A Phase I study that evaluated whether a microbicide gel called PC-1005 is safe for use in the rectum. The study, which included 12 HIV-negative cisgender and transgender men and women at two sites in the U.S., will help determine whether further testing of the safety and acceptability of PC-1005 as a potential rectal microbicide for preventing HIV and other sexually transmitted infections (STIs) can be conducted in a larger population. PC-1500 is the only product designed for vaginal and rectal use targeting HIV, herpes simplex virus (HSV) and human papillomavirus (HPV) simultaneously that has undergone Phase 1 testing to date. MTN-037 is the first study of PC-1005 used rectally. Results are anticipated by mid- to late 2020.