Jessica E. Haberer

Antiretroviral Prophylaxis for HIV Prevention in Heterosexual Men and Women

BACKGROUND Antiretroviral preexposure prophylaxis is a promising approach for preventing human immunodeficiency virus type 1 (HIV-1) infection in heterosexual populations. METHODS We conducted a randomized trial of oral antiretroviral therapy for use as preexposure prophylaxis among HIV-1-serodiscordant heterosexual couples from Kenya and Uganda. The HIV-1-seronegative partner in each couple was randomly assigned to one of three study regimens--once-daily tenofovir (TDF), combination tenofovir-emtricitabine (TDF-FTC), or matching placebo--and followed monthly for up to 36 months. At enrollment, the HIV-1-seropositive partners were not eligible for antiretroviral therapy, according to national guidelines. All couples received standard HIV-1 treatment and prevention services. RESULTS We enrolled 4758 couples, of whom 4747 were followed: 1584 randomly assigned to TDF, 1579 to TDF-FTC, and 1584 to placebo. For 62% of the couples followed, the HIV-1-seronegative partner was male. Among HIV-1-seropositive participants, the median CD4 count was 495 cells per cubic millimeter (interquartile range, 375 to 662). A total of 82 HIV-1 infections occurred in seronegative participants during the study, 17 in the TDF group (incidence, 0.65 per 100 person-years), 13 in the TDF-FTC group (incidence, 0.50 per 100 person-years), and 52 in the placebo group (incidence, 1.99 per 100 person-years), indicating a relative reduction of 67% in the incidence of HIV-1 with TDF (95% confidence interval [CI], 44 to 81; P<0.001) and of 75% with TDF-FTC (95% CI, 55 to 87; P<0.001). Protective effects of TDF-FTC and TDF alone against HIV-1 were not significantly different (P=0.23), and both study medications significantly reduced the HIV-1 incidence among both men and women. The rate of serious adverse events was similar across the study groups. Eight participants receiving active treatment were found to have been infected with HIV-1 at baseline, and among these eight, antiretroviral resistance developed in two during the study. CONCLUSIONS Oral TDF and TDF-FTC both protect against HIV-1 infection in heterosexual men and women. (Funded by the Bill and Melinda Gates Foundation; Partners PrEP ClinicalTrials.gov number, NCT00557245.).

Mobile phone technologies improve adherence to antiretroviral treatment in a resource-limited setting: a randomized controlled trial of text message reminders.

Objective:There is limited evidence on whether growing mobile phone availability in sub-Saharan Africa can be used to promote high adherence to antiretroviral therapy (ART). This study tested the efficacy of short message service (SMS) reminders on adherence to ART among patients attending a rural clinic in Kenya. Design:A randomized controlled trial of four SMS reminder interventions with 48 weeks of follow-up. Methods:Four hundred and thirty-one adult patients who had initiated ART within 3 months were enrolled and randomly assigned to a control group or one of the four intervention groups. Participants in the intervention groups received SMS reminders that were either short or long and sent at a daily or weekly frequency. Adherence was measured using the medication event monitoring system. The primary outcome was whether adherence exceeded 90% during each 12-week period of analysis and the 48-week study period. The secondary outcome was whether there were treatment interruptions lasting at least 48 h. Results:In intention-to-treat analysis, 53% of participants receiving weekly SMS reminders achieved adherence of at least 90% during the 48 weeks of the study, compared with 40% of participants in the control group (P = 0.03). Participants in groups receiving weekly reminders were also significantly less likely to experience treatment interruptions exceeding 48 h during the 48-week follow-up period than participants in the control group (81 vs. 90%, P = 0.03). Conclusion:These results suggest that SMS reminders may be an important tool to achieve optimal treatment response in resource-limited settings.

Unraveling the divergent results of pre-exposure prophylaxis trials for HIV prevention.

