Zydus Life Science , a global pharmaceutical company, has announced that its U.S.-based subsidiary, Sentynl Therapeutics, has received a Complete Response Letter (CRL) from the U.S. Food and Drug Administration (FDA) regarding its New Drug Application (NDA) for CUTX-101. This development marks a significant milestone in the company's efforts to bring a new treatment for Menkes disease to the market.

FDA Response and Next Steps

The FDA's Complete Response Letter primarily focuses on manufacturing concerns rather than the drug's efficacy or safety profile. Specifically, the agency mentioned the need for a Current Good Manufacturing Practice (CGMP) inspection of the facility where CUTX-101 is produced.

Zydus Lifesciences has already provided responses to the FDA's re-inspection, demonstrating the facility's CGMP compliance. The company is currently awaiting the FDA's Establishment Inspection Report (EIR).

Matt Heck, CEO of Sentynl Therapeutics, stated, "We recognize the FDA's decision and remain dedicated to working with the Agency to clarify next steps. Our commitment to patients is unchanged. We believe in the promise of our therapy and are prepared to address the feedback and pursue resubmission promptly."

About CUTX-101 and Menkes Disease

CUTX-101 is a subcutaneous injectable formulation of copper histidinate designed to treat Menkes disease, a rare X-linked recessive pediatric genetic disorder. The condition affects an estimated 1 in 34,810 to 1 in 8,664 live male births and is characterized by the body's inability to absorb dietary copper effectively.

Patients with Menkes disease experience impaired copper transport across the blood-brain barrier, leading to distinctive clinical features such as:

• Sparse and depigmented hair
• Connective tissue problems
• Severe neurological symptoms

Without treatment, mortality is high, with many patients succumbing to the disease between 2-3 years of age.

Clinical Efficacy and Regulatory Status

The CUTX-101 NDA was initially granted Priority Review by the FDA, supported by positive topline clinical efficacy results. These results demonstrated a significant improvement in overall survival for Menkes disease patients who received early treatment with CUTX-101.

It's important to note that the FDA's Complete Response Letter did not cite any concerns regarding the drug's efficacy or safety data. This suggests that the primary hurdle for approval lies in addressing the manufacturing-related issues raised by the agency.

Looking Ahead

Sentynl Therapeutics plans to request a meeting with the FDA to discuss the Complete Response Letter and the resubmission of the CUTX-101 NDA. The company remains committed to bringing this potentially life-changing treatment to patients with Menkes disease.

As Zydus Lifesciences and Sentynl Therapeutics work to address the FDA's feedback, the rare disease community will be watching closely, hoping for a positive outcome that could provide a new treatment option for this devastating genetic disorder.

Zydus Lifesciences has announced another extension for its planned acquisition of Sterling Biotech Limited's (SBL) Active Pharmaceutical Ingredients (API) business. The company has now extended the closing date to June 30, 2026, marking the second extension since the original agreement was signed.

Timeline of Extensions

The acquisition timeline has seen multiple adjustments since the initial agreement. The following table outlines the progression of deadlines:

Reasons for Latest Extension

According to the company's latest regulatory filing dated December 24, 2025, Sterling Biotech is still working to complete certain conditions precedent outlined in the Business Transfer Agreement. Zydus Lifesciences stated that "SBL is still in the process of completing certain conditions precedents of the BTA and hence the Company and SBL have executed a letter to extend the closing date by June 30, 2026."

Transaction Details

The acquisition involves Sterling Biotech's API business, which represents a strategic expansion for Zydus Lifesciences in the pharmaceutical ingredients sector. The deal remains subject to the completion of various conditions precedent as specified in the original Business Transfer Agreement.

Regulatory Compliance

The company has maintained transparency throughout the process, informing stock exchanges about each development in compliance with Regulation 30 of the SEBI (Listing Obligations and Disclosure Requirements) Regulations, 2015. The latest update was communicated to both BSE Limited and National Stock Exchange of India Limited.

Strategic Outlook

Despite the extended timeline, Zydus Lifesciences remains committed to completing the acquisition. The company expressed confidence that "the transaction is expected to be completed on or before June 30, 2026." The repeated extensions suggest the complexity of fulfilling all prerequisite conditions while maintaining the strategic value of the deal for both parties involved.