Proactive Mitigation of Regulatory Uncertainty and Diversification of Manufacturing Strategy

Biotech company Scholar Rock (Scholar Rock, SRRK) has decided to exclude Catalent's (Catalent) Bloomington, Indiana fill-finish facility from the resubmission process for its apitegromab (apitegromab) drug, a treatment candidate for spinal muscular atrophy (SMA), to the U.S. Food and Drug Administration (FDA). This decision aims to circumvent the regulatory risks associated with the facility, which recently received an Official Action Indicated (OAI) rating during an FDA inspection. By consolidating the fill-finish process at a second manufacturing facility with a proven track record of regulatory compliance, Scholar Rock intends to prevent delays in the Prescription Drug User Fee Act (PDUFA) target review date of September 30, 2026. This strategic move demonstrates proactive risk management to ensure that manufacturing facility instability does not become a final hurdle in the approval process, thereby contributing to maintaining market confidence.

Securing Review Timeline Through Consolidation of Fill-Finish Process

In 2025, Scholar Rock received a Complete Response Letter (CRL) for its initial FDA approval application, citing issues with Catalent's facility, including a Form 483 observation and a Warning Letter. For the 2026 resubmission, the company included two additional facilities, including a second Catalent facility already engaged in large-scale commercial manufacturing of drug products, to diversify risk. However, a reinspection of the Catalent facility in April 2026 resulted in another Form 483 with additional deficiencies, leading to an OAI rating. Scholar Rock's swift relocation to an alternative facility demonstrates that having a backup manufacturing capacity served as a critical safeguard against regulatory review delays.

Novo Nordisk's Acquisition Legacy and Subsequent Regulatory Issues

The problematic Bloomington facility was acquired by Novo Holdings, the parent company of Novo Nordisk (Novo Nordisk), in 2024 to address the surging demand for its obesity drug, Wegovy (Wegovy). However, ongoing quality control violations at this fill-finish facility have led to a chain reaction, causing delays or cancellations in FDA approvals for other pharmaceutical companies, including Regeneron's Eylea HD prefilled syringe and Incyte's Zynyz for lung cancer. While Novo Nordisk has pledged to invest significant resources to improve quality, existing contract manufacturing customers are forced to diversify their supply chains to avoid disruptions to their commercialization timelines.

Global Regulatory Diversification and Supply Chain Coordination Challenges

Scholar Rock has submitted an application for apitegromab to the European Medicines Agency (EMA) as well, but the application still lists only the Catalent facility. The EMA has been awaiting the results of the FDA inspection before making a final decision. Therefore, Scholar Rock has initiated discussions with European authorities to expedite the addition of a second fill-finish facility to the EMA application. To secure U.S. approval and stabilize the global commercial supply chain, Scholar Rock will face short-term operational burdens in meeting dual regulatory standards. However, with large-scale commercial production of the drug substance already completed, the company expects that timely market launch will minimize long-term supply chain disruptions.

Market Expectations as the First Muscle-Targeting SMA Therapy

Apitegromab is a novel fully human monoclonal antibody that selectively inhibits the activation of myostatin, a precursor that interferes with muscle growth. In the Phase 3 SAPPHIRE study, apitegromab demonstrated significant improvements in motor function when used in combination with existing neuroprotective therapies such as Biogen's Spinraza (Spinraza) and Roche's Evrysdi (Evrysdi). As the only muscle-improving adjunctive therapy to be used in combination with existing gene or survival motor neuron (SMN)-targeting therapies, apitegromab has the potential to establish a dominant position in the global SMA treatment market, which is estimated to be worth billions of dollars annually.