Asian participants' experience in phase 3/3b studies of long-acting cabotegravir and rilpivirine: Efficacy, safety, pharmacokinetic, and virological outcomes through week 96.

OBJECTIVES: Cabotegravir + rilpivirine (CAB + RPV) dosed monthly or every 2 months is the first complete long-acting (LA) regimen recommended by treatment guidelines for the maintenance of HIV-1 virological suppression. This post hoc analysis summarizes outcomes for Asian participants through week 96. METHODS: Data from Asian participants naive to CAB + RPV randomized to receive dosing every 4 weeks (Q4W) or every 8 weeks (Q8W) in the FLAIR (NCT02938520) and ATLAS-2M (NCT03299049) phase 3/3b studies were pooled. The proportion of participants with plasma HIV-1 RNA ≥50 and <50 copies/mL (per FDA Snapshot algorithm), incidence of confirmed virological failure (CVF; two consecutive HIV-1 RNA ≥200 copies/mL), pharmacokinetics, safety, and tolerability through week 96 were assessed. RESULTS: Overall, 41 Asian participants received CAB + RPV (Q8W, n = 17; Q4W, n = 24). At week 96, 83% (n = 34/41) of participants maintained HIV-1 RNA <50 copies/mL, none had HIV-1 RNA ≥50 copies/mL, and 17% (n = 7/41) had no virological data. No Asian participant met the CVF criterion. Drug-related adverse events occurred in 44% (n = 18/41) of participants; none were Grade ≥3. All injection site reactions were Grade 1 or 2; median duration was 2 days and most resolved within 7 days (90%, n = 390/435). CAB and RPV trough concentrations remained well above their respective protein-adjusted 90% inhibitory concentrations (CAB, 0.166 µg/mL; RPV, 12 ng/mL) through week 96. CONCLUSIONS: CAB + RPV LA demonstrated high efficacy, with no participants having CVF, and an acceptable safety profile in Asian participants through week 96. These data support CAB + RPV LA as a complete regimen for the maintenance of HIV-1 virological suppression in Asian individuals.

Efficacy, safety, and pharmacokinetics by BMI category in Phase 3/3b cabotegravir + rilpivirine long-acting trials.

BACKGROUND: Cabotegravir + rilpivirine (CAB + RPV) is a guideline-recommended long-acting (LA) injectable regimen for the maintenance of HIV-1 virologic suppression. This post hoc analysis summarizes CAB + RPV LA results by baseline body mass index (BMI) category among Phase 3/3b trial participants. METHODS: Data from CAB + RPV-naive participants receiving every 4 or 8 week dosing in FLAIR, ATLAS, and ATLAS-2 M were pooled through Week (W) 48. Data beyond W48 were summarized by study (FLAIR through W96 and ATLAS-2 M through W152). HIV 1 RNA <50 and ≥50 copies/mL, confirmed virologic failure (CVF; two consecutive HIV-1 RNA ≥200 copies/mL), safety and tolerability, and plasma CAB and RPV trough concentrations were evaluated by baseline BMI (<30 kg/m2 [lower]; ≥ 30 kg/m2 [higher]). RESULTS: Among 1245 CAB + RPV LA participants, 213 (17%) had a baseline BMI ≥30 kg/m2. At W48, 92% vs. 93% of participants with lower vs. higher BMI had HIV-1 RNA <50 copies/mL, respectively. Including data beyond W48, 18 participants had CVF; those in the higher BMI group (n = 8) all had at least one other baseline factor associated with CVF (archived RPV resistance-associated mutations or HIV 1 subtype A6/A1). Safety and pharmacokinetic profiles were comparable between BMI categories. CONCLUSION: CAB + RPV LA was efficacious and well tolerated, regardless of baseline BMI category.Main point summary: CAB + RPV LA is effective in the maintenance of HIV-1 virologic suppression in adults regardless of BMI category, with longer-length needles (≥2 inches) recommend for those with BMI ≥30 kg/m2 to accommodate individual body habitus and ensure appropriate administration.

Pregnancy outcomes and pharmacokinetics in pregnant women living with HIV exposed to long-acting cabotegravir and rilpivirine in clinical trials.

