The Impact of Male Partner Circumcision on Women's Health Outcomes.

Medical male circumcision is a proven method of HIV risk reduction in men with no known direct benefit to women. We investigated the benefit of partner circumcision on women's health. We conducted a secondary analysis of 5,029 women enrolled in the Vaginal and Oral Interventions to Control the Epidemic trial across 15 African sites, to look at the impact of partner circumcision status on sexually transmitted infections, pregnancy, frequency of sex, and condom use in women. Of 4,982 participants with a baseline response, 31% had circumcised partners. Women with circumcised partners had a significantly reduced risk of syphilis acquisition, hazard ratio 0.51 (0.26, 1.00), p value = .05. Participants with uncircumcised partners were significantly less likely to have used a condom at the last sex act than the other two groups, adj. relative risk 0.86 (0.80, 0.92), adj. p value < .0001. We found no evidence of sexual risk compensation in women with circumcised partners.

Use of the dapivirine vaginal ring and effect on cervical cytology abnormalities.

OBJECTIVE: We aimed to determine if the dapivirine vaginal ring and the ring device alone (flexible silicone matrix polymer) was associated with the development of cervical cytology abnormalities. DESIGN: Secondary analysis comparing cervical cytology results between two randomized controlled microbicide trials (MTN-020/ASPIRE and MTN-003/VOICE). METHODS: Data from ASPIRE, a phase III, placebo-controlled trial of the dapivirine vaginal ring, were used in this analysis. Cervical cytology smears were evaluated at baseline and at the final visit with product use. We compared cytology results between women randomized to dapivirine versus placebo vaginal ring. We further assessed for the effect of the vaginal ring device on cervical cytology by comparing results with data from the oral placebo arm of VOICE, a prior HIV-1 prevention trial conducted in a similar population. RESULTS: Cervical cytology results for 2394 women from ASPIRE (1197 per study arm) were used in this analysis; median time between baseline and final visit with product use was 22.1 months. Cytology smear findings were comparable between dapivirine and placebo vaginal ring arms: at final visit, normal: 90.6 versus 91.5%, ASC-US//LSIL: 7.8 versus 7.4%, ASC-H/HSIL/AGC/AGC-favor neoplastic: 1.7 versus 1.1%, P = 0.44. Cytology data from VOICE had findings (normal: 87.8%, ASC-US/LSIL: 9.8%, ASC-H/HSIL/AGC/AGC-favor neoplastic: 2.4%) comparable with that of both dapivirine (P = 0.93) and placebo vaginal ring arms (P = 0.24). CONCLUSION: These findings indicate that neither use of the dapivirine vaginal ring nor the vaginal ring device alone, over a period of 2 years, is associated with development of cervical cytology abnormalities that could lead to precancerous or cancerous lesions.

Tenofovir Gel for Prevention of Herpes Simplex Virus Type 2 Acquisition: Findings From the VOICE Trial.

BACKGROUND: Genital infection with herpes simplex virus type 2 (HSV-2) is common and increases risk of human immunodeficiency virus (HIV) transmission and acquisition. Pericoital use of tenofovir (TFV) gel provided protection from HSV-2 acquisition in the CAPRISA 004 study. METHODS: We measured estimate of effect of vaginal TFV 1% gel in preventing HSV-2 acquisition among women in VOICE, randomized, double-blinded, placebo-controlled trial assessing daily use of oral and vaginal TFV for HIV-1 preexposure prophylaxis. The TFV level in plasma at the first quarterly visit was used as a measure of gel use. RESULTS: Of 566 participants at risk for HSV-2 acquisition, 532 (94%) had first-quarter plasma TFV and end-of-study HSV-2 serologic data available. Over a follow-up period of 501 person-years, 92 incident cases of HSV-2 acquisition occurred: 77 were in women with no TFV detected in plasma, and 15 occurred in women with TFV detected in plasma (incidence, 20.6 cases/100 person-years [95% confidence interval [CI], 16.2-25.7] vs 11.9 cases/100 person-years [95% CI, 6.6-19.6], respectively). TFV detection in plasma was associated with a trend toward a reduced risk of HSV-2 seroconversion, with an unadjusted hazard ratio (HR) of 0.59 (95% CI, .34-1.02; P = .060) and a HR adjusted for site, age, having ≥2 male sex partners in the past 3 months, use of hormonal contraception, having anal sex in the past 3 months, and HIV status of 0.60 (95% CI, .33-1.08; P = .086). CONCLUSIONS: Detection of TFV in plasma among TFV gel users was associated with a trend toward a reduced risk of HSV-2 acquisition, after controlling for sexual behavior and HIV-1 acquisition.

