The US Food and Drug Administration (FDA) has lifted the full clinical hold on Protagonist Therapeutics’ study of its therapy, rusfertide.
Rusfertide is an experimental product candidate in the developmental stage.
As per the latest FDA direction, Protagonist can resume dosing of the subjects in all trials of rusfertide.
Last month, the company received verbal communication from the FDA placing a hold on the trials.
The clinical hold followed Protagonist’s notification to the regulatory authority of a recent non-clinical finding in a 26-week rasH2 transgenic mouse model study.
The rasH2 model is intended to discover signals associated with tumorigenicity.
This study observed benign and malignant subcutaneous skin tumours.
A re-analysis of the four cases of cancer reported across all rusfertide trials comprising more than 160 patients were conducted along with a complete review of the safety database.
This data comprised cases of suspected unexpected serious adverse reactions (SUSAR).
No new cases of cancer and any other unexpected safety signals were reported, Protagonist said.
The company submitted all the data required by the FDA as the basis for a complete response and to lift the hold on trials.
Protagonist also provided individual patient clinical safety reports to the agency, modified the investigator brochure as well as participant informed consent forms.
Furthermore, new safety and stopping rules were added to the trial protocols.
Protagonist president and CEO Dinesh Patel said: “We are extremely pleased that the FDA has acted so quickly in lifting the clinical hold on the rusfertide development programme, allowing us to resume patient dosing in our clinical studies.”
“We are actively preparing to initiate the Phase III registrational study for polycythemia vera in the first quarter of 2022.
“Protagonist will continue to work closely with the FDA to ensure patient safety with amendments to current and planned future studies with rusfertide.”