NEWARK, Calif., Sept. 17, 2021 /PRNewswire/ — Protagonist Therapeutics, Inc. (Nasdaq: PTGX) (“Protagonist” or “the Company”) today announced the receipt of a verbal communication from the U.S. Food and Drug Administration (FDA) that Protagonist’s clinical studies for rusfertide, an investigational product candidate currently in development, have been placed on a clinical hold.
The clinical hold follows Protagonist’s notification to the FDA of a recent non-clinical finding in a 26-week rasH2 transgenic mouse model study. The rasH2 model is designed to detect signals related to tumorigenicity, and benign and malignant subcutaneous skin tumors were observed in this study.
The Company is working with the FDA and will be prepared to make all appropriate updates to clinical study documents and determine the next steps in consultation with the FDA. In particular, we will provide additional clinical safety reports, update the investigator brochures and patient informed consent forms, and make necessary modifications to study protocols. Dosing of patients in all ongoing clinical trials with rusfertide will be put on hold, and study investigators have been contacted to facilitate patient notification.