Probability of Starting Two-Drug Regimen (2DR) vs. Three-Drug Regimen (3DR) in ART-Naïve and ART-Experienced Person with HIV (PWH) Across the First Wave of COVID-19 Pandemic

This study examined the impact of the COVID-19 lockdown on antiretroviral therapy (ART) prescriptions among persons living with HIV (PWH) in Italy. Methods: Data from the ICONA cohort included ART-naïve individuals who started ART between January 2019 and December 2022, and ART-experienced individuals who started new ART with HIV RNA ≤50 cps/mL from January 2016 to December 2022. The analysis focused on the proportion of PWH starting or switching to dual (2DR) versus triple (3DR) ART regimens. Comparisons were made using Chisquare and Kruskal-Wallis tests, with logistic regression (LR) to assess associations, adjusting for sex and age. Results: Among 2481 ART-naïve PWH, 17% were female, with a median age of 40. Using 2020 as the comparator (the lockdown year), the odds ratio (OR) from fitting a LR showed a reduced probability of prescribing 2DR both before and after 2020. The proportion of PWH starting 2DR was 9% in 2019, 18% in 2020, 13% in 2021, and 10% in 2022. Among 12,335 ART-experienced PWH, 20% were female, with a median age of 47. The proportion switching to 2DR rose from 24% in 2016 to 38% in 2020, 62% in 2021, and 65% in 2022, showing a >3-fold higher probability to be switched to 2DR instead of 3DR in recent years (2021-2022). Conclusions: For ART-naive PWH, 2DR initiation did not decrease during the 2020 lockdown but changed in the following years, possibly indicating shifts in clinical practice or resuming HIV services. For ART-experienced PWH, 2DR prescriptions increased significantly over time, especially for INSTI-based regimens.