Long-term outcome of dolutegravir-containing regimens according to sex: data from the ICONA study

Objectives To compare the long-term risk of treatment failure of dolutegravir-based ART in men and women in a real-life setting. Patients and methods Persons living with HIV (PLWH) from the ICONA cohort were included if they had started dolutegravir in a two- or three-drug regimen as ART-naive or as virologically controlled ART-experienced. The primary endpoint was time to treatment failure (virological/clinical failure or dolutegravir discontinuation). Secondary endpoints were: time to dolutegravir discontinuation due to toxicity and to neuropsychiatric adverse events; and time to virological failure. Cox regression analyses focused on differences in outcomes by sex. Results A total of 2304 PLWH (15% women) initiated dolutegravir-based therapy from ART-naive, and 1916 (19.8% women) while experienced. After a median follow-up of 2.2 (IQR: 0.9-3.9) years in ART-naive and 2.4 (IQR: 1.1-4.3) years in experienced, the 4-year cumulative probability of treatment failure was 33% (95% CI 30.5-35.1) and 20% (95% CI 17.8-22.3), respectively. In the multivariable analyses, in ART-naive the risk of treatment failure was higher for women, but not different after excluding women discontinuing dolutegravir for pregnancy concerns. We also observed a higher risk of discontinuation for toxicity in women (ART-naives: Adjusted Hazard Ratio (AHR): 1.56%; 95% CI: 1.03-2.37; ART-experienced: AHR: 1.53%; 95% CI: 1.01-2.32), although the absolute 4-year probability was low: 7.7% (95% CI 6.5-9.2) in ART-naive and 8.3% (95% CI 6.9-9.9) in experienced. Conclusions In our cohort of PLWH treated with dolutegravir-based regimens and followed up for up to 4 years, we observed a low risk of treatment failure and no evidence for a difference by sex, after excluding discontinuation due to pregnancy concerns. However, we observed a higher risk of dolutegravir discontinuation for toxicity in women.