Dual therapy combining raltegravir with etravirine maintains a high level of viral suppression over 96 weeks in long-term experienced HIV-infected individuals over 45 years on a PI-based regimen: results from the Phase II ANRS 163 ETRAL study

Background: Dual therapy combining integrase inhibitors and NNRTIs represents a promising regimen in ageing HIV-infected individuals with long exposure to nucleoside analogues and PIs. Methods: The ANRS 163 ETRAL trial (NCT02212379) was a 96 week, multicentre, single-arm study evaluating the efficacy and safety of raltegravir (400 mg twice daily)/etravirine (200 mg twice daily) in individuals >45 years, on a PI-containing regimen who were integrase inhibitor and etravirine naive. The primary endpoint was the proportion of participants with virological success, defined by the absence of virological failure up to week 48. Main secondary outcomes included evolution of metabolic parameters, CD4/CD8 count, bone mineral density and inflammatory markers. The study was designed to show an efficacy >90%, assuming a success rate >= 95%, with a power of 80% and a 5% type-1 error. Results: One hundred and sixty-five participants (median age 52 years, duration of ART 16.9 years, viral suppression 6.9 years and CD4 count 700 cells/mm3) were enrolled. By ITT analysis, viral suppression was maintained in 99.4% of participants (95% CI = 95.6%-99.9%) at week 48 and 98.7% (95% CI = 95.0%-99.7%) at week 96. Two virological failures occurred (week 24 and week 64) without emergence of integrase inhibitor resistance. Eight participants discontinued raltegravir/etravirine for adverse events, leading to a strategy success rate of 95.1% (95% CI = 90.5%-97.5%) at week 48 and 92.7% (95% CI = 87.5%-95.8%) at week 96. Over 96 weeks, lipid fractions improved (P < 0.001), CD4/CD8 ratio increased, IFN -induced protein 10 (IP-10) decreased (-8.1%), soluble CD14 decreased (-27%, P < 0.001) bone mineral density improved and BMI increased. Conclusions: Raltegravir plus etravirine dual therapy demonstrated durable efficacy in virologically suppressed ageing patients.