Although the balance of recent evidence supports the efficacy of antiretroviral (ARV)-based pre-exposure prophylaxis (PrEP) against HIV-1 infection, recent negative trial results are perplexing. Of seven trials with available HIV endpoints, three different products have been tested: tenofovir 1% vaginal gel, oral tenofovir disoproxil fumarate (TDF) tablets, and TDF/emtricitabine tablets. Six of these trials were conducted exclusively in sub-Saharan Africa; all found the products to be well tolerated, and four demonstrated effectiveness. Furthermore, the HIV Prevention Trial Network (HPTN) 052 trial recently confirmed that antiretroviral treatment leads to 96% reduction in transmission to HIV-negative partners in HIV-serodiscordant couples. These results, along with human and animal data, provide substantial evidence for the efficacy of antiretroviral-based HIV prevention. Yet assessment of oral TDF/emtricitabine in the FEM-PrEP study and of oral and vaginal tenofovir in the Microbicide Trial Network (MTN)-003 trial (VOICE) was stopped for futility. How do we make sense of these discrepant results? We believe that adherence is a key factor, although it cannot be the only factor. Expanding upon a recent editorial in the Lancet, we discuss the impact of suboptimal product adherence on PrEP efficacy in the context of variable drug concentration at the exposure site, integrity of the vaginal epithelium, and the role of acute infection.

Interventions to increase antiretroviral adherence in sub-Saharan Africa: a systematic review of evaluation studies

The success of potent antiretroviral treatment for HIV infection is primarily determined by adherence. We systematically review the evidence of effectiveness of interventions to increase adherence to antiretroviral treatment in sub-Saharan Africa. We identified 27 relevant reports from 26 studies of behavioural, cognitive, biological, structural, and combination interventions done between 2003 and 2010. Despite study diversity and limitations, evidence suggests that treatment supporters, directly observed therapy, mobile-phone text messages, diary cards, and food rations can effectively increase adherence in sub-Saharan Africa. However, some interventions are unlikely to have large or lasting effects, and others are effective only in specific settings. These findings emphasise the need for more research, particularly for randomised controlled trials, to examine the effect of context and specific features of intervention content on effectiveness. Future work should assess intervention targeting and selection of interventions based on behavioural theories relevant to sub-Saharan Africa.

What's love got to do with it? Explaining adherence to oral antiretroviral pre-exposure prophylaxis for hiv-serodiscordant couples

Objective:Adherence may be the “Achilles heel” of pre-exposure prophylaxis (PrEP), a promising biomedical approach to HIV prevention. This article presents an explanation of PrEP adherence for African serodiscordant couples derived from qualitative data. Design:Explaining quantitative findings is one way qualitative investigation contributes to research in medicine and public health. This qualitative interview study was nested in the Partners PrEP Study, a phase III randomized trial evaluating oral tenofovir and emtricitabine/tenofovir PrEP to prevent HIV acquisition by HIV-uninfected partners in serodiscordant heterosexual couples. Methods:In-depth qualitative interviews were provided by 60 Partners PrEP Study participants in Uganda. Interviews used open-ended questions eliciting information on adherence experiences, barriers, and facilitators. An inductive approach informed by grounded theory methodology was used to analyze study data. Results:The proposed explanation may be summarized as follows. Serodiscordance destabilizes couples, as the HIV-negative partner reacts with anger, fear, and sadness to the implication of infidelity represented by HIV infection. A “discordance dilemma” ensues, as the desire to avoid acquiring HIV and the advantages of preserving the relationship become competing priorities. PrEP is seen as a solution—a means of safeguarding health without ending the relationship. PrEP users benefit from the support of partners, who reinforce adherence. Where discord in the relationship persists, adherence suffers. Conclusions:PrEP adherence in serodiscordant couples may be understood as a function of the desire to reduce risk although preserving a partnered relationship. PrEP use in stable couples may be associated with improved adherence and thus, greater effectiveness.