Pharmacokinetics of Dapivirine Transfer into Blood Plasma, Breast Milk, and Cervicovaginal Fluid of Lactating Women Using the Dapivirine Vaginal Ring.

Breastfeeding (BF) women are an important population for biomedical HIV prevention strategies, but they are rarely included in trials. The 25-mg dapivirine vaginal ring (VR) reduced women's risk of sexually transmitted HIV infection in two phase 3 trials conducted in Africa. We conducted a phase 1, open-label study (MTN-029/IPM 039) of dapivirine VR use among lactating women in Pittsburgh, PA, and Birmingham, AL, USA. MTN-029/IPM 039 enrolled 16 healthy adult women who had already weaned their infants but were still able to express breast milk. Women were instructed to use the VR continuously for 14 days and provided milk, plasma, and cervicovaginal fluid (CVF) samples for pharmacological analysis. No infants were exposed to the drug, but infant dosage was estimated according to FDA guidance. Adverse events (AEs) were collected at all contacts. The study was completed with 100% participant retention. Median dapivirine concentrations were 676 pg/ml in breast milk, 327 pg/ml in plasma (milk/plasma ratio ∼2.0), and 36.25 ng/mg in CVF. Six participants experienced 10 total AEs, none of which required VR discontinuation. The estimated mean daily infant dosage was 74.3 ng/kg/day. In this first study of dapivirine exposure during lactation, dapivirine VR use was associated with lower concentrations of detectable dapivirine in milk and plasma than in CVF samples and a favorable safety profile. Estimated daily levels of infant dapivirine exposure were also low. Additional studies are needed to evaluate longer periods of dapivirine VR use among BF mother-infant pairs living in regions with higher incidence of sexually transmitted HIV infection. (This study has been registered at ClinicalTrials.gov under registration no. NCT02808949.).

The fourth generation AlereTM HIV Combo rapid test improves detection of acute infection in MTN-003 (VOICE) samples.

BACKGROUND: Early and accurate detection of HIV is crucial when using pre-exposure prophylaxis (PrEP) for HIV prevention to avoid PrEP initiation in acutely infected individuals and to minimize the risk of drug resistance in individuals with breakthrough infection. OBJECTIVE: To determine if fourth-generation antigen/antibody (Ag/Ab) rapid diagnostic tests (RDT) would have detected HIV infection earlier than the third-generation RDT used in MTN-003 (VOICE). STUDY DESIGN: 5029 VOICE participants were evaluated with third-generation Alere Determine™ HIV-1/2, OraQuick ADVANCE® Rapid HIV-1/2, Uni-Gold™ Recombigen® HIV-1/2 and Bio-Rad GS HIV-1/2+O EIA; and fourth-generation Alere Determine™ HIV-1/2 Ag/Ab Combo, Conformité Européene (CE)-Marked Alere™ HIV Combo and Bio-Rad HIV Combo Ag/Ab EIA. Multispot®, GS HIV-1 Western Blot (WB) and Geenius™ (Bio-Rad) were also evaluated. RESULTS: Of 57 antibody-negative pre-seroconversion plasma samples with HIV RNA >20 copies/mL identified, 16 (28%) were reactive by CE-Marked Alere™ HIV Combo (1 Ab; 9 Ag; 6 Ag/Ab reactive) and 4 (7%) by Alere Determine™ HIV-1/2 Ag/Ab Combo (2 Ab; 2 Ag; 0 Ag/Ab reactive) (p=0.0005). Multispot® confirmed only 1 of 16 acute infections while WB and Geenius™ confirmed none. GS HIV Combo Ag/Ab EIA identified 27 of 57 (47%) pre-seroconversion RNA-positive samples. CONCLUSION: In VOICE, 28% of infections missed by current third-generation RDT would have been identified with the use of CE-Marked Alere™ HIV Combo. Geenius™, Multispot® and WB were all insensitive (<10%) in confirming infections detected by fourth-generation assays. An improved diagnostic algorithm that includes a fourth-generation RDT with HIV RNA testing will be essential for efficiently identifying seroconverters on PrEP.

