Clinical outcomes during CUSTOMIZE: a hybrid III implementation-effectiveness study focused on implementation of cabotegravir plus rilpivirine (CAB+RPV) LA in US healthcare settings

BACKGROUND: CUSTOMIZE is an implementation-effectiveness study designed to evaluate implementation of cabotegravir+rilpivirine long-acting (CAB+RPV LA) for HIV treatment in diverse US healthcare settings and populations. This abstract reports the key clinical (secondary) endpoints.
METHODS: This single-arm study enrolled virologically-suppressed people living with HIV infection to receive monthly CAB+RPV LA at 8 US clinics, representing diverse geography including the Southeastern USA. Adverse events were documented monthly; viral load and lab assessments were collected at Months 1, 2, 4, 6, 9, 12. Clinics recorded total time spent in clinic from patient check-in to departures at Months 1, 5, 11.
RESULTS: 115 participants were enrolled, 109 received at least one CAB+RPV LA injection, and 102 completed Month 12; 6 withdrew prior to any injections. Participants were 87% male, 57% Caucasian, 37% Black, 26% Hispanic/Latinx. Mean age was 38.8 years and mean BMI 28.1. Among those with viral load data at Month 12 (n=102), 100% maintained viral suppression (<50 copies/mL); there were no virologic failures. Overall, 95% (1076/1140) of injection visits were completed in the appropriate treatment window (+/-) 7 days from the target treatment date. Five participants missed visits due to COVID-19; all received oral therapy to maintain continuous ART. Majority of adverse events (AEs) were injection site reactions (ISRs). Most ISRs were mild (Grade 1, 78%) or moderate (Grade 2, 18%) and most were reported as pain (69%). Two (2%) participants withdrew due to ISRs. Median total time spent in clinic at Month 1 (first injection visit) was 57 min (IQR: 47-70). Subsequent visits (injection-only visits) were shorter: median duration was 35 min (IQR: 24-48) at Month 5 and 34 min (IQR: 27-44) at Month 11.
CONCLUSIONS: In CUSTOMIZE, a study focused on implementation of LA antivirals in a variety of US healthcare settings, CAB+RPV LA was a highly effective HIV treatment in a diverse population. Many patients reported ISRs but few led to discontinuations. The few COVID disruptions were managed with temporary oral therapy, most participants received injections within the treatment window, time spent in clinic decreased over time, and 100% of participants reaching Month 12 maintained viral load suppression.