Acer Therapeutics NDA Resubmission Accepted
FDA has accepted for review an Acer Therapeutics NDA resubmission for ACER-001 (sodium phenylbutyrate) for oral suspension for treating patients with urea cycle disorders (UCDs). The resubmission addresses items raised by the agency in a complete response letter issued last month, which identified the company’s third-party contract packaging manufacturer as the primary driver for the letter because it wasn’t ready for inspection. The agency has set a user fee review action target date of 1/15/2023.
Acer says it stated in the resubmission that the third-party facility is now ready for inspection. While it says FDA did not cite any other approvability issues in the letter, it did request additional existing nonclinical information which was identified as “not an approvability issue,” as well as labeling and other routine updates to the original NDA. These information updates were also included in the resubmission.
Previously, Acer said its original submission was based on data from two bioequivalence trials in which Acer-001 showed similar relative bioavailability to the reference drug, Ucyclyd Pharma’s Buphenyl. UCDs are caused by genetic mutations that result in a deficiency in one of the six enzymes that catalyze the urea cycle, which can lead to an excess accumulation of ammonia in the bloodstream (hyperammonemia), Acer says. “Acute hyperammonemia can cause lethargy, somnolence, coma, and multi-organ failure, while chronic hyperammonemia can lead to headaches, confusion, lethargy, failure to thrive, behavioral changes, and learning and cognitive deficits,” it says.