Project description:Feminizing hormone therapy (FHT) may interact with human immunodeficiency virus preexposure prophylaxis (PrEP). We found that transgender women who took FHT exhibited a 7-fold lower rectal tissue ratio of PrEP's active metabolites vs competing deoxynucleotides compared to cisgender women and men (P = .03) that inversely correlated with estradiol (? = -0.79; P < .05). Thus, FHT may negatively impact PrEP efficacy. Clinical Trials Registration . NCT02983110.
Project description:BackgroundLong-acting injectable (LAI) human immunodeficiency virus (HIV) preexposure prophylaxis (PrEP) is reportedly efficacious, although full trial results have not been published. We used a dynamic network model of HIV transmission among men who have sex with men to assess the population impact of LAI-PrEP when available concurrently with daily-oral (DO) PrEP.MethodsThe reference model represents the current HIV epidemiology and DO-PrEP coverage (15% among those with behavioral indications for PrEP) among men who have sex with men in the southeastern United States. Primary analyses investigated varied PrEP uptake and proportion selecting LAI-PrEP. Secondary analyses evaluated uncertainty in pharmacokinetic efficacy and LAI-PrEP persistence relative to DO-PrEP.ResultsCompared with the reference scenario, if 50% chose LAI-PrEP, 4.3% (95% simulation interval, -7.3% to 14.5%) of infections would be averted over 10 years. The impact of LAI-PrEP is slightly greater than that of the DO-PrEP-only regimen, based on assumptions of higher adherence and partial protection after discontinuation. If the total PrEP initiation rate doubled, 17.1% (95% simulation interval, 6.7%-26.4%) of infections would be averted. The highest population-level impact occurred when LAI-PrEP uptake and persistence improved.ConclusionsIf LAI-PrEP replaces DO-PrEP, its availability will modestly improve the population impact. LAI-PrEP will make a more substantial impact if its availability drives higher total PrEP coverage, or if persistence is greater for LAI-PrEP.
Project description:BackgroundThe human immunodeficiency virus (HIV) epidemic in India is concentrated among 3.1 million men who have sex with men (MSM) and 1.1 million people who inject drugs (PWID), with a mean incidence of 0.9-1.4 per 100 person-years. We examined the cost-effectiveness of both preexposure prophylaxis (PrEP) and HIV testing strategies for MSM and PWID in India.MethodsWe populated an HIV microsimulation model with India-specific data and projected clinical and economic outcomes of 7 strategies for MSM/PWID, including status quo; a 1-time HIV test; routine HIV testing every 3, 6, or 12 months; and PrEP with HIV testing every 3 or 6 months. We used a willingness-to-pay threshold of US$1950, the 2017 Indian per capita gross domestic product, to define cost-effectiveness.ResultsHIV testing alone increased life expectancy by 0.07-0.30 years in MSM; PrEP added approximately 0.90 life-years to status quo. Results were similar in PWID. PrEP with 6-month testing was cost-effective for both MSM (incremental cost-effectiveness ratio [ICER], $1000/year of life saved [YLS]) and PWID (ICER, $500/YLS). Results were most sensitive to HIV incidence. PrEP with 6-month testing would increase HIV-related expenditures by US$708 million (MSM) and US$218 million (PWID) over 5 years compared to status quo.ConclusionsWhile the World Health Organization recommends PrEP with quarterly HIV testing, our analysis identifies PrEP with semiannual testing as the cost-effective HIV prevention strategy for Indian MSM and PWID. Since nationwide scale-up would require a substantial fiscal investment, areas of highest HIV incidence may be the appropriate initial targets for PrEP scale-up.
Project description:BackgroundEfforts to end the human immunodeficiency virus (HIV) epidemic may be threatened if limited preexposure prophylaxis (PrEP) resources are funneled from tenofovir disoproxil fumarate with emtricitabine (TDF/FTC) to tenofovir alafenamide with emtricitabine (TAF/FTC) without proportional clinical benefits.MethodsThe study population was patients at a Boston community health center who were assigned male sex at birth, aged ≥18 years, and prescribed TDF/FTC for PrEP in the 12 months before TAF/FTC approval (October 2019). We determined the frequency of switching to TAF/FTC in the 12 months after approval, including clinically indicated switching (ie, creatinine clearance <60 mL/minute or reduced bone density), potentially unnecessary switching (ie, no indications for switching and no cardiovascular risk factors), and potentially harmful switching (ie, no indications for switching and either obesity or dyslipidemia).ResultsOf 2892 TDF/FTC users, mean age was 38 years, 96.0% were cisgender men, and 78.9% were white. A total of 343 (11.9%) switched to TAF/FTC. Based on documented renal, bone, and cardiovascular risk factors, we identified 24 (7.0%) with clinically indicated switching, 271 (79.0%) with potentially unnecessary switching, and 48 (14.0%) with potentially harmful switching. When indications for switching additionally included hypertension, diabetes, and creatinine clearance 60-70 mL/minute, 27.1% of switching was clinically indicated.ConclusionsFew who switched to TAF/FTC had documented indications for switching, although some appear to have been switched in anticipation of indications developing. As generic TDF/FTC is further discounted, provider education and patient decision aids are needed to facilitate selection of PrEP medications that is both clinically sound and cost-effective.
