Clinical Report: Why Early QC Planning Matters in Cell and Gene Therapy

Overview

Manufacturing and quality deficiencies account for 74% of Complete Response Letters issued by the FDA from 2020 to 2024.

Background

The translation of quality strategies into actionable plans is critical in cell and gene therapy, where manufacturing and quality issues have led to significant regulatory setbacks. Understanding regulatory expectations is essential.

Data Highlights

No numerical data provided in the article.

Key Findings

• 74% of FDA Complete Response Letters from 2020 to 2024 cited manufacturing or quality deficiencies.
• Three high-profile cell and gene therapy programs were delayed or rejected in July 2025 due to CMC-related issues.
• FDA guidance states that early development decisions carry disproportionate downstream consequences.
• QC continuity is essential for maintaining a cohesive risk logic throughout the development process.
• Regulatory frameworks emphasize the need for early, phase-appropriate CMC and analytical planning.

Clinical Implications

Healthcare professionals involved in cell and gene therapy development should align with regulatory expectations.

Conclusion

Addressing potential deficiencies early can streamline the path to regulatory approval.

Related Resources & Content

1. FDA, FDA Guidance, 2026 -- Chemistry, Manufacturing, and Controls Flexibilities for Developing Human Cellular and Gene Therapy Products for a Biologics License Application
2. Pharma Manufacturing, Pharma Manufacturing, 2024 -- FDA’s CRLs reveal 74% of applications rejected for quality, manufacturing issues
3. The Medicine Maker, The Medicine Maker, 2026 -- When Insight Meets Urgency in Cell and Gene Therapy
4. The Medicine Maker, The Medicine Maker, 2026 -- Building Quality into Advanced Therapies from Day One
5. Drug Safety, Drug Safety, 2025 -- Monitoring Drug Safety in Cell and Gene Therapies: Emerging Issues in Risk Management and Extended Patient Follow-Up
6. Bone Marrow Transplantation — Standardization of Quality Control Assessments for Academic CAR-T Cell Production: A Position Statement from the UNITC Consortium's WP-Bioproduction Team
7. Chemistry, Manufacturing, and Controls Flexibilities for Developing Human Cellular and Gene Therapy Products for a Biologics License Application | FDA
8. FDA’s CRLs reveal 74% of applications rejected for quality, manufacturing issues | Pharma Manufacturing
9. Sustained Clinical Benefit of AAV Gene Therapy in Severe