Background

We previously reported that integrating antiretroviral therapy (ART) with tuberculosis treatment reduces mortality. However, optimal time to initiate ART during tuberculosis treatment remains contentious.

Methods

To address this, we conducted a 3-arm, open-label randomized controlled trial in South Africa in acid-fast bacilli smear positive patients (n=642) with HIV and CD4+ counts <500 cells/mm3. Findings on the early therapy group (ART initiated within 4 weeks of tuberculosis treatment initiation, n=214) and late therapy group (ART initiated within the first 4 weeks of the continuation phase of tuberculosis treatment, n=215) are presented here.

Results

Median CD4+ count and viral load at baseline was 150 cells/mm3 and 161000 copies/ml, being similar in both groups. Incidence rate of AIDS or death was 6.9 (18/259.4) and 7.8 (19/244.2) per 100 person-years in the early and late therapy groups respectively (Incidence Rate Ratio (IRR)=0.89; 95%Confidence Interval (95%CI): 0.44,1.79; P=0.73). However, in patients with CD4+ counts <50 cells/mm3, the incidence rates of AIDS or death were 8.5 (early) and 26.3 (late) per 100 person-years (IRR=0.32; 95%CI: 0.07,1.13; P=0.06). Immune reconstitution inflammatory syndrome (IRIS) incidence rates were 20.2 (early) and 7.7 (late) per 100 person-years (IRR=2.62; 95%CI: 1.48,4.82; P<0.001). Adverse events requiring antiretroviral drug switches occurred in 10 (early) and 1 (late) patients (P=0.006).

Conclusions

The benefits of AIDS-free survival balanced against the risks of IRIS and ART-related adverse events, support early ART initiation in patients with CD4+ counts <50 cells/mm3 and deferred ART initiation to the continuation phase of tuberculosis treatment when CD4+ counts are higher.

Introduction

Integrating HIV and TB treatment can reduce mortality substantially. Practical barriers to treatment integration still exist and include safety concerns related to concomitant drug use because of drug interactions and additive toxicities. Altered therapeutic concentrations may influence the chances of treatment success or toxicity.

Areas covered

The available data on drug-drug interactions between the rifamycin class of anti-mycobacterials and the non-nucleoside reverse transcriptase inhibitor and the protease inhibitor classes of anti-retrovirals are discussed with recommendations for integrated use. Additive drug toxicities, the impact of immune reconstitution inflammatory syndrome (IRIS) and the latest data on survival benefits of integrating treatment are elucidated.

Expert opinion

Deferring treatment of HIV to avoid drug-interactions with TB treatment or the occurrence of IRIS is not necessary. In the integrated management of TB/HIV co-infection, rational drug combinations aimed at reducing toxicities while effecting TB cure and suppressing HIV viral load are possible.

The CAPRISA 004 trial assessed effectiveness and safety of a 1% vaginal gel formulation of tenofovir, a nucleotide reverse transcriptase inhibitor, for the prevention of HIV acquisition in women. A double-blind, randomized controlled trial was conducted comparing tenofovir gel (n=445) with placebo gel (n=444) in sexually active, HIV-uninfected 18-40 year-old women in urban and rural KwaZulu-Natal, South Africa HIV serostatus, safety, sexual behavior and gel and condom use were assessed at monthly follow-up visits for 30 months. HIV incidence in the tenofovir gel arm was 5.6 per 100 women-years (wy), i.e. person time of study observation, (38/680.6wy) compared to 9.1 per 100 wy (60/660.7wy) in the placebo gel arm (Incidence Rate Ratio (IRR)=0.61; p=0.017).In high adherers (gel adherence >80%), HIV incidence was 54% lower (p=0.025) in the tenofovir gel arm. In intermediate adherers (gel adherence 50-80%) and low adherers (gel adherence < 50%) the HIV incidence reduction was 38% and 28% respectively. Tenofovir gel reduced HIV acquisition by an estimated 39% overall, and by 54% in women with high gel adherence. No increase in the overall adverse event rates was observed. There were no changes in viral load and no tenofovir resistance in HIV seroconvertors. Tenofovir gel could potentially fill an important HIV prevention gap, especially for women unable to successfully negotiate mutual monogamy or condom use.

Despite high mortality rates in tuberculosis patients with HIV co-infection, there is continued controversy on when to initiate antiretroviral therapy (ART) in these patients.

Methods

We conducted an open-label randomized controlled trial in Durban, South Africa to determine optimal timing of ART initiation in relation to TB treatment. Acid-fast bacilli (AFB) smear positive tuberculosis patients with HIV infection and CD4+ counts <500 cells/mm3 (n=642) were randomized to one of two integrated treatment arms (ART initiation during tuberculosis treatment) or to a sequential treatment arm (ART initiation upon tuberculosis treatment completion). Participants received standard tuberculosis therapy, cotrimoxazole prophylaxis and once daily didanosine, lamivudine and efavirenz ART regimen. The primary endpoint was all-cause mortality.

Results

This analysis compares data from the sequential treatment arm and the combined integrated treatment arms up to 1 September 2008, when the Safety Monitoring Committee recommended halting the sequential treatment arm. Demographic, clinical and laboratory characteristics at baseline and adverse event rates during follow-up were similar in the study arms. Mortality was 56% lower (hazard ratio: 0.44; 95% Confidence Interval: 21% to 75%; p = 0.003) in the integrated arm (5.4 per 100 person-years (25 deaths; n=429)) compared to sequential arm (12.1 per 100 person-years (27 deaths; n=213)). Mortality rates were lower regardless of CD4+ count level.

Conclusions

Initiating ART during tuberculosis treatment in AFB positive patients with HIV co-infection and CD4+ counts <500 cells/mm3 significantly improves survival and provides further impetus for the integration of tuberculosis and AIDS services.

Background

Young women in sub-Saharan Africa bear a disproportionate burden of HIV infection compared to men but have limited options to reduce their HIV risk. Microbicides could fill an important HIV prevention gap for sexually active women who are unable to successfully negotiate mutual monogamy or condom use.

Purpose

This paper describes the baseline sample characteristics in the CAPRISA 004 trial which assessed the safety and effectiveness of the vaginal microbicide, 1% tenofovir gel for HIV prevention in South Africa.

Methods

This analysis assessed the baseline demographic, clinical and sexual behavior data of women screened and enrolled into the trial. The characteristics were summarized using descriptive summary measures; expressed as means and percent for categorical variables.

Results

HIV prevalence at screening was 25.8% [95% Confidence Interval (CI):23.9-27.7). Of the 889 eligibly enrolled women who contributed follow-up data, rural participants recruited from a family planning (FP) clinic were younger, more likely to be living apart from their regular partner, reported lower coital frequency, had lower condom use (p < 0.001). In contrast, urban participants recruited from a sexually transmitted disease (STD) clinic reported higher numbers of lifetime sexual partners, new partners in the last 30 days and receiving money in exchange for sex (p < 0.001).

Conclusion

The populations selected provide suitable diverse target groups for HIV prevention intervention studies.

Trial registration

ClinicalTrials.gov: NCT 00441298