Pharmacological Measures of Treatment Adherence and Risk of HIV Infection in the VOICE Study.

BACKGROUND: None of the 3 regimens tested in the VOICE study showed protection against human immunodeficiency virus (HIV) infection in intent-to-treat analyses. Plasma tenofovir concentrations demonstrated poor adherence to the study product among study subjects. Statistical analyses to explore the causal treatment effect on the prevention of HIV infection among adherent individuals are needed. METHODS: We developed an analytical strategy to evaluate whether conventional covariate adjustment removes confounding and thereby reveals a prevention effect among adherent individuals. We applied this strategy to the VOICE study, using 2 dichotomized proxy measures of product use: detection of tenofovir in plasma at least once during follow-up and detection of tenofovir in plasma at the 3-month follow-up visit. RESULTS: After adjustment for a set of baseline predictors of the risk of HIV transmission, the confounding associated with comparison of adherent individuals in the tenofovir gel arm to placebo recipients was nearly eliminated. The relative risk for a prevention effect among those ever having tenofovir detected was 0.53 (P = .038); the relative risk among those having tenofovir detected at 3 months was 0.40 (P = .045). CONCLUSIONS: A novel regression approach was proposed for causal as-treated analyses in the VOICE study. While intent-to-treat analyses yield null results, this exploratory approach presented evidence suggesting a prevention effect among gel users. CLINICAL TRIALS REGISTRATION: NCT00705679.

Characteristics Associated with HIV Drug Resistance Among Women Screening for an HIV Prevention Trial in KwaZulu-Natal, South Africa.

While the expansion of antiretroviral therapy (ART) in sub-Saharan Africa has reduced morbidity and mortality from HIV/AIDS, it has increased concern about drug resistance. The Microbicide Trials Network 009 study assessed the prevalence of drug-resistance mutations among women at clinical sites in Durban, South Africa who tested seropositive for HIV-1 at screening for the VOICE trial. The objective of this paper was to identify characteristics and behaviors associated with drug resistance. Factors found to be significantly associated with increased resistance were high perceived risk of getting HIV and prior participation in a microbicide trial, a likely proxy for familiarity with the health care system. Two factors were found to be significantly associated with reduced resistance: having a primary sex partner and testing negative for HIV in the past year. Other variables hypothesized to be important in identifying women with resistant virus, including partner or friend on ART who shared with the participant and being given antiretrovirals during pregnancy or labor, or the proxy variable-number of times given birth in a health facility-were not significantly associated. The small number of participants with resistant virus and the probable underreporting of sensitive behaviors likely affected our ability to construct a comprehensive profile of the type of HIV-positive women at greatest risk of developing resistance mutations.

Factors associated with bone mineral density in healthy African women.

UNLABELLED: There is a paucity of normative bone mineral density (BMD) data in healthy African women. Baseline total hip and lumbar spine BMD was measured in premenopausal women. BMD distribution was comparable to that of a reference population and was impacted by several factors including contraception and duration of lactation. INTRODUCTION: Normative data on bone mineral density (BMD) and the cumulative impact of lactation, contraceptive use, and other factors on BMD in healthy African women have not been well studied. OBJECTIVES: The objective of this study was to determine the factors associated with BMD in healthy premenopausal women in Uganda and Zimbabwe. METHODS: Baseline total hip (TH) and lumbar spine (LS) BMD was measured by dual x-ray absorptiometry in 518 healthy, premenopausal black women enrolling in VOICE, an HIV-1 chemoprevention trial, at sites in Uganda and Zimbabwe. Contraceptive and lactation histories, physical activity assessment, calcium intake, and serum vitamin D levels were assessed. Independent factors associated with BMD were identified using an analysis of covariance model. RESULTS: The study enrolled 331 women from Zimbabwe and 187 women from Uganda. Median age was 29 years (IQR 25, 32) and median body mass index (BMI) was 24.8 kg/m(2) (IQR 22.2, 28.6). In univariate analyses, lower TH BMD values were associated with residence in Uganda (p < 0.001), lower BMI (p < 0.001), and any use of and duration of depot-medroxyprogresterone acetate. Use of oral contraceptives, progestin-only implants, and higher physical activity levels were protective against reduced BMD. Similarly, lower LS BMD values were associated with these same factors but also higher parity and history of breastfeeding. In a multivariable analysis, lower TH and LS BMD values were associated with enrollment in Uganda, lower BMI, and lower physical activity level; contraceptive use was associated with lower spine BMD, and breastfeeding contributed to lower total hip BMD. CONCLUSIONS: Among healthy premenopausal women, TH and LS BMD was higher in Zimbabwe than Uganda. Additional factors independently associated with BMD included BMI, physical activity level, contraceptive use, and lactation.

