (P< 0.0001), with a confidence interval of 0.95 to 0.98. The sensitivity, specificity, positive predictive value, and negative predictive value of the cytosphere assay in enumerating absolute CD4+ T-lymphocyte counts of less than 200/μL were 94.9%, 96.4%, 92.5%, and 97.6%, respectively. This is a simple inexpensive method and has a strong correlation with flow cytometry. Hence, the cytosphere assay can be an alternate to flow cytometry for the estimation of CD4+ T-lymphocyte counts, especially in resource-poor settings of developing countries, for monitoring HIV progression and response to therapy.

A reliable and inexpensive EasyCD4 assay for monitoring HIV-infected individuals in resource-limited settings.

Summary: Serial measurements of absolute CD4+ T-lymphocyte counts are required to initiate and gauge response to therapy and monitor disease progression. Hence, there is an urgent need to evaluate the accuracy and validity of low-cost CD4+ T-cell count assays. Tripotassium EDTA blood specimens from HIV-infected individuals were studied using a novel flow cytometric assay (EasyCD4 assay; Guava Technologies, Hayward, CA) in comparison with standard flow cytometry (FACSCount; Becton Dickinson Immunocytometry Systems, San Jose, CA). The sensitivity, specificity value by EasyCD4 assay in enumerating absolute CD4+ T-cell counts of less than 200 cells/&mgr;L were 95% and 100%, respectively. Bland-Altman analysis showed close agreement, with the EasyCD4 assay yielding CD4+ T-cell counts a mean difference of −26 cells/&mgr;L (95% confidence interval, −96 to 44 cells/&mgr;L) higher than by flow cytometry. Our data suggest that EasyCD4 assay could be a useful alternative assay to conventional flow cytometry, may be appropriate for use in resource-limited settings.

Gender-Based Differences in Treatment and Outcome among HIV Patients in South India

OBJECTIVE To describe gender-based differences in disease progression, treatment, and outcome among patients receiving highly active antiretroviral therapy (HAART) in South India. METHODS Therapy-naïve patients initiating HAART between February 1996 and June 2006 at a tertiary HIV referral center in Chennai, South India, were analyzed using the YRG CARE HIV Observational Database. Patients with 1 year of follow-up after initiating HAART were examined to investigate immunological and clinical outcomes, including the development of adverse events to therapy and opportunistic infections. RESULTS All previously therapy-naïve patients who initiated HAART with at least 1 year of follow-up (n = 1972) were analyzed. At enrollment into care, women had higher CD4 counts, lower hemoglobin, and higher body mass index (BMI) than their male counterparts (p < 0.05). At the time of initiating therapy, women had higher CD4 counts and lower hemoglobin (p < 0.05); women continued to have higher CD4 counts at 12 months (p < 0.05). After 1 year following HAART initiation, significantly more men developed tuberculosis and Pneumocystis jiroveci pneumonia (p < 0.05), more women experienced lactic acidosis and nausea, and more men developed immune reconstitution syndrome (p < 0.05). CONCLUSIONS Significant physiological, immunological, and clinical differences exist between men and women initiating HAART in a resource-limited setting in South India. Future studies should examine whether clinical management strategies should be different for men and women in resource-limited settings.

Multiple NF-κB sites in HIV-1 subtype C long terminal repeat confer superior magnitude of transcription and thereby the enhanced viral predominance.

Background: Viral evolution of HIV-1 is dynamic and moving towards a higher order of replicative fitness. Results: HIV-1 subtype C acquires an extra (4th) NF-κB site to achieve a higher degree of transcription and in turn enhances its replicative fitness and preponderance. Conclusion: Subtype C with an extra NF-κB site adopts a novel strategy of strengthening its promoter to gain fitness. Significance: Learning how the new strains could impact viral prevalence, pathogenesis, and disease management strategies is critical. We demonstrate that at least three different promoter variant strains of HIV-1 subtype C have been gradually expanding and replacing the standard subtype C viruses in India, and possibly in South Africa and other global regions, over the past decade. The new viral strains contain an additional NF-κB, NF-κB-like, or RBEIII site in the viral promoter. Although the acquisition of an additional RBEIII site is a property shared by all the HIV-1 subtypes, acquiring an additional NF-κB site remains an exclusive property of subtype C. The acquired κB site is genetically distinct, binds the p50-p65 heterodimer, and strengthens the viral promoter at the levels of transcription initiation and elongation. The 4-κB viruses dominate the 3-κB “isogenic” viral strains in pairwise competition assays in T-cell lines, primary cells, and the ecotropic human immunodeficiency virus mouse model. The dominance of the 4-κB viral strains is also evident in the natural context when the subjects are coinfected with κB-variant viral strains. The mean plasma viral loads, but not CD4 counts, are significantly different in 4-κB infection suggesting that these newly emerging strains are probably more infectious. It is possible that higher plasma viral loads underlie selective transmission of the 4-κB viral strains. Several publications previously reported duplication or deletion of diverse transcription factor-binding sites in the viral promoter. Unlike previous reports, our study provides experimental evidence that the new viral strains gained a potential selective advantage as a consequence of the acquired transcription factor-binding sites and importantly that these strains have been expanding at the population level.

Pretreatment HIV Drug Resistance and HIV-1 Subtype C Are Independently Associated With Virologic Failure: Results From the Multinational PEARLS (ACTG A5175) Clinical Trial

BACKGROUND Evaluation of pretreatment HIV genotyping is needed globally to guide treatment programs. We examined the association of pretreatment (baseline) drug resistance and subtype with virologic failure in a multinational, randomized clinical trial that evaluated 3 antiretroviral treatment (ART) regimens and included resource-limited setting sites. METHODS Pol genotyping was performed in a nested case-cohort study including 270 randomly sampled participants (subcohort), and 218 additional participants failing ART (case group). Failure was defined as confirmed viral load (VL) >1000 copies/mL. Cox proportional hazards models estimated resistance-failure association. RESULTS In the representative subcohort (261/270 participants with genotypes; 44% women; median age, 35 years; median CD4 cell count, 151 cells/µL; median VL, 5.0 log10 copies/mL; 58% non-B subtypes), baseline resistance occurred in 4.2%, evenly distributed among treatment arms and subtypes. In the subcohort and case groups combined (466/488 participants with genotypes), used to examine the association between resistance and treatment failure, baseline resistance occurred in 7.1% (9.4% with failure, 4.3% without). Baseline resistance was significantly associated with shorter time to virologic failure (hazard ratio [HR], 2.03; P = .035), and after adjusting for sex, treatment arm, sex-treatment arm interaction, pretreatment CD4 cell count, baseline VL, and subtype, was still independently associated (HR, 2.1; P = .05). Compared with subtype B, subtype C infection was associated with higher failure risk (HR, 1.57; 95% confidence interval [CI], 1.04-2.35), whereas non-B/C subtype infection was associated with longer time to failure (HR, 0.47; 95% CI, .22-.98). CONCLUSIONS In this global clinical trial, pretreatment resistance and HIV-1 subtype were independently associated with virologic failure. Pretreatment genotyping should be considered whenever feasible. CLINICAL TRIALS REGISTRATION NCT00084136.