OBJECTIVES

Previous real-world studies have shown (1) reduced adherence with more complex, multi-tablet regimens (MTR) relative to simple, single-tablet regimens (STR) and (2) reduced virologic control with decreased regimen adherence. This study evaluated adherence and virologic suppression with second-generation integrase inhibitors (INSTIs) bictegravir (BIC) and dolutegravir (DTG) in patients with HIV.

METHODS

EMR, prescription and dispensing data for 2,217 patients initiating STR BIC/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) or DTG/abacavir/lamivudine (DTG/ABC/3TC) or MTR DTG + tenofovir disoproxil fumarate/emtricitabine (DTG+TDF/FTC) or DTG+TAF/FTC between August 2013 - August 2019 were collected from 5 US practices. Adherence was defined as proportion of days covered (PDC) at 6 months. To determine treatment effects on adherence, we used (1) multiple imputation with predictive posterior matching for missing baseline measures, (2) mixed effects logistic regression to adjust for source heterogeneity, and (3) propensity score matching (PSM) using imputed baseline labs and demographics, allowing for squares and first order interactions between all included predictors. In addition to adherence, we assessed viral suppression (<200 copies/mL) in a subset of 655 patients at 6 months (-1 week to + 2 months).

RESULTS

In observed data, 80% PDC was significantly higher (p<0.01) with STR BIC/FTC/TAF compared to any dolutegravir-regimen and with STR DTG/ABC/3TC in comparison to MTR DTG+TDF/FTC or DTG+TAF/FTC (p<0.01). After PSM, adherence was only significantly different with STR BIC/FTC/TAF compared to MTR DTG+TDF/FTC or DTG+TAF/FTC (p<0.01). Viral suppression at 6 months for patients with measures (n=655) was favorably impacted by PDC ≥80% (OR 2.27 [1.26-4.07] p<0.01).

CONCLUSIONS

Consistent with studies of legacy regimens, these data suggest that simplifying 2^nd generation INSTI-containing regimens to a single tablet aids in adherence and greater adherence improves virologic outcomes.