Sentynl Therapeutics Achieves FDA Acceptance for CUTX-101 Resubmission

Sentynl Therapeutics, Inc., a biopharmaceutical company situated in the United States and owned by Zydus Lifesciences, has announced an important milestone in its efforts to treat Menkes disease, a rare genetic condition affecting children. On December 15, 2025, the U.S. Food and Drug Administration (FDA) accepted the company's resubmission of its New Drug Application (NDA) for CUTX-101, a copper histidinate that aims to address this serious health issue in pediatric patients.

New PDUFA Date: A Step Forward

The acceptance comes with a new PDUFA (Prescription Drug User Fee Act) action date of January 14, 2026. This new timeline represents a crucial development for Sentynl as its CEO, Matt Heck, expressed appreciation for the FDA's partnership in reviewing the application expeditiously. He emphasized how this acceptance brings them closer to reaching a significant milestone for families affected by Menkes disease.

Sentynl had submitted its revised NDA just a month earlier, on November 14, 2025, in response to a complete response letter (CRL) received from the FDA on September 30, 2025. The original CRL pointed out issues related to the manufacturing site’s cGMP (current Good Manufacturing Practices) compliance, though it did not raise any concerns regarding the safety or efficacy of CUTX-101's data. This highlights the importance of ensuring compliant manufacturing processes in the pharmaceutical industry.

CUTX-101: A Glimmer of Hope

If approved, CUTX-101 will become the first and only FDA-approved treatment specifically for Menkes disease. This severe genetic disorder impacts an estimated 1 in 34,810 live male births, and in some cases, as many as 1 in 8,664 male births. The disease is characterized by a lack of copper transport in the body, resulting in neurological and physical developmental issues. Early treatment is crucial to improve survival prospects and neurodevelopmental outcomes for affected children.

Scientific Background and Clinical Evidence

CUTX-101, delivered as a subcutaneous injectable, is designed to provide better tolerability due to its physiological pH level. Promising results from a Phase 1/2 clinical trial conducted by Dr. Stephen G. Kaler at the National Institutes of Health (NIH) found significant improvements in survival rates for subjects receiving early treatment with CUTX-101. Not only did early intervention lead to neurodevelopmental enhancements, but it also resulted in a remarkable nearly 80% reduction in the risk of death compared to untreated individuals from historical control cohorts. The median overall survival jumped from 16.1 months for untreated patients to an astounding 177.1 months for those receiving CUTX-101. This robust clinical data serves as a beacon of hope for patients and families grappling with the effects of Menkes disease.

Moreover, CUTX-101 has garnered multiple FDA designations, including Breakthrough Therapy and Orphan Drug status, underscoring its potential significance in treating rare pediatric diseases. The European Medicines Agency has similarly granted Orphan Designation, further expanding its potential reach on a global scale.

The Role of Zydus Lifesciences

Sentynl Therapeutics is part of Zydus Lifesciences, a company committed to advancing healthcare solutions with an emphasis on innovative therapies for rare diseases. This collaboration enables the expansion of the research, development, and delivery of life-saving treatments to patients around the world. Zydus Lifesciences employs around 27,000 individuals, including a dedicated research team of 1,500 scientists.

Conclusion

The acceptance of the NDA resubmission for CUTX-101 represents a significant step towards addressing the urgent needs of children suffering from Menkes disease. With the new PDUFA date set for January 14, 2026, the healthcare community eagerly anticipates the official review process as Sentynl strives to make this innovative treatment available. As we await further developments, the families impacted by Menkes disease hold onto the hope that CUTX-101 will provide a brighter future.