Physicians' opinions on generic antiretroviral drugs and single-tablet regimen de-simplification for the treatment of HIV infection: a multicentre survey in Spain

Adverse drug reactions attributed to generic substitution of antiretroviral medications among HIV treatment and pre-exposure prophylaxis clients in British Columbia, Canada

BACKGROUND

In British Columbia, antiretrovirals (ARVs) for HIV treatment (HIV-Tx) and pre-exposure prophylaxis (PrEP) are free-of-charge through publicly-funded Drug Treatment Programs (DTPs). When available, less costly generics are substituted for brand-name ARVs. We describe the incidence and type of product substitution issue (PSI) adverse drug reactions (ADRs) attributed to generic ARVs.

METHODS

Cohorts included DTP clients ≥19 years who received generic ARVs for HIV-Tx (abacavir-lamivudine, emtricitabine-tenofovir DF, efavirenz-emtricitabine-tenofovir DF, atazanavir or darunavir between 01 Jun 2017 and 30 Jun 2022) or PrEP (emtricitabine-tenofovir DF, 01 Apr 2018 to 30 Jun 2022). Demographic, ARV and ADR data were extracted from DTP databases and summarized by descriptive statistics. PSI incidence was calculated for each product during the year following brand-to-generic and generic-to-generic transitions (first-year-post-rollout), and compared between generic versions using generalized estimating equations. For context, incidence of any ARV product-related ADR was calculated in the same 1-year periods.

RESULTS

During first-year-post-rollout periods, 5339 HIV-Tx (83% male, median age 52 years) and 8095 PrEP (99% male, median 33 years) clients received generic ARVs, and reported 78 and 23 generic PSIs, respectively. PSI incidence was <1% for most generic ARVs, with mild-moderate symptoms including gastrointestinal upset, headache, dizziness, fatigue/malaise and skin rash. In HIV-Tx clients, the efavirenz-containing product had higher PSI incidence than other ARVs (2.2%, p = .004), due to more neuropsychiatric adverse reactions. Any ADR incidence was stable across measurement periods, and generic PSIs represented less than one third of all product-related ADRs.

CONCLUSIONS

Generic substitution of antiretrovirals for HIV-Tx and PrEP was well tolerated, with ≤2% incidence of mild-moderate PSI ADRs.

Effectiveness and tolerability of dolutegravir and abacavir/lamivudine administered as two separate pills compared to their equivalent single-tablet regimen in a multicentre cohort in Spain

INTRODUCTION

We aimed to assess the effectiveness and tolerability of dolutegravir (DTG), abacavir (ABC) and lamivudine (3TC) administered as branded STR (DTG/ABC/3TC) or as two separate pills (DTG and either branded ABC/3TC [DTG+(ABC/3TC)b] or generic ABC/3TC [DTG+(ABC/3TC)g]).

METHODS

We included individuals from the multicentre cohort of the Spanish HIV/AIDS Research Network (CoRIS) who received DTG/ABC/3TC, DTG+(ABC/3TC)b or DTG+(ABC/3TC)g during 2015 to 2018. We used multivariable logistic regression to compare the proportion of antiretroviral-naïve individuals who achieved viral suppression (VS) (viral load ≤50 copies/mL) at 24 weeks of initiating with DTG+(ABC/3TC)b or DTG+(ABC/3TC)g versus DTG/ABC/3TC. We also calculated the proportion of virologically suppressed individuals who maintained VS at 24 weeks after switching from DTG/ABC/3TC to DTG+(ABC/3TC)g.

RESULTS

During the study period, 829, 68 and 47 treatment-naïve individuals started treatment with DTG/ABC/3TC, DTG+(ABC/3TC)b or DTG+(ABC/3TC)g respectively. The proportions of individuals who changed their regimens due to side effects during the first 24 weeks were 3.7%, 4.4% and 6.4% respectively (p = 0.646). We did not find significant differences in VS at 24 weeks among individuals starting with DTG+(ABC/3TC)b or DTG+(ABC/3TC)g compared to those initiating with DTG/ABC/3TC. Among 177 virologically suppressed individuals who switched from DTG/ABC/3TC to DTG+(ABC/3TC)g, 170 (96.0%) maintained VS at 24 weeks.

CONCLUSIONS

In naïve individuals, the effectiveness and tolerability at 24 weeks of DTG plus ABC/3TC administered as two separate pills, either as branded or generic ABC/3TC, was similar to the STR DTG/ABC/3TC. Switching the STR DTG/ABC/3TC to its separate components DTG+(ABC/3TC)g in virologically suppressed individuals did not seem to impair its effectiveness.

De-simplifying single-tablet antiretroviral treatments for cost savings in France: From the patient perspectives to a 6-month follow-up on generics

In developed countries, most people living with HIV/AIDS are treated with costly brand single-tablet regimens. Given the economic impact, French guidelines recommend using generic antiretroviral therapy when possible to decrease antiretroviral therapy costs. We aimed to study HIV-infected patients’ acceptability to switch from a brand single-tablet regimens [abacavir/lamivudine/dolutegravir (Triumeq^®) or emtricitabine/tenofovir disoproxil fumarate/rilpivirine (Eviplera^®)] to a treatment comprising of two pills: one is a fixed-dose generic combination of 2 Nucleoside Analogs and the second tablet is the third antiretroviral. This study was a prospective observational study in a French hospital. During their follow-up, patients on stable single-tablet regimens were made aware of the possible cost-saving. They were questioned about their willingness and barriers accepting the substitution. Participants chose between the two regimens, either to remain on single-tablet regimens or switch to the de-simplified regimen. Six months later, a second survey was given to the patient who chose to de-simplify and HIV viral load was controlled. The study included 98 patients: 60 receiving emtricitabine/tenofovir disoproxil fumarate/rilpivirine (Eviplera^®) and 38 on abacavir/lamivudine/dolutegravir (Triumeq^®). Forty-five patients accepted the de-simplified treatment, 37 refused and 16 were undecided and followed the decision offered by their physician. The main reason for unwillingness to switch is the number of pills (77.3%). In multivariate model analysis, male patients (p = 0.001) who have taken antiretroviral therapy for over 20 years (p = 0.04) and who retrieve their treatment in their community hospital (p = 0.03) are more likely to accept the switch. Fifty-one patients accepted to replace their single-tablet regimens and six months later, the majority was satisfied; only four returned to single-tablet regimens because of suspected side effects. Half of the people living with HIV/AIDS in our cohort accepted to switch from brand single-tablet regimens to a two-tablet regimen containing generic drugs within a process that emphasizes health expenditure savings.