Tenofovir disoproxil fumarate/emtricitabine plus ritonavir-boosted lopinavir or cobicistat-boosted elvitegravir as a single-tablet regimen for HIV post-exposure prophylaxis

Post-exposure prophylaxis to prevent HIV: new drugs, new approaches, and more questions

Post-exposure prophylaxis (PEP) to prevent HIV acquisition has been recommended for over three decades, but remains underutilised. Over the past decade, clinical trials have established the safety and tolerability of newer PEP regimens, particularly those containing integrase strand transfer inhibitors (INSTIs) combined with a tenofovir and lamivudine or emtricitabine backbone. Several of these regimens were better tolerated than historical controls. Studies in macaques found that shorter courses of PEP with INSTIs were effective, particularly if dosing occurred close to the time of retroviral exposure. Despite the increase in well tolerated options, PEP seems to be underused globally and links to other prevention services are suboptimal. Interventions to increase provider and community awareness of PEP are needed.

Self-start HIV postexposure prophylaxis (PEPSE), to reduce time to first dose and increase efficacy

BACKGROUND

Effectiveness of HIV postexposure prophylaxis (PEPSE) correlates with speed of uptake following HIV exposure. Time to first dose has not improved in the UK for over 10 years. On-demand pre-exposure prophylaxis (PrEP) has shown that people can self-start medication for HIV prevention.We hypothesised that advanced provision of PEPSE (HOME PEPSE) for men who have sex with men (MSM) to self- initiate would reduce time to first dose following HIV exposure.

METHODS

Phase IV, randomised, prospective, 48-week, open-label study was carried out. MSM at medium risk of acquiring HIV were randomised (1:1) to immediate or deferred standard of care (SOC) HOME PEPSE. Every 12 weeks, participants self-completed mental health/risk behaviour surveys and had HIV/sexually transmitted infection (STI) testing.HOME PEPSE comprised a 5-day pack of emtricitabine/tenofovir disoproxil fumarate/maraviroc 600 mg once daily initiated following potential exposure to HIV. If taken, participants completed a risk survey; PEPSE continuation was physician directed. Primary outcome was time from potential exposure to HIV to first PEPSE dose.

FINDINGS

139 participants randomised 1:1; 69 to immediate HOME PEPSE and 70 to deferred HOME PEPSE. Median age 30 years (IQR 26-39), 75% white, 55% UK born and 72% university educated. 31 in HOME PEPSE and 15 in SOC arm initiated PEPSE. Uptake of HOME PEPSE was appropriate in 27/31 cases (87%, 95% CI: 71% to 95%). Median time from exposure to first dose was 7.3 hours (3.0, 20.9) for HOME PEPSE and 28.5 hours (17.3, 34.0) for SOC (p<0.01). HOME PEPSE was well tolerated with no discontinuations.No significant differences in missed opportunities for PEPSE uptake, sexual behaviour or bacterial STI infections between treatment arms.

INTERPRETATION

HOME PEPSE reduced the time from exposure to first-dose PEPSE by 21+ hours, with no impact on safety. This significantly improves the efficacy of PEPSE and provides an option for people declining PrEP.

Doravirine/Lamivudine/Tenofovir Disoproxil Fumarate for Nonoccupational HIV-1 Postexposure Prophylaxis: A Prospective Open-Label Trial (DORAVIPEP)

Background

New regimens may provide better tolerability, convenience, and safety for nonoccupational human immunodeficiency virus (HIV) postexposure prophylaxis (PEP). For this reason, we evaluated the single-tablet regimen of doravirine/lamivudine/tenofovir disoproxil fumarate (DOR/3TC/TDF) for 28 days.

Methods

This was a prospective, open-label, single-arm trial including individuals with potential HIV-1 exposure within 72 hours. The primary endpoint was noncompletion of PEP at day 28. Secondary endpoints were adverse effects, adherence, and rate of seroconversion. We performed follow-up at day 7, week 4, and week 12.

Results

Between September 2019 and March 2022, the study enrolled 399 individuals. Median age was 30 (interquartile range [IQR], 27-36) years, and 91% (n = 364) were male. The mode of exposure was sex between men in 84% (n = 331) of cases; risk assessment for HIV-1 transmission was considered as "high" in 97% (n = 385) of the participants. Median time from exposure to consultation was 24 (IQR, 13-40) hours. Noncompletion of PEP was 29% (n = 114) (95% confidence interval [CI], 24%-33%) and 20% (n = 72) (95% CI, 16%-25%) per modified intention-to-treat. Main reasons for noncompletion were loss to follow-up (n = 104 [91%]) and intolerance (n = 8 [7%]). Older age was associated with a lower risk of premature discontinuation (OR, 0.94; P < .001). One hundred twenty-three (31%) participants reported adverse events, mostly mild and self-limited (82%); discontinuation occurred in 8 cases (2%). Adherence to PEP in the assessed users was 96%. There were no HIV seroconversions.