Project description:BackgroundPreexposure prophylaxis (PrEP) is highly effective for preventing human immunodeficiency virus (HIV) infection, but risk compensation (RC) in men who have sex with men (MSM) raises concerns about increased sexually transmitted infections (STIs). The Center for Disease Control and Prevention's (CDC's) PrEP guidelines recommend biannual STI screening, which may reduce incidence by treating STIs that would otherwise remain undiagnosed. We investigated these two counteracting phenomena.MethodsWith a network-based mathematical model of HIV, Neisseria gonorrhoeae (NG), and Chlamydia trachomatis (CT) transmission dynamics among MSM in the United States, we simulated PrEP uptake following the prescription indications and HIV/STI screening recommendations in the CDC guidelines. Scenarios varied PrEP coverage (the proportion of MSM indicated for PrEP who received it), RC (a reduction in the per-act probability of condom use), and the STI screening interval.ResultsIn our reference scenario (40% coverage, 40% RC), 42% of NG and 40% of CT infections would be averted over the next decade. A doubling of RC would still result in net STI prevention relative to no PrEP. STIs declined because PrEP-related STI screening resulted in a 17% and 16% absolute increase in the treatment of asymptomatic and rectal STIs, respectively. Screening and timely treatment at quarterly vs biannual intervals would reduce STI incidence an additional 50%.ConclusionsImplementation of the CDC PrEP guidelines while scaling up PrEP coverage could result in a significant decline in STI incidence among MSM. Our study highlights the design of PrEP not only as antiretroviral medication but as combination HIV/STI prevention incorporating STI screening.
Project description:BackgroundHuman immunodeficiency virus (HIV) preexposure prophylaxis (PrEP) has helped reduce new HIV infections. However, bacterial sexually transmitted infections (STIs) have increased among PrEP users. We examined PrEP knowledge, access, and risk perceptions in an age of antimicrobial resistance (AMR).MethodsAn online anonymous survey was distributed to all cisgender men/transpersons who have sex with men attending a sexual health clinic in Bristol, United Kingdom (October 2018 to November 2019). Interviews with a sample identified at increased risk of HIV were analyzed thematically and integrated with survey data.ResultsFive hundred and seventy-eight (95%) of 617 cisgender men/transpersons who have sex with men survey respondents were HIV-negative/unknown, of these, 202 (34.9%) had ever used PrEP. Interviewees (n = 24) reported widespread awareness of and enthusiasm for PrEP. Among nonusers, 39% (146/376) were unaware how to access PrEP, and 27% (103/376) could not access PrEP through the national "impact" trial of whom 79% (81/103) were eligible. The PrEP was described as "life-changing," but expense was the main barrier to use. Sixty-two percent (358/578) of HIV-negative/unknown respondents on PrEP were more likely to have condomless anal intercourse with someone they thought was HIV-negative. Interviewees used PrEP with other risk-reduction strategies. Sexually transmitted infections were seen as "curable" and AMR rarely influenced risk perception or sexual decision making.ConclusionsThe PrEP awareness was high, but purchase cost limited access. PrEP may increase condomless anal intercourse, but interviewees used PrEP as one of many risk-reduction tools. Reduced fear of HIV transmission and testing was highly valued. Sexually transmitted infection AMR was not seen as an immediate threat and did not influence risk perception or sexual decision making.
Project description:BACKGROUND:Preexposure prophylaxis (PrEP) greatly reduces the risk of human immunodeficiency virus (HIV) acquisition, but its optimal delivery strategy remains uncertain. Clinics for sexually transmitted infections (STIs) can provide an efficient venue for PrEP delivery. METHODS:To quantify the added value of STI clinic-based PrEP delivery, we used an agent-based simulation of HIV transmission among men who have sex with men (MSM). We simulated the impact of PrEP delivery through STI clinics compared with PrEP delivery in other community-based settings. Our primary outcome was the projected 20-year reduction in HIV incidence among MSM. RESULTS:Assuming PrEP uptake and adherence of 60% each, evaluating STI clinic attendees and delivering PrEP to eligible MSM reduced HIV incidence by 16% [95% uncertainty range, 14%-18%] over 20 years, an impact that was 1.8 (1.7-2.0) times as great as that achieved by evaluating an equal number of MSM recruited from the community. Comparing strategies where an equal number of MSM received PrEP in each strategy (ie, evaluating more individuals for PrEP in the community-based strategy, because MSM attending STI clinics are more likely to be PrEP eligible), the reduction in HIV incidence under the STI clinic-based strategy was 1.3 (1.3-1.4) times as great as that of community-based delivery. CONCLUSIONS:Delivering PrEP to MSM who attend STI clinics can improve efficiency and effectiveness. If high levels of adherence can be achieved in this population, STI clinics may be an important venue for PrEP implementation.