Prevalence of HIV-1 drug resistance among women screening for HIV prevention trials in KwaZulu-Natal, South Africa (MTN-009).

BACKGROUND: A major concern with using antiretroviral (ARV)-based products for HIV prevention is the potential spread of drug resistance, particularly from individuals who are HIV-infected but unaware of their status. Limited data exist on the prevalence of HIV infection or drug resistance among potential users of ARV-based prevention products. METHODS: A cross-sectional study of reproductive-aged women who presented to screen for an HIV prevention trial was conducted at 7 clinical sites in Durban, South Africa. CD4+T cell counts, HIV-1 RNA levels and population sequencing of the protease and reverse transcriptase genes were performed for all women with 2 positive HIV rapid tests. Resistance mutations were identified using the Stanford Calibrated Population Resistance Tool. RESULTS: Of the 1073 evaluable women, 400(37%) were confirmed as HIV-infected. Of those, plasma HIV-1 RNA was detectable in 365/400(91%) and undetectable(<40 copies/ml) in 35/400(9%) women. 156 women(39%) were eligible for antiretroviral therapy (CD4+T cell counts<350 cells/mm(3)) and 50(13%) met criteria for AIDS(CD4<200 cells/mm(3)). Of 352 plasma samples(>200 copies/ml) analyzed for drug resistance, 26(7.4%) had nucleoside reverse transcriptase inhibitor (NRTI), non-nucleoside reverse transcriptase inhibitor (NNRTI) or protease inhibitor (PI) drug resistance mutations. Among those with resistance, 18/26 participants(62%) had single-class NNRTI resistance and 5/26(19%) had dual-class NRTI/NNRTI. Major mutations in reverse transcriptase included K65R(n = 1), L74I(n = 1), K103N(n = 19), V106M(n = 4), Y181C(n = 2), M184V(n = 4), and K219E/R(n = 2). Major PI-resistance mutations were rare: M46L(n = 1) and I85V(n = 1). All participants were infected with subtype C virus, except one infected with subtype A. CONCLUSIONS: In women from Durban, South Africa screening for an HIV prevention trial, the HIV prevalence was high (37%) and HIV drug resistance prevalence was above 5%. This study highlights the potential challenges faced when implementing an ARV-based prevention product that overlaps with first-line antiretroviral therapy. Effective screening to exclude HIV infection among women interested in uptake of ARV-based HIV prevention will be essential in limiting the spread of ARV resistance.

Appropriateness of hydroxyethylcellulose gel as a placebo control in vaginal microbicide trials: a comparison of the two control arms of HPTN 035.

OBJECTIVE: To compare the 2 control arms of HPTN 035 [a hydroxyethylcellulose (HEC) gel control arm and a no-gel control arm] to assess the behavioral effects associated with gel use and direct causal effects of the HEC gel on sexually transmitted infections (STIs), pregnancy, and genital safety. DESIGN: Randomized trial with 1 blinded (HEC gel) and 1 open-label (no-gel) control arms. METHODS: HIV-uninfected, sexually active women were randomized into the HEC gel arm (n = 771) and into the no-gel arm (n = 772) in 5 countries. Participants in the HEC gel arm were instructed to insert the study gel intravaginally <1 hour before each vaginal sex act. Data on sexual behavior, adherence, safety, pregnancy, and STIs were collected quarterly for 12-30 months of follow-up. RESULTS: During follow-up, mean reported condom use in the past week was significantly higher in the no-gel arm (81% versus 70%, P < 0.001). There were no significant differences, after adjusting for this differential condom use, between the 2 arms in the rates of genital safety events, pregnancy outcomes, or STIs, including HIV-1. CONCLUSIONS: In this large randomized trial, we found no significant differences between the no-gel and HEC gel arms in the rates of genital safety events, pregnancy outcomes, or STIs. These results aid interpretation of the results of previous vaginal microbicide trials that used the HEC gel as a control. The HEC gel is suitable as a control for ongoing and future vaginal microbicide studies.

