Second-Generation Human Immunodeficiency Virus Integrase Inhibitors Induce Differentiation Dysregulation and Exert Toxic Effects in Human Embryonic Stem Cell and Mouse Models

Background Each year, approximately 1.1 million children are exposed in utero to human immunodeficiency virus antiretrovirals, yet their safety is often not well characterized during pregnancy. The Tsepamo study reported a neural tube defect signal in infants exposed to the integrase strand transfer inhibitor (InSTI) dolutegravir from conception, suggesting that exposure during early fetal development may be detrimental Methods The effects of InSTIs on 2 human embryonic stem cell (hESC) lines were characterized with respect to markers of pluripotency, early differentiation, and cellular health. In addition, fetal resorptions after exposure to InSTIs from conception were analyzed in pregnant mice. Results At subtherapeutic concentrations, second-generation InSTIs bictegravir, cabotegravir, and dolutegravir decreased hESC counts and pluripotency and induced dysregulation of genes involved in early differentiation. At therapeutic concentrations, bictegravir induced substantial hESC death and fetal resorptions. It is notable that first-generation InSTI raltegravir did not induce any hESC toxicity or differentiation, at any concentration tested. Conclusions Exposure to some InSTIs, even at subtherapeutic concentrations, can induce adverse effects in hESCs and pregnant mice. Given the increasingly prevalent use of second-generation InSTIs, including in women of reproductive age, it is imperative to further elucidate the effect of InSTIs on embryonic development, as well as their long-term safety after in utero exposure. Toxicity of pregnancy-relevant HIV antiretrovirals were evaluated using 2 human embryonic stem cell models and a pregnancy mouse model. Second-generation integrase inhibitors dolutegravir, bictegravir, and cabotegravir, but not first-generation raltegravir, exhibited toxicity in both in vitro and in vivo models.