Conclusions

DOR/3TC/TDF is a well-tolerated option for nonoccupational PEP. Clinical Trials Registration. NCT04233372.

An open-label evaluation of safety and tolerability of coformulated bictegravir/emtricitabine/tenofovir alafenamide for post-exposure prophylaxis following potential exposure to human immunodeficiency virus-1

BACKGROUND

Single-tablet regimen (STR) provides a convenient once-daily regimen for the prevention of human immunodeficiency virus (HIV) infection. Here, we investigated the safety and tolerability of coformulated bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) as a three-drug, STR for post-exposure prophylaxis (PEP) in Chinese individuals.

METHODS

This was a prospective, open-label, single-arm trial conducted in a sexually transmitted diseases and acquired immunodeficiency syndrome clinic of a tertiary hospital in Beijing, China. Adults requiring PEP were prescribed BIC/FTC/TAF one pill once a day for 28 days. Clinical and laboratory data were collected and analyzed at baseline, weeks 2, 4, 8, 12, and 24.

RESULTS

Of 112 participants enrolled in the study, 109 (97.3%) were male and the mean age was 30 ± 8 years. PEP completion was 96.4% (95% confidence interval: 91.1-99.0%). Two participants stopped PEP after 2 days because the source partner was identified as HIV uninfected. One participant was excluded due to hepatitis B virus infection according to the exclusion criteria. One discontinued due to the participant's decision. No participant acquired HIV through week 24. Adherence was 98.9% (standard deviation [SD]: 3.3%) by self-reporting and 98.5% (SD: 3.5%) by pill count. Only five participants experienced mild clinical adverse events attributed to the study drug (including headache, diarrhea, and nausea) and four participants had elevated serum creatinine (grade 1).

CONCLUSIONS

A once daily, STR of BIC/FTC/TAF used as PEP was safe and well-tolerated with a high rate of completion and adherence in Chinese. BIC/FTC/TAF may be a good option for PEP.

TRIAL REGISTRATION

ChiCTR.org.cn, ChiCTR2100048080.

Safety and Tolerability of Once Daily Coformulated Bictegravir, Emtricitabine, and Tenofovir Alafenamide for Postexposure Prophylaxis After Sexual Exposure

BACKGROUND

Antiretroviral post-exposure prophylaxis (PEP) is recommended to prevent HIV infection after a high-risk exposure, but current regimens have presented challenges in tolerability, regimen completion, and potential drug-drug interactions. Because coformulated bictegravir, emtricitabine, and tenofovir alafenamide [BIC/FTC/tenofovir alafenamide (TAF)] is effective for HIV treatment, it was evaluated for use for PEP.

SETTING

Boston community health center.

METHODS

Individuals accessing PEP were enrolled in an open-label study of coformulated BIC/FTC/TAF, taken as one pill daily for 28 days. Pearson's χ2 and Fisher's exact tests were used to assess whether BIC/FTC/TAF differed with respect to side effects and regimen completion rates compared with historical PEP regimens.

RESULTS

Between August, 2018 and March, 2020, 52 individuals enrolled in the study. Most identified as cisgender gay (67.3%) or bisexual (11.5%) men, but 7.7% identified as cisgender heterosexual men and 3.8% cisgender heterosexual women. The most common regimen side effects were nausea or vomiting (15.4%), fatigue (9.6%), and diarrhea/loose stools (7.7%), which were less common than historical controls using other PEP regimens, including those containing other integrase strand transfer inhibitors. Only 1 participant discontinued the regimen because of fatigue, and all other side effects were self-limited. Almost all participants (90.4%) completed the indicated regimen, which was a higher completion rate compared with earlier PEP regimens, and none became HIV-positive.

CONCLUSIONS

BIC/FTC/TAF coformulated as a single daily pill was found to be safe, well-tolerated, and highly acceptable when used for PEP, and compared more favorably than historical PEP regimens used at an urban health center.