Utility of colposcopy in a phase 2 portion of a microbicide clinical trial of BufferGel and 0.5% PRO 2000 Gel.

BACKGROUND: The majority of new HIV infections are acquired through heterosexual transmission. There is urgent need for prevention methods to compliment behavior change and condom use. Topical microbicide represent a potential strategy for reduction of HIV transmission in women. METHODS: Monthly Colposcopy evaluations were performed during pelvic examinations among 299 women enrolled in the Phase 2 portion of HPTN 035 study at four sites (1 in USA, 3 in Southern Africa). This was a phase 2/2b, multisite, randomized, and controlled clinical trial with four arms: BufferGel, 0.5% PRO2000 Gel, placebo gel and no gel. At two of the sites, pelvic examinations were conducted by the use of naked eye without colposcopy. RESULTS: A colposcopy finding of any kind was detected in 48% of participants at baseline compared to 40% at 3 months (p =0.04). The lower rates were also observed in vaginal discharge (22% at baseline, 16% at 3 months, p=0.06), erythema (15% at baseline, 8% at 3 months, p=0.004). The trend towards significance at p=0.05 disappear when utilizing stringent statistical significance levels. A pelvic finding of any kind was detected in 71% of colposcopy participants compared to 41% of participants who had naked eye examination only conducted at two sites that performed both colposcopy and naked eye without colposcopy. Use of colposcopy yielded significantly higher rates of participants with deep epithelial disruption, erythema and ecchymosis. We observed no cases of incident Chlamydia, Gonorrhea, or Syphilis during the three month follow up. There were 2 cases of incident HIV during 3-month study period neither of which was associated with any abnormal colposcopy evaluation findings. CONCLUSION: No safety signals were observed in the 4 study arms, allowing seamless transition from phase 2 to 2b. Colposcopy utility in microbicide clinical trials has minimal value given high rates of background noise findings of no relevant clinical significance.

HIV incidence among non-pregnant women living in selected rural, semi-rural and urban areas in KwaZulu-Natal, South Africa.

The province of KwaZulu-Natal has the highest prevalence of HIV in South Africa, particularly among young women. In order to more closely examine the HIV prevalence and incidence in non-pregnant women from rural, semi-rural and urban areas, data from 5,753 women screened for enrolment into three HIV prevention studies were combined and analysed. The prevalence of HIV infection was 43% at screening. HIV incidence among the 2,523 enrolled HIV-negative women was determined every quarter, and sexual behaviour and socio-demographic data were collected as per respective protocols. During follow-up, 211 women seroconverted (6.6/100 women years). Multivariate analysis found that seroconversion rates were highest among women who were ≤24 years old, single and not cohabiting, and who had incident sexually transmitted infections. The epidemic in KwaZulu-Natal calls for targeted HIV prevention interventions among those at highest risk of acquiring or transmitting infection.

Risk factors for incidence of sexually transmitted infections among women in South Africa, Tanzania, and Zambia: results from HPTN 055 study.

OBJECTIVE: To determine risk factors for sexually transmitted infections (STIs) among women in Durban and Hlabisa (South Africa), Moshi (Tanzania), and Lusaka (Zambia). STUDY DESIGN: Between 2003 and 2004, 958 women at risk of STIs were enrolled in a 1-year prospective study. They were interviewed at each monthly visit, and samples for STI testing were collected during quarterly and other visits when clinically indicated. RESULTS: The incidence of infections as measured in person-years at risk (PYAR) was as follows: overall trichomoniasis, 31.9/100 PYAR; chlamydial infection in South Africa, 19.5/100 PYAR; chlamydial infection in Tanzania and Zambia, 4.9/100 PYAR; gonorrhea in South Africa, 16.5/100 PYAR; gonorrhea in Tanzania and Zambia, 5.3/100 PYAR; overall syphilis, 7.5/100 PYAR; and overall HIV, 3.8/100 PYAR. The incidence of most STIs was highest among the South African sites, where chlamydial infection and gonorrhea were detected by using a more sensitive assay. Independent risk factors included age, hormonal contraceptive methods, and measures of sexual behavior, including number of sex partners and occurrence of anal sex in the past 3 months. Women with incident HIV infection were at increased risk of chlamydial infection [odds ratio (OR) = 5.5, 95% confidence interval (CI): 2.0-15.2]and gonorrhea (OR = 5.7, 95% CI: 1.9-17.0) in South African sites. Despite ongoing counseling during the study, high-risk sexual behaviors were common, and consistent condom use remained low. CONCLUSIONS: The incidence of STIs, including HIV, was high among women in this study. These findings highlight the urgent need for effective HIV/STI prevention programs in this population.

The value of site preparedness studies for future implementation of phase 2/IIb/III HIV prevention trials: experience from the HPTN 055 study.

OBJECTIVES: To evaluate the preparedness for phase 2/IIb/III microbicide trials at 4 clinical trial sites: Durban and Hlabisa (South Africa), Lusaka (Zambia), and Moshi (Tanzania). DESIGN: A prospective cohort study was undertaken to assess site suitability for microbicide efficacy studies. Study objectives included assessing sites' ability to recruit and retain high-risk women with the appropriate HIV incidence rates needed to conduct microbicide efficacy studies. METHODS: Nine hundred fifty-eight consenting women were enrolled and followed for up to 1 year. Demographic, behavioral, laboratory, and clinical data were collected to determine the incidence rates of HIV, sexually transmitted infections, and pregnancy. RESULTS: Accrual was completed in 6.3, 6.7, 7.1, and 8.3 months in Durban, Hlabisa, Moshi, and Lusaka, respectively. The highest month 12 participant retention rate was recorded in Durban (97%), followed by Hlabisa (94%), Moshi (86%), and Lusaka (93%). Mean overall age of enrolled participants was 28.6 years (ranging from 27.0 to 32.2 years) across sites. Despite condom counseling, rates of condom use were slightly lower at study end. Pregnancy incidence in the study as a whole was 20.2 per 100 women-years (wy). Overall HIV prevalence was 32.5%, and overall HIV incidence was 3.8 per 100 wy (95% confidence interval [CI]: 2.6 to 5.2). HIV incidence per site was 5.3 per 100 wy in Durban (95% CI: 2.7 to 9.2), 6.2 per 100 wy in Hlabisa (95% CI: 3.4 to 10.5); 2.6 per 100 wy in Lusaka (95% CI: 1.0 to 5.8), and 1.4 per 100 wy in Moshi (95% CI: 0.3 to 4.0). CONCLUSIONS: Preparatory studies provide accurate local estimates of HIV incidence, recruitment and retention rates, and behavioral characteristics of targeted populations for large-scale clinical trials. Determining these factors allows for better preparation for design, sample size, and appropriate population for future selection of trial sites. Because of the lower than expected HIV incidence observed at the Moshi site, only the South African and Zambian sites were selected for the phase 2/IIb trial.

The acceptability of an investigational vaginal microbicide, PRO 2000 Gel, among women in a phase I clinical trial.

PURPOSE: Vaginal microbicides will provide a woman-initiated prevention strategy that could substantially reduce rates of HIV infection. The acceptability of microbicides will greatly influence the use and, hence, effectiveness of such products. In this study, the acceptability of an investigational microbicide, PRO 2000 Gel (Indevus Pharmaceuticals, Inc., Lexington, MA), was assessed, and women's opinions about microbicides and their potential for real world use were gathered. METHODS: Quantitative and qualitative data were collected from 30 U.S. and 33 South African women. All sexually active HIV-uninfected women and all sexually abstinent HIV-infected women participating in this phase I clinical trial stated in a survey that they would use PRO 2000 Gel if they had reason to be concerned about HIV and the product were available. Qualitative data, however, provided insight into the nuances of acceptability ratings. Women rated product safety, ease of use, and positive effects on sexual pleasure among the most important characteristics of acceptable microbicides. RESULTS: Opinions regarding product leakage, contraceptive capability, and the ability to be used without partners noticing, as well as characteristics of the product itself, varied substantially based on the context of sex and perceptions of risk within each individual woman's life. CONCLUSIONS: As microbicide development continues and the first investigational products move into efficacy trials, the needs and preferences of those women who constitute the potential users of microbicides become paramount. Providing woman-initiated microbicides that are safe, easy to use, and pleasurable will be key to the impact these products will have on the AIDS epidemic worldwide.