Phathom Pharmaceuticals Announces Submission of 6-Month Stability Data in Support of Erosive GERD NDA


Phathom Pharmaceuticals, Inc. recently announced it has submitted to the FDA 6-month stability data from its long-term and accelerated stability program for its reformulated vonoprazan tablets. The additional stability was required for the FDA to complete its NDA review for vonoprazan, a novel first-in-class potassium-competitive acid blocker (PCAB), for the treatment of Erosive GERD (gastroesophageal reflux disease), also referred to as erosive esophagitis.

With the submission of these data, Phathom has satisfied the FDA’s request for additional data in response to the Complete Response Letter (CRL) issued in February 2023 relating to specifications and controls for a nitrosamine drug substance related impurity, N-nitroso-vonoprazan (NVP). Phathom resubmitted the NDA for vonoprazan for Erosive GERD in May 2023 on the basis of 3 months of stability data and was assigned a PDUFA goal date of November 17, 2023.

“We are happy to share that the 6-month stability data continue to demonstrate effective control of NVP, which is another big step forward as we prepare for a planned launch in the fourth quarter of this year,” said Terrie Curran, President and Chief Executive Officer of Phathom. “The latest stability data confirm that our minor product reformulation has limited the presence of NVP, and we believe these data comfortably support the proposed shelf-life for vonoprazan tablets. We look forward to working with the FDA as it completes its review.”

The long-term and accelerated 6-month data from Phathom’s stability program have demonstrated that the minor drug product tablet reformulation is controlling NVP growth through 6 months and keeping levels greater than tenfold below the acceptable daily intake limit of 96 ng/day or 2.4 ppm based on the maximum approved daily dose of 40 mg/day.

The NDA seeks regulatory approval for vonoprazan as a treatment for the healing and maintenance of healing of Erosive GERD, and relief of associated heartburn symptoms, and was previously classified as a Class 2 resubmission with a 6-month review period. If approved, a combined US commercial launch for Erosive GERD and H. pylori is planned for the fourth quarter of 2023.

Phathom Pharmaceuticals is a biopharmaceutical company focused on the development and commercialization of novel treatments for gastrointestinal diseases. Phathom has in-licensed the exclusive rights in the US, Europe, and Canada to vonoprazan, a first-in-class potassium-competitive acid blocker (PCAB). For more information, visit www.phathompharma.com.