UK guideline for the use of HIV post-exposure prophylaxis 2021

We present the updated British Association for Sexual Health and HIV (BASHH) guidelines for post-exposure prophylaxis (PEP) to HIV following sexual exposures, occupational exposures and other nonoccupational exposures in the community. This serves as an update to the 2015 BASHH guideline on PEP following sexual exposures and the 2008 Expert Advisory Group on AIDS guidelines on HIV PEP. We aim to provide evidence-based guidance on best clinical practice in the provision, monitoring and support of PEP for the prevention of HIV acquisition following sexual, occupational and other nonoccupational exposures in the community. The guideline covers when to prescribe PEP, what antiretroviral agents to use and how to manage PEP. This includes (i) evidence of PEP efficacy; (ii) evidence relating to individual-level efficacy of antiretroviral therapy to prevent the sexual transmission of HIV; (iii) data on the detectable (transmissible) prevalence of HIV in specific populations; (iv) risk of HIV transmission following different types of sexual and occupational exposure; (v) baseline risk assessment; (vi) drug regimens and dosing schedules; (vii) monitoring PEP; (viii) baseline and follow-up blood-borne virus testing; (ix) the role of PEP within broader HIV prevention strategies, for example, HIV pre-exposure prophylaxis (PrEP). The guideline also covers special scenarios such as PEP in pregnancy, breastfeeding and chronic hepatitis B virus infection, and when PEP should be considered in people using HIV PrEP. The guidelines are aimed at clinical professionals directly involved in PEP provision and other stakeholders in the field. A proforma to assist PEP consultations is included. A public consultation process was undertaken prior to finalizing the recommendations.

Tolerability and Adherence of Antiretroviral Regimens Containing Long-Acting Fusion Inhibitor Albuvirtide for HIV Post-Exposure Prophylaxis: A Cohort Study in China

INTRODUCTION

There have been no prospective clinical studies investigating adherence and tolerability of HIV post-exposure prophylaxis (PEP) in China. Tolerability, adherence, and transmitted drug resistance are concerns, especially when single-tablet regimen (STR) usage is low. The present study aimed to explore the safety, tolerability, and adherence of regimens containing albuvirtide (ABT) compared with recommended non-STR antiretrovirals for HIV PEP.

METHODS

This was a prospective, open-label, multicenter cohort study. The subjects were stratified into 3 groups based on their preference: ABT + Dolutegravir (DTG) (Group 1), ABT + Tenofovir disoproxil fumarate (TDF) + Lamivudine (3TC) (Group 2), and DTG + TDF + 3TC (Group 3). All enrolled subjects received PEP within 72 h after exposure and continued for 28 days, and were followed-up for 12 weeks.

RESULTS

A total of 330 participants were enrolled in the three groups. Most participants were male (87.2%). Sexual contact was the most frequent mode of exposure (91.9%). The average time from exposure to treatment was 26.8 ± 19.5 h. There were no statistically significant differences between the three study groups with respect to completion of oral medication at 28 days. The 28-day completion rate was shown to be significantly higher with ABT versus oral (88.9% vs. 64.0%; p < 0.0001), and adherence with ABT was 94.4% compared to 75.7% with oral PEP (p < 0.0001). Subjects in ABT-containing Group 1 exhibited higher adherence than those in Group 3 (87.3% vs. 72.9%; p < 0.05). None of the participants reported serious adverse drug reactions which led to withdrawal from the study. All the drug regimens were found to be safe and well tolerated. No HIV incident case was observed during the study period.

CONCLUSIONS

ABT-containing regimens (ABT + DTG or ABT + TDF + 3TC) offer a good option for HIV PEP due to higher completion rates and adherence than the DTG + TDF + 3TC regimen. The overall safety was comparable and acceptable among the three groups.

REGISTRATION

The study was registered in Chinese Clinical Trial Registry with registration number (ChiCTR1900022881, http://www.chictr.org.cn/showprojen.aspx?proj=37395 ).

Elvitegravir-Cobicistat-Emtricitabine-Tenofovir Alafenamide Single-tablet Regimen for Human Immunodeficiency Virus Postexposure Prophylaxis

We evaluated an elvitegravir-cobicistat-emtricitabine-tenofovir alafenamide single-tablet regimen for human immunodeficiency virus postexposure prophylaxis. The completion rate and adherence were good, and the tolerance was acceptable; no seroconversion was observed. We confirm that this regimen could be appropriate for postexposure prophylaxis.

CLINICAL TRIALS REGISTRATION

NCT02998320.

Network meta-analysis of post-exposure prophylaxis randomized clinical trials

OBJECTIVES

We performed a network meta-analysis of PEP randomized clinical trials to evaluate the best regimen.

METHODS

After MEDLINE/Pubmed search, studies were included if: (1) were randomized, (2) comparing at least 2 PEP three-drug regimens and, (3) reported completion rates or discontinuation at 28 days. Five studies with 1105 PEP initiations were included and compared ritonavir-boosted lopinavir (LPV/r) vs. atazanavir (ATV) (one study), cobicistat-boosted elvitegravir (EVG/c) (one study), raltegravir (RAL) (one study) or maraviroc (MVC) (two studies). We estimated the probability of each treatment of being the best based on the evaluation of five outcomes: PEP non-completion at day 28, PEP discontinuation due to adverse events, PEP switching due to any cause, lost to follow-up and adverse events.

