Shanghai, China-based biotech Hope Medicine Inc. (HopeMed) announced that the US FDA has granted Fast Track Designation (FTD) for HMI-115, the company’s first-in-class prolactin receptor (PRLR)-targeted monoclonal antibody for endometriosis.
HMI-115 previously achieved proof-of-concept in a randomized, placebo-controlled Phase II trial, in which patients with surgically confirmed endometriosis recorded statistically significant reductions in both dysmenorrhea and non-menstrual pelvic pain. Across dose groups, the 240mg every-two-weeks regimen delivered the deepest and most durable improvements. Importantly, the antibody’s effect was achieved without hormonal suppression, a key differentiator from existing medical therapies that often carry significant tolerability and long-term safety constraints.
Endometriosis affects millions of women globally and can lead to chronic pain, infertility, and reduced quality of life. Current pharmacologic therapies rely heavily on hormonal suppression, contributing to side-effects ranging from bone-density loss to menopausal symptoms.
PRLR, a cytokine-family receptor expressed in reproductive, endocrine, and central-nervous-system tissues, mediates the diverse actions of prolactin via JAK-STAT signaling. Its presence in endometriotic lesions suggests a role in disease pathogenesis, with prolactin-driven effects on cell proliferation, inflammation, and survival of ectopic endometrial cells. Blockade of PRLR signaling via HMI-115 may therefore offer a non-hormonal therapeutic approach, reducing lesion viability and local inflammation while preserving ovarian function.
The industry context
HMI-115 (formerly BAY-1158061) was discovered by Bayer AG and licensed exclusively to HopeMed in 2019. Under the agreement, HopeMed assumed global responsibility for development across endometriosis, androgenetic alopecia (AGA), and other prolactin-mediated diseases. A Phase 2 trial in AGA completed last year. In the PRLR-targeted space, the only other active global competitor is Absci’s ABS-201, an AI-designed PRLR antibody currently in Phase 2 for alopecia.
Fast Track Designation reflects the FDA belief that HMI-115 may address a serious unmet medical need and enables more frequent interactions with the agency, rolling submission of regulatory documents, and potential eligibility for accelerated approval if supported by appropriate surrogate endpoints. HopeMed is preparing for a pivotal-stage trial in endometriosis and will meet with FDA to define Phase 3 design while advancing broader global development.