Integrase inhibitors in children and adolescents: clinical use and resistance.

BACKGROUND: Although integrase inhibitor (INI)-based regimens are now the first-line choice for all people living with HIV, experience among children and adolescents is still scarce. We describe the characteristics and outcomes of a paediatric/adolescent cohort on INI-based ART. METHODS: Retrospective analysis of HIV-infected patients below 18 years of age who started an INI-based regimen from 2007 to 2019, enrolled in the Spanish National Adult (CoRIS) and Paediatric (CoRISpe) cohorts. Resistance mutations were identified by the Stanford HIV Drug Resistance Database. RESULTS: Overall, 318 INI-based regimens were implemented in 288 patients [53.8% female; median age at start of 14.3 years (IQR 12.0-16.3)]. Most were born in Spain (69.1%), vertically infected (87.7%) and treatment-experienced (92.7%). The most frequently prescribed INI was dolutegravir (134; 42.1%), followed by raltegravir (110; 34.6%) and elvitegravir (73; 23.0%). The median exposure was 2.0 years (IQR 1.1-3.0). The main reasons to start an INI-based therapy were treatment simplification (54.4%) and virological failure (34.3%). In total, 103 (32.4%) patients interrupted their regimen: 14.5% for simplification and 8.5% due to virological failure. Most subjects who received dolutegravir (85.8%) and elvitegravir (83.6%) did not interrupt their regimen and maintained undetectable viral load. There were only five virological failures with dolutegravir and three with elvitegravir. There were no interruptions related to adverse events. Seven patients with virological failure presented major resistance mutations to INIs; none of them were on dolutegravir. CONCLUSIONS: INI-based regimens were effective and safe for HIV treatment in children and adolescents. Dolutegravir and elvitegravir presented an excellent profile, and most patients achieved and maintained viral suppression.