Regeneron Prostate Cancer Trial Stops Enrollment
After reporting two patient deaths, Regeneron says it has discontinued enrollment in a Phase 1 prostate cancer study of REGN5678, the company’s PSMAxCD38 costimulatory bispecific antibody, used in combination with a full-dose of its programmed death receptor-1 inhibitor Libtayo (cemiplimab-rwlc). The company says it plans to assess REGN5678 combinations with lower doses of Libtayo. It also plans to enroll patients in a REGN5678 monotherapy cohort, as well as in combination with other immunotherapy modalities. Recently released preliminary data on REGN5678 plus cemiplimab in patients with prostate cancer showed the first evidence of clinical activity of a CD28 co-stimulatory bispecific antibody in solid tumors.