Switching from twice‐daily abacavir and lamivudine to the once‐daily fixed‐dose combination tablet of abacavir and lamivudine improves patient adherence and satisfaction with therapy

Abstract

Patients prefer fewer pills and once-daily (qd) dosing without food restrictions. We assessed the impact on adherence [by Medication Event Monitoring System (MEMS) cap monitoring] of switching from abacavir (ABC) and lamivudine (3TC) twice daily (bid) to ABC/3TC fixed-dose formulation (FDC, Kivexa s ) qd to achieve a qd regimen. MethodsA randomized, open-label, 8-week study comparing adherence, efficacy and safety of immediate vs. delayed switching from ABC/3TC to FDC qd. ResultsNinety-four patients were dosed. Significantly improved adherence was observed at week 4 with qd ABC/3TC across all three adherence variables: taking compliance 99.2% (90.7-100%) vs. 96.6% (60.0-100%) (P 5 0.017); dosing compliance 97.1% (64.3-100%) vs. 91.9% (33.3-100%) (P 5 0.016); and timing compliance 95.5% (53.8-100%) vs. 86.3% (4.3-100%) (P 5 0.006). Treatment satisfaction increased significantly at week 4 with ABC/3TC qd [92% (82-99%) vs. 85% (75-93%) (P 5 0.004)]. Two patients were withdrawn from the study because of intolerance to ABC/3TC. ConclusionsSwitching from ABC and 3TC bid to ABC/3TC FDC qd significantly improved adherence by MEMS cap monitoring at week 4 and improved patient satisfaction with therapy. The results remain to be confirmed over a longer follow-up. Use of qd regimens supports adherence and improves treatment satisfaction relative to bid regimens.Keywords: abacavir, adherence, HIV, lamivudine, once daily, treatment satisfaction IntroductionSignificant improvements have been observed in HIVassociated mortality and morbidity since the introduction of highly active antiretroviral therapy (HAART) [1]. Therapeutic success with any medication is dependent not only on the intrinsic properties of that medication but also on the individual's ability to reliably take the medication. This is particularly true in HIV infection, where the consequence of failing to achieve durable full viral suppression with antiretroviral therapy (ART) is the evolution of resistant virus and a reduction in treatment options [2]. Factors consistently associated with treatment success include the individual's belief systems regarding medication [3], education regarding HIV disease and its management [4], active substance abuse [5] and the social, emotional and financial status of the individual [6]. Factors relating specifically to ART include medication tolerability [7] and regimen characteristics such as the frequency of dosing and the number of pills per intake [8].A systematic review of studies across a range of medical specialties in which adherence was assessed by electronic recording devices indicated that once-daily (qd) therapy improves adherence to therapy relative to more frequent DOI: 10.1111DOI: 10. /j.1468DOI: 10. -1293DOI: 10. .2008 (2008), 9, 667-672 667 dosing, although statistical significance was not demonstrated relative to twice-daily (bid) regimens [9]. A large survey of HIV-positive persons has indicated that they would prefer therapy involving few pills, qd dosing and no food restrictions [10]. An increasing num...

Interventions for Enhancing Adherence to Antiretroviral Therapy (ART): A Systematic Review of High Quality Studies

“…Risk of bias assessments are summarized in Tables 2, 3 83 and one in which we judged the risk of bias to be high because some participants were allocated to the intervention arm without randomization. 82 Allocation concealment.…”

“…39,47,78,79,82 Interventions. Based on the factors responsible for poor adherence, the interventions were categorized as patient related (n = 31), 36 37,62,63,69,83 social and economic factors (n = 1), 77 and condition related (n = 1). 44 The interventions in thirty-nine of these studies targeted only the patient; …”

“…79 The country in which the study was conducted was not reported in five studies. [80][81][82][83][84] The median sample size was 170 (min = 34; max 966).…”

Steady-State Pharmacokinetics of Abacavir in Plasma and Intracellular Carbovir Triphosphate following Administration of Abacavir at 600 Milligrams Once Daily and 300 Milligrams Twice Daily in Human Immunodeficiency Virus-Infected Subjects

“…In conclusion, this study showed that ABC 600 mg QD and ABC 300 mg BID regimens led to similar intracellular CBV-TP C values, thus providing pharmacokinetic support for the interchangeability of these two regimens. Women had higher intracellular CBV-TP exposure than did men.Simplification of antiretroviral treatment (ART) by changing twice-daily (BID) regimens to once-daily (QD) regimens has been shown to contribute to better adherence and patient satisfaction (1,4,5,11,12,15,16), although differences in treatment outcome have not been commonly observed (5, 11). The decision to choose a QD regimen over a BID one, or vice versa, depends on the clinical situation.…”

Issues in resistance, adherence, and comparative efficacy of the single-tablet regimen combination of tenofovir, emtricitabine, and efavirenz in the management of HIV-1 infection

“…82 Switching from two separate NRTIs to combination pills has also shown to improve adherence and patient satisfaction. 83,84 Additionally, patients on NNRTI-based regimens have been shown in the past to have better adherence than those on PI-based regimens, likely at least in part due to the relatively low pill count and simplicity of NNRTI combinations, 85 though this has never been confirmed in a randomized trial. The importance of decreased regimen complexity and pill burden may be most important in those with significant social barriers to care.…”