Project description:Preexposure prophylaxis (PrEP) is efficacious in preventing human immunodeficiency virus (HIV) among men who have sex with men (MSM). We assessed PrEP uptake among MSM presenting for services at a sexually transmitted diseases (STD) clinic.Men who have sex with men presenting to the Rhode Island STD Clinic between October 2013 and November 2014 were educated about, and offered, PrEP. We categorized PrEP engagement using an implementation cascade to describe gaps in uptake which described MSM who: (1) were educated about PrEP, (2) indicated interest, (3) successfully received follow-up contact, (4) scheduled an appointment, (5) attended an appointment, and (6) initiated PrEP (ie, received a prescription). Bivariate and multivariable logistic regression models were used to examine predictors of PrEP initiation.A total of 234 MSM were educated about PrEP; of these, 56% expressed interest. Common reasons for lack of interest were low HIV risk perception (37%), wanting more time to consider (10%), concern about side effects (7%), and financial barriers (3%). Among those interested, 53% followed up. Of those, 51% scheduled an appointment. The most common reason patients did not schedule an appointment was low HIV risk perception (38%). Seventy-seven percent of those with an appointment attended the appointment; of those, 93% initiated PrEP. Patients with higher HIV-risk perception (adjusted odds ratios, 2.17; 95% confidence interval, 1.29-3.64) and a history of sex with an HIV-positive partner (adjusted odds ratios, 7.08; 95% confidence interval, 2.35-21.34) had significantly higher odds of initiating PrEP.Low HIV-risk perception was the most significant barrier to PrEP uptake among MSM attending a public STD clinic.
Project description:Background:Adherence is critical for efficacy of tenofovir disoproxil fumarate/emtricitabine (FTC) as preexposure prophylaxis (PrEP). Methods:Between February 2013 and February 2016, 398 men who have sex with men and transgender women were randomized 1:1 to receive individualized texting for adherence building (iTAB) or standard care (SoC) for 48 weeks. The primary endpoint was dried blood spot (DBS) tenofovir diphosphate (TFV-DP) concentrations at both week 12 and the last on-drug visit of >719 fmol/punch (ie, adequate adherence). Secondary outcomes included DBS TFV-DP concentrations of >1246 fmol/punch (ie, near-perfect adherence) and plasma FTC >350 ng/mL (consistent with dosing within the past 24 hours). Results:Concentrations >719 fmol/punch of TFV-DP were found in 88.6% of participants at week 12 and 82.5% at week 48. For the primary endpoint, the study arms did not differ (72.0% in iTAB and 69.2% in SoC; P > .05). For the secondary composite endpoint of >1246 fmol/punch the iTAB arm was superior to SoC (33.5% vs 24.8%; P = .06), reaching statistical significance when adjusting for age (odds ratio, 1.56 [95% confidence interval, 1.00-2.42]; P < .05). At week 48, iTAB was superior to SoC for near-perfect adherence (51.0% vs 37.4%; P = .02). At week 12, iTAB was superior to SoC for dosing in past 24 hours by plasma FTC (47.5% vs 33.3%; P = .007), but not at weeks 24, 36, and 48 (all P > .05). Conclusions:Automated text messaging is a low-burden tool that improves durability of near-perfect PrEP adherence. Clinical Trials Registration:NCT01761643.
Project description:Background:Nondaily dosing of oral preexposure prophylaxis (PrEP) may provide equivalent coverage of sex events compared with daily dosing. Methods:At-risk men and transgender women who have sex with men were randomly assigned to 1 of 3 dosing regimens: 1 tablet daily, 1 tablet twice weekly with a postsex dose (time-driven), or 1 tablet before and after sex (event-driven), and were followed for coverage of sex events with pre- and postsex dosing measured by weekly self-report, drug concentrations, and electronic drug monitoring. Results:From July 2012 to May 2014, 357 participants were randomized. In Bangkok, the coverage of sex events was 85% for the daily arm compared with 84% for the time-driven arm (P = .79) and 74% for the event-driven arm (P = .02). In Harlem, coverage was 66%, 47% (P = .01), and 52% (P = .01) for these groups. In Bangkok, PrEP medication concentrations in blood were consistent with use of ?2 tablets per week in >95% of visits when sex was reported in the prior week, while in Harlem, such medication concentrations occurred in 48.5% in the daily arm, 30.9% in the time-driven arm, and 16.7% in the event-driven arm (P < .0001). Creatinine elevations were more common in the daily arm (P = .050), although they were not dose limiting. Conclusions:Daily dosing recommendations increased coverage and protective drug concentrations in the Harlem cohort, while daily and nondaily regimens led to comparably favorable outcomes in Bangkok, where participants had higher levels of education and employment. Clinical Trials Registration:NCT01327651.