About Sermonix

Company Overview


Sermonix Pharmaceuticals Inc is a privately held, Ohio-based biopharmaceutical company with a precision medicine focus for bringing targeted oncology products through development, approval, and commercialization. Sermonix’s lead candidate is oral lasofoxifene. Lasofoxifene is an investigational novel endocrine therapy in clinical development which has demonstrated robust target engagement as an antagonist at the breast particularly in the presence of ESR1 mutations. Lasofoxifene has unique tissue selectivity distinguishing it from other current and investigational endocrine therapies with beneficial effects seen on vagina and bone in previous clinical studies.  Sermonix is currently focused on the study of lasofoxifene for advanced breast cancer treatment, particularly in patients with locally advanced or metastatic hormone receptor-positive (ER+)/human epidermal growth factor 2-negative (HER2-) breast cancer who have developed an ESR1 mutation.

New activity in ESR1 mutations was discovered in the laboratory of Donald McDonnell, MD, at Duke University, and Sermonix has exclusive rights to develop and, if FDA-approved, commercialize lasofoxifene in this important area of unmet medical need.

The company was founded in 2014 by David Portman, MD, a leading clinical researcher and expert in women’s health, sexual medicine and menopause, and SERM therapy.