Psychological Trauma and PTSD in HIV-Positive Women: A Meta-Analysis

Women bear an increasing burden of the HIV epidemic and face high rates of morbidity and mortality. Trauma has been increasingly associated with the high prevalence and poor outcomes of HIV in this population. This meta-analysis estimates rates of psychological trauma and posttraumatic stress disorder (PTSD) in HIV-positive women from the United States. We reviewed 9,552 articles, of which 29 met our inclusion criteria, resulting in a sample of 5,930 individuals. The findings demonstrate highly disproportionate rates of trauma exposure and recent PTSD in HIV-positive women compared to the general population of women. For example, the estimated rate of recent PTSD among HIV-positive women is 30.0% (95% CI 18.8–42.7%), which is over five-times the rate of recent PTSD reported in a national sample of women. The estimated rate of intimate partner violence is 55.3% (95% CI 36.1–73.8%), which is more than twice the national rate. Studies of trauma-prevention and trauma-recovery interventions in this population are greatly needed.ResumenLas mujeres enfrentan un incremento en la epidemia de VIH y altos índices de morbilidad y mortalidad. El trauma psicológico ha sido cada vez más asociado con la alta prevalencia y los resultados pobres de VIH en esta población. El presente metaanálisis estima la tasa de trauma y Trastorno por Estrés Postraumático (TPEP) en mujeres estadounidenses. Fueron revisados 9,552 artículos de los cuales 29 cumplieron los criterios, resultando en una muestra total de 5,930 individuos. Los resultados demuestran una tasa desproporcionalmente alta de exposición a trauma y reciente TPEP en mujeres VIH positivas en comparación con la población general de mujeres estadounidenses. La tasa estimada de reciente TPEP entre mujeres VIH positivas es 30.0% (95% IC 18.8–42.7%), lo cual es cinco veces la tasa de reciente TPEP reportada en una muestra nacional de mujeres. La tasa estimada de violencia del compañero íntimo (VCI) es 55.3% (95% IC 36.1–73.8%), lo cual es más del doble de la tasa nacional. Estudios de prevención de trauma e intervenciones de recuperación de trauma en esta población son enormemente necesitados.

The Chinese free antiretroviral treatment program: challenges and responses.

To respond to the HIV/AIDS epidemic in China, the National Center for AIDS/STD Control and Prevention established the Division of Treatment and Care in late 2001. The pilot for the National Free ART Program began in Henan Province in 2002, and the program fully began in 2003. Treatment efforts initially focused on patients infected through illicit blood and plasma donation in the mid-1990s and subsequently expanded to include HIV-infected injection drug users, commercial sex workers, pregnant women, and children. The National Free ART Database was established in late 2004, and includes data on current patients and those treated before 2004. Over 31 000 adult and pediatric patients have been treated thus far. Challenges for the program include integration of drug treatment services with ART, an under-resourced health care system, co-infections, stigma, discrimination, drug resistance, and procurement of second-line ART. The merging of national treatment and care, epidemiologic, and drug resistance databases will be critical for a better understanding of the epidemic, for earlier identification of patients requiring ART, and for improved patient follow-up. The Free ART Program has made considerable progress in providing the necessary care and treatment for HIV-infected people in China and has strong government support for continued improvement and expansion.

HIV protective efficacy and correlates of tenofovir blood concentrations in a clinical trial of prep for HIV prevention

Background:Antiretroviral pre-exposure prophylaxis (PrEP) is a novel HIV prevention strategy for which adherence is a known determinant of efficacy. Blood concentrations of PrEP medications are one objective marker of adherence. Methods:In a placebo-controlled PrEP efficacy trial of tenofovir disoproxil fumarate (TDF) and TDF with emtricitabine (FTC/TDF) among 4747 African women and men with an HIV-infected partner, we measured plasma tenofovir concentrations from participants in the active PrEP arms: 29 HIV seroconverters (cases) and 196 randomly selected controls who remained uninfected. Results:Among controls, 71% of visits had tenofovir concentrations >40 ng/mL, consistent with steady-state daily dosing, compared with 21% of cases at the visit HIV was first detected. Pill count data indicated that 96% of controls and 66% of cases had >80% adherence for these same visits. The estimated protective effect of PrEP against HIV, based on concentrations >40 ng/mL, was 88% (95% confidence interval: 60 to 96, P < 0.001) for individuals receiving TDF and 91% (95% confidence interval: 47 to 98, P = 0.008) for individuals receiving FTC/TDF. Controls had consistent patterns of PrEP concentrations during follow-up; among the 81% with concentrations >40 ng/mL at month 1, 75% maintained this concentration at month 12. Only 5 of 29 seroconverters seemed to be consistently adherent to PrEP. Tenofovir concentrations >40 ng/mL were associated with older age and shorter time on study; concentrations ⩽40 ng/mL occurred more commonly when participants reported no sex with their HIV-infected partner. Conclusions:Plasma concentrations of tenofovir consistent with daily dosing were highly predictive of protection from HIV acquisition. Most of those who took PrEP seemed to have high and consistent adherence.