RESULTS

Participants were mostly men who have sex with men (n = 832, 75%) with non-occupational exposure to HIV (89.86%). Four-hundred fifty-four (41%) participants failed to complete their PEP course for any reason. The Odds Ratio (OR) for PEP non-completion at day 28 in each antiretroviral compared to LPV/r was: ATV 0.95 (95% CI 0.58-1.56; EVG/c: OR 0.65 95% CI 0.30-1.37; RAL: OR 0.68 95% CI 0.41-1.13; and MVC: OR 0.69 95% CI 0.47-1.01. In addition, the rankogram showed that EVG/c had the highest probability of being the best treatment for the lowest rates in PEP non-completion at day 28, switching, lost to follow-up or adverse events and MVC for PEP discontinuations due to adverse events.

CONCLUSIONS

Our study shows the advantages of integrase inhibitors when used as PEP, particularly EVG as a Single-Tablet Regimen.

Single-tablet regimen of emtricitabine/tenofovir disoproxil fumarate plus cobicistat-boosted elvitegravir increase adherence for HIV postexposure prophylaxis in sexual assault victims

BACKGROUND

Postexposure prophylaxis (PEP) is a recommended public health intervention after a sexual assault to prevent HIV infection.

METHODS

We conducted a retrospective case-control study on how use of a single-tablet regimen (STR) of elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (Stribild) affected adherence to PEP and attendance of a follow-up visit to the STI clinic compared with those who received a multitablet regimen (MTR). Data from sexual assault victims consulting for PEP were prospectively recorded between January 2011 and December 2017. Data were systematically collected on patient demographics, time of medical contact, source risk factors, type of exposure, attendance to follow-up visit, reported completion of PEP and adherence based on pharmacy records.

RESULTS

A total of 422 patients received PEP following a sexual assault, of whom 52% had documented completion of a 28-day PEP regimen and 71% attended a follow-up clinic visit. Patients who received an elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (EVG/COBI/FTC/TDF)-based STR had a similar likelihood of attending their first follow-up visit (OR: 0.97; 95% CI: 0.64 to 1.48, p=0.90) but were more likely to complete the PEP regimen (OR: 1.70; 95% CI: 1.16 to 2.50, p=0.007). After adjusting for confounders, those who were prescribed an STR regimen were more likely to complete the PEP regimen (OR: 1.66, 95% CI: 1.09 to 2.53, p=0.019) than those who were prescribed an MTR such as stavudine/lamivudine/lopinavir/ritonavir or zidovudine/lamivudine/indinavir/ritonavir.

CONCLUSIONS

Sexual assault victims who were prescribed an STR based on EVG/COBI/FTC/TDF were more likely to complete PEP than those who were prescribed an MTR.

Post-exposure prophylaxis completion and condom use in the context of potential sexual exposure to HIV

OBJECTIVES

Post-exposure prophylaxis (PEP) care remains a challenge for individuals with potential sexual exposure to HIV in terms of PEP completion and ongoing risk behaviours.

METHODS

A retrospective analysis was carried out on data from the French Dat'AIDS prevention cohort (NCT03795376) for individuals evaluated for PEP between 2004 and 2017. A multivariable analysis was performed of predictors of both PEP completion and condom use [odds ratios (ORs)] and their associated probabilities (P, with P > 95% being clinically relevant).

RESULTS

Overall, 29 060 sexual exposures to HIV were evaluated for PEP [36% in men who have sex with men (MSM) and 64% in heterosexuals]. Overall, 12 different PEP regimens were offered in 19 240 cases (46%). Tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) was the preferred backbone (n = 14 304; 74%). We observed a shift from boosted protease inhibitor-based regimens to nonnucleoside reverse transcriptase inhibitor- or integrase inhibitor-based regimens in recent years. Overall, 20% of PEP prescriptions were prematurely discontinued. Older age, MSM, intercourse with a sex worker, rape and intercourse with a known HIV-infected source patient were factors associated with increased rates of PEP completion (OR > 1; P > 98%). None of the 12 PEP regimens was associated with premature discontinuation. We also found 12 774 cases of unprotected sexual intercourse (48%). Condom use decreased (OR < 1; P > 99%) with the year of exposure, and was lower in MSM and rape victims. Condom use increased (OR > 1, P > 99%) with age, and was higher in those who had intercourse with a sex worker or with a female partner and in those with knowledge of the partner's HIV status.

CONCLUSIONS

We provide new insights into how rates of condom use and PEP completion might be improved in those receiving PEP by targeting certain groups of individuals for interventions. In particular, youth and MSM at risk should be linked in a prevention-to-care continuum.