The Food and Drug Administration (FDA) has granted Breakthrough Therapy designation to seladelpar (CymaBay Therapeutics) for the treatment of early-stage primary biliary cholangitis (PBC).

Seladelpar (previously MBX-8025), a potent and selective peroxisome proliferator-activated receptor delta agonist, is being investigated for use in combination with ursodeoxycholic acid (UDCA) in adults with either an inadequate response to UDCA or as a monotherapy in those unable to tolerate UDCA.  

The FDA’s decision to grant Breakthrough status is based on preliminary results from a Phase 2 clinical trial (CB8025-21629), which showed that seladelpar was associated with a substantial reduction in serum alkaline phosphatase (primary efficacy outcome).

A year-long, Phase 3 trial (ENHANCE) is currently evaluating the safety and efficacy of seladelpar in 240 PBC patients. The primary outcome measure is the responder rate (defined as alkaline phosphatase level <1.67 x ULN with at least a 15% decrease from baseline and a normal level of total bilirubin) after 52 weeks. 

“We look forward to working closely with regulators to complete the seladelpar development program,” said Klara Dickinson, Regulatory and Compliance Officer of CymaBay. “These designations afford us an opportunity to accelerate the access of a new and innovative treatment option for patients with PBC.”

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Seladelpar was previously granted Orphan Drug designation for PBC. Additionally, the Company is conducting a proof-of-concept study of seladelpar as a treatment for nonalcoholic steatohepatitis.

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