Fortress Biotech, Inc. (FBIO) shares slumped 30% in the pre-market session on Wednesday after the company announced that the U.S. Food and Drug Administration refused to approve CUTX-101 for the treatment of Menkes disease in pediatric patients.

The FDA, in its letter, flagged concerns about the facility where CUTX-101 is manufactured. The letter did not cite any other approvability concerns or any deficiencies pertaining to CUTX-101's efficacy and safety data, the company said.

U.S.-based biopharmaceutical company Sentyl Therapeutics is responsible for the development and commercialization of CUTX-101. It took over the responsibility from Fortress's majority-owner unit, Cyprium Therapeutics, in December 2023.

Fortress said on Wednesday that Cyprium expects Sentynl to work expeditiously to address the FDA's concerns and pursue resubmission promptly.

On Stocktwits, retail sentiment around FBIO stock rose from 'bullish' to 'extremely bullish' over the past 24 hours, while message volume improved from 'high' to 'extremely high' levels.

The facility in question recently responded to the FDA's September 2025 re-inspection, and Sentynl expects to request a meeting with the agency to discuss resubmission of the drug application, according to Fortress.

Under the deal between Cyprium and Sentynl, Cyprium will be eligible to receive royalties on net sales of CUTX-101, if approved in the treatment of Menkes disease, and up to $129 million in aggregate development and sales milestones from Sentynl. Menkes disease is a rare, severe genetic disorder primarily affecting males, which impairs the body's ability to absorb and distribute copper, resulting in copper deficiency in the brain and other organs.

FBIO stock is up 82% this year and approximately 158% over the past 12 months. 

Read also: Carvana Stock Rallies Pre-Market After Jefferies's Upgrade, Price Target Hike

For updates and corrections, email newsroom[at]stocktwits[dot]com.

MENAFN01102025007385015968ID1110137340