BACKGROUND: Limited data exist on pregnant women living with HIV exposed to cabotegravir + rilpivirine (CAB + RPV). Outcomes in pregnant participants exposed to CAB + RPV, and pharmacokinetic washout data in those exposed to CAB + RPV long-acting (LA) with live births, are presented. METHODS: Women exposed to one or more doses of CAB + RPV (oral/LA) from ViiV Healthcare-sponsored phase 2b/3/3b clinical trials and the compassionate use programme who became pregnant were included. Upon pregnancy in the trial programme, CAB + RPV was discontinued, an alternative antiretroviral regimen was initiated, and quarterly pharmacokinetic sampling for 52 weeks post-last injection was obtained. CAB + RPV continuation or alternative antiretroviral regimen initiation was decided by pregnant compassionate use programme participants and their treating physicians. RESULTS: As of 31 March 2021, 25 pregnancies following CAB + RPV exposure at conception were reported (five oral, 20 LA), including four who conceived during pharmacokinetic washout following treatment discontinuation. There were eight elective abortions, six miscarriages (five in first trimester), one ectopic pregnancy, and 10 live births (one oral, nine LA), including one infant born with congenital ptosis. Among participants exposed to CAB + RPV LA at conception with live births, plasma CAB and RPV washout concentrations during pregnancy were within the range of those observed in non-pregnant women. CONCLUSION: In this first analysis of pregnancy outcomes following CAB + RPV exposure at conception, 10 live births, including one with congenital anomaly, were reported. Plasma CAB and RPV washout concentrations during pregnancy were within the range of those in non-pregnant women. Pregnancy surveillance within ViiV Healthcare-sponsored clinical trials is ongoing, with dedicated pregnancy studies planned.

Week 96 Genotypic and Phenotypic Results of the Fostemsavir Phase 3 BRIGHTE Study in Heavily Treatment-Experienced Adults Living with Multidrug-Resistant HIV-1.

In the phase 3 BRIGHTE study in heavily treatment-experienced adults with multidrug-resistant HIV-1, fostemsavir plus optimized background therapy (OBT) resulted in sustained rates of virologic suppression through 96 weeks. HIV-1 RNA <40 copies/mL was achieved in 163/272 (60%) Randomized Cohort (RC) participants (with 1 or 2 remaining approved fully active antiretrovirals) and 37/99 (37%) Non-randomized Cohort (NRC) participants (with 0 fully active antiretrovirals). Here we report genotypic and phenotypic analyses of HIV-1 samples from 63/272 (23%) RC participants and 49/99 (49%) NRC participants who met protocol-defined virologic failure (PDVF) criteria through Week 96. The incidence of PDVF was as expected in this difficult-to-treat patient population and, among RC participants, was comparable regardless of the presence of predefined gp120 amino acid substitutions that potentially influence phenotypic susceptibility to temsavir (S375H/I/M/N/T, M426L, M434I, M475I) or baseline temsavir 50% inhibitory concentration fold change (IC50 FC). The incidence of PDVF was lower among participants with higher overall susceptibility score to newly used antiretrovirals (OSS-new), indicating that OSS-new may be a preferred predictor of virologic outcome in heavily treatment-experienced individuals. Predefined gp120 substitutions, most commonly M426L or S375N, were emergent on treatment in 24/50 (48%) RC and 33/44 (75%) NRC participants with PDVF, with related increases in temsavir IC50 FC. In BRIGHTE, PDVF was not consistently associated with treatment-emergent genotypic or phenotypic changes in susceptibility to temsavir or to antiretrovirals in the initial OBT. Further research will be needed to identify which factors are most likely to contribute to virologic failure in this heavily treatment-experienced population (ClinicalTrials.gov, NCT02362503).

Cabotegravir + Rilpivirine Long-Acting: Overview of Injection Guidance, Injection Site Reactions, and Best Practices for Intramuscular Injection Administration.

Background: Cabotegravir (CAB) + rilpivirine (RPV) dosed monthly or every 2 months is a complete long-acting (LA) regimen for the maintenance of human immunodeficiency virus type 1 virologic suppression. Across the phase 3/3b trials, the most frequently reported adverse events were injection site reactions (ISRs). Methods: We present pooled ISR characteristics and outcomes for participants receiving CAB + RPV LA through week 96 of the FLAIR and ATLAS-2M studies, and survey results from healthcare providers (HCPs) giving injections (eg, injectors) in the ATLAS, FLAIR, and ATLAS-2M studies to determine optimal injection techniques. Surveys were anonymous, self-administered online questionnaires that queried provider demographics, injection experience, and techniques to minimize pre-/postinjection discomfort. Data were summarized using descriptive statistics. Results: Overall, 8453 ISRs were reported by 801 participants receiving ≥1 injection of CAB LA/RPV LA. Most ISRs were mild to moderate in severity (grade 1-2, 99%), with a median duration of 3 days (interquartile range, 2-4 days), and rarely led to withdrawal (2%). Surveys were completed by 181 HCPs across 113 sites. Pushing the intramuscular injection at slow speed (66%), bringing the medication to room temperature (58%), and relaxing the gluteus muscle before injecting (53%) were ranked as effective preinjection/injection procedure practices for minimizing pain. Most injectors (60%) indicated that a prone position provided optimal patient comfort, and 41% had no preference on injection medication order. Conclusions: Taken together, the data demonstrate favorable tolerability with CAB + RPV LA injections over the long term and simple techniques routinely used by injectors to help optimize the administration of CAB + RPV LA injections.