A first in human study of patients with both inflammatory bowel disease (IBD) and HIV found that administering a drug for IBD disrupts congregating T cells infected with HIV in the gut - which form a persistent reservoir of infection. The compound, called vedolizumab (VDZ), could someday help research efforts to develop a cure for HIV. Although modern antiviral medications can keep HIV at bay, there is still no treatment that eliminates the virus from the body. One key roadblock is the virus's ability to infect T cells that reside in the mucosal tissues of the gastrointestinal (GI) tract. Reducing or eliminating this viral reservoir is a major goal for HIV researchers, but additional investigation is needed to develop a safe and effective therapy. Here, Mathieu Uzzan et al. focused on T cells harboring a4ß7, a protein that mediates the migration of immune cells into certain portions of the GI tract. They administered VDZ - currently a frontline treatment for IBD that targets a4ß7 - to a group of six IBD patients who were also HIV positive and monitored them for 30 weeks through blood tests and colonoscopies carried out before and after treatment. VDZ thwarted formation of the T cell clusters in subjects' small intestines, and proved safe over the study's duration. These results support the idea that anti-a4ß7 therapy could be an important tool in the ongoing quest to eradicate HIV, the authors say.