Self‐reported adherence supports patient preference for the single tablet regimen (STR) in the current cART era

In: Journal of the International AIDS Society, Volume 15, Issue S4

Abstract

ObjectiveTo analyze self‐reported adherence to antiretroviral regimens containing ritonavir‐boosted protease inhibitors, non‐nucleoside reverse transcriptase inhibitors (NNRTI), raltegravir, and maraviroc.MethodsOverall, 372 consecutive subjects attending a reference center for HIV treatment in Florence, Italy, were enrolled in the study, from December 2010 to January 2012 (mean age 48 years). A self‐report questionnaire was filled in. Patients were defined as "non‐adherent" if reporting one of the following criteria:<90% of pills taken in the last month, ≥1 missed dose in the last week, spontaneous treatment interruptions reported, or refill problems in the last 3 months. Gender, age, CD4, HIV‐RNA, years of therapy, and type of antiretroviral regimen were analyzed with respect to adherence.ResultsAt the time of the questionnaire, 89.8% of patients had <50 copies/mL HIV‐RNA and 14.2% were on their first combined antiretroviral therapy. 57% of patients were prescribed a regimen containing ritonavir boosted protease inhibitors (boosted PI), 41.7% NNRTI, 17.2% raltegravir, and 4.8% maraviroc; 49.5% of the subjects were on bis‐in‐die regimens, while 50.5% were on once‐daily regimens, with 23.1% of these on the single tablet regimen (STR): tenofovir/emtricitabine/efavirenz. The non‐adherence proportion was lower in NNRTI than in boosted‐PI treatments (19.4% vs 30.2%), and even lower in STR patients (17.4%). In multivariable logistic regression, patients with the NNRTI regimen (OR: 0.56, 95% CI: 0.34–0.94) and the STR (OR: 0.45, 95% CI: 0.22–0.92) reported lower non‐adherence. Efavirenz regimens were also associated with lower non‐adherence (OR: 0.42, 95% CI: 0.21–0.83), while atazanavir/ritonavir regimens were associated with higher non‐adherence. No other relation to specific antiretroviral drugs was found. A higher CD4 count, lower HIV‐RNA, and older age were also found to be associated with lower non‐adherence, while a longer time on combined antiretroviral therapy was related to higher non‐adherence.ConclusionIn conclusion, older age, higher CD4 cell counts, lower HIV‐RNA viral loads, and the use of STR are all related to lower non‐adherence. In particular, the use of STR maintains an advantage in improving adherence with respect to other cARTs, even with the availability of new, well‐tolerated antiretroviral drugs and drug classes in recent years.