Efficacy and safety of abacavir/lamivudine plus rilpivirine as a first-line regimen in treatment-naïve HIV-1 infected adults

Abstract

Background: The anti-retroviral combination of abacavir/lamivudine plus rilpivirine (ABC/3TC/RPV) is not recommended by international guidelines as the first-line regimen. However, it is potent, well-tolerated, and affordable, especially in resource-limited settings. This study evaluates the efficacy and safety of ABC/3TC/RPV as an initial regimen for treatment-naïve HIV-1 infected patients. Methods: A retrospective study was conducted in the largest HIV care centre in Singapore, with data collected June 2011 to September 2017. All treatment-naïve HIV-1 infected adults prescribed ABC/3TC as part of their initial antiretroviral therapy regimen were included. The third drug was a non-nucleoside reverse-transcriptase inhibitor (NNRTI) such as RPV or efavirenz (EFV), or boosted protease-inhibitor (PI). Patients were followed up for 48 weeks. The primary end-point was the percentage of patients achieving virologic suppression, analysed using on-treatment analysis. Secondary outcomes included CD4-count change, treatment discontinuation and treatment-related adverse events. Results: 170 patients were included in the study, 66 patients in the RPV group, 104 patients in the comparator group (EFV or boosted PI). 96% (n = 24) in the RPV group and 87% (n = 26) in the comparator group achieved viral suppression at 48 weeks (p = 0.28). Median (interquartile range) time to viral suppression was similar: 17 (14-24) weeks in the RPV group, and 21 (13-26) weeks in the comparator group. There were no statistically significant differences in the CD4 count between the two groups. 14% (n = 9) of patients on RPV discontinued treatment before 48 weeks, compared to 30% (n = 31) from the comparator group (p = 0.053). Of these, 23 discontinuations were due to drug adverse effects, and only 1 attributed to RPV (p < 0.01). One patient in each group had virologic failure. Conclusion: RPV is effective, safe and considerably more tolerable than compared to NNRTI or boosted PI in ABC/3TC-containing regimens for treatment-naïve patients. It offers an affordable and attractive option, especially in resource-limited settings.

Safety and Effectiveness of Switching to Abacavir/Lamivudine Plus Rilpivirine for Maintenance Therapy in Virologically Suppressed HIV-1 Patients in Singapore (SEALS)

“…AEs were observed amongst 31/222 patients (14.0%) and resolved either spontaneously or upon discontinuation of the medication. These results were comparable to the favourable results of SIMRIKI study, 10 as well as the local study on treatment-naïve HIV-infected patients, 14 which reported only 15.6% and 13.5% of patients with observed AEs respectively. The AE pro le seen in our study was also very similar to the local study which saw mostly neuropsychiatric AEs at a rate of 46.4% of all observed AEs compared to our study which saw 57.1% of observed AEs being neuropsychiatric.…”

“…[11][12][13] The SIMRIKI study also saw 91.2% of their study population achieving the same outcome at 48 weeks. 10 A local study found that 96% of treatment naïve HIV-1 infected patients achieved virologic suppression at the end of 48 weeks of treatment with ABC/3TC + RPV, 14 which was comparable to that of our study in which 98.0% (197/201) of patients who completed follow-up without therapy discontinuation remained virologically suppressed. The ndings of our study reinforce existing primary literature that ABC/3TC + RPV can achieve effective, sustained virologic suppression.…”

“…The AE pro le seen in our study was also very similar to the local study which saw mostly neuropsychiatric AEs at a rate of 46.4% of all observed AEs compared to our study which saw 57.1% of observed AEs being neuropsychiatric. 14 These ndings further support the well-established safety and tolerability of ABC/3TC + RPV.…”

“…Signi cant changes in eCrCl, eGFR and ALTs were rarely noted in other studies on ABC/3TC + RPV, and it is likely that the regimen has no signi cant effect on these laboratory parameters. [11][12][13][14] While no statistically signi cant changes were detected for lipids, fasting blood glucose and HbA1c, the results warrant careful interpretation due to the small number of patients with both baseline and followup values. Remarkably, the SIMRIKI study and the studies by Curran et al and Palacios et al all noted signi cant decreases in total cholesterol and LDL-C, as well as increases in HDL-C. [10][11][12] However, the local study by Ho et al did not lend evidence to any signi cant effect of the regimen on lipids, 14 and there are no studies so far that we know of that have documented signi cant changes in fasting blood glucose and HbA1c.…”

“…10 The results of the SIMRIKI study are corroborated by several similar Spanish studies. [11][12][13] A local study has also shown the e cacy and safety of this regimen in treatment naïve HIV-1 infected adults, 14 but to our knowledge, there have not been any studies on the effectiveness and safety of ABC/3TC + RPV as a switch regimen in Singapore.…”