SIDE EFFECTS BY FREQUENCY OF USE WITH EVO100 VAGINAL GEL: Results FROM THE PHASE 2B/3 AMPREVENCE TRIAL

EVO100 is an investigational antimicrobial, pH-modulating vaginal gel being evaluated for the prevention of sexually transmitted infections. The objective of the current analysis is to report on side effects by frequency of study drug use. AMPREVENCE (NCT03107377) was a phase 2B/3, placebo-controlled, multicenter study conducted over approximately 16 weeks in women at risk of urogenital Chlamydia trachomatis (CT) and Neisseria gonorrhea (GC) infection. Sexually active, healthy women 18–45 years old who had documented CT or GC infection within 16 weeks of enrollment were randomized 1:1 to receive EVO100 or placebo. The primary and secondary objectives were the incident infection of CT or GC, respectively. Safety was assessed through adverse event (AE) reporting. Of 860 women enrolled (EVO100: n=426; placebo: n=434), 764 were included in the safety analysis (EVO100: n=376; placebo: n=388). Overall, 159 women (EVO100: n=80; placebo: n=79) had an AE on study, with the most commonly reported AEs being vaginal candidiasis (n=19, 5%), vaginal discharge (n=12, 3%), and urinary tract infection (UTI; n=12, 3%) for EVO100 users; and bacterial vaginosis (n=18, 5%), UTI (n=10, 3%), and vaginal discharge (n=10, 3%) for placebo users (Chappell et al, Am J Obstet Gynecol 2021). The maximum frequency of product use/week ranged between 1 and 20 times for both arms. Study weeks were analyzed to determine if there was an association between the incidence of AEs and frequency of product use. There were 2818 and 2859 weeks reported with EVO100 and placebo use, respectively. Of 1277 and 1290 study weeks where EVO100 or placebo was used once/week, respectively, the rate of AEs/week was similar for EVO100 (n=19, 1%) and placebo (n=18, 1%). The most commonly reported AE with once/week product use was vaginal candidiasis (n=8, <1%) for EVO100 and bacterial vaginosis (n=6, <1%) for placebo. Of 1541 and 1569 weeks where EVO100 or placebo was used ≥2/week, respectively, the rate of AEs/week was similar for EVO100 (n=18, 1%) and placebo (n=17, 1%) use. The most commonly reported AE with ≥2/week product use was vaginal candidiasis (n=3, <1%) for EVO100 and vaginal discharge (n=4, <1%) for placebo. In AMPREVENCE, the incidence of AEs was similar between EVO100 and placebo and did not increase with more frequent use of either product.