High Acceptability of HIV Pre-exposure Prophylaxis but Challenges in Adherence and Use: Qualitative Insights from a Phase I Trial of Intermittent and Daily PrEP in At-Risk Populations in Kenya

This paper used qualitative methods to explore experiences of men who have sex with men and female sex workers in Nairobi and Mtwapa, Kenya, who used oral pre-exposure prophylaxis (PrEP) for HIV prevention as part of a four-month trial of safety, acceptability and adherence. Fifty-one of 72 volunteers who took part in a randomized, placebo-controlled, blinded trial that compared daily and intermittent dosage of PrEP underwent qualitative assessments after completing the trial. Analyses identified three themes: (i) acceptability of PrEP was high, i.e. side effects were experienced early in the study but diminished over time, however characteristics of pills could improve comfort and use; (ii) social impacts such as stigma, rumors, and relationship difficulties due to being perceived as HIV positive were prevalent; (iii) adherence was challenged by complexities of daily life, in particular post-coital dosing adherence suffered from alcohol use around time of sex, mobile populations, and transactional sex work. These themes resonated across dosing regimens and gender, and while most participants favored the intermittent dosing schedule, those in the intermittent group noted particular challenges in adhering to the post-coital dose. Culturally appropriate and consistent counseling addressing these issues may be critical for PrEP effectiveness.

Safety and Adherence to Intermittent Pre-Exposure Prophylaxis (PrEP) for HIV-1 in African Men Who Have Sex with Men and Female Sex Workers

Background Little is known about safety of and adherence to intermittent HIV PrEP regimens, which may be more feasible than daily dosing in some settings. We present safety and adherence data from the first trial of an intermittent PrEP regimen among Kenyan men who have sex with men (MSM) and female sex workers (FSW). Methods/Principal Findings MSM and FSW were randomized to daily oral FTC/TDF or placebo, or intermittent (Monday, Friday and within 2 hours after sex, not to exceed one dose per day) oral FTC/TDF or placebo in a 2∶1∶2∶1 ratio; volunteers were followed monthly for 4 months. Adherence was assessed with the medication event monitoring system (MEMS). Sexual activity data were collected via daily text message (SMS) queries and timeline followback interviews with a one-month recall period. Sixty-seven men and 5 women were randomized into the study. Safety was similar among all groups. Median MEMS adherence rates were 83% [IQR: 63–92] for daily dosing and 55% [IQR:28–78] for fixed intermittent dosing (p = 0.003), while adherence to any post-coital doses was 26% [IQR:14–50]. SMS response rates were low, which may have impaired measurement of post-coital dosing adherence. Acceptability of PrEP was high, regardless of dosing regimen. Conclusions/Significance Adherence to intermittent dosing regimens, fixed doses, and in particular coitally-dependent doses, may be more difficult than adherence to daily dosing. However, intermittent dosing may still be appropriate for PrEP if intracellular drug levels, which correlate with prevention of HIV acquisition, can be attained with less than daily dosing and if barriers to adherence can be addressed. Additional drug level data, qualitative data on adherence barriers, and better methods to measure sexual activity are necessary to determine whether adherence to post-coital PrEP could be comparable to more standard regimens. Trial Registration ClinicalTrials.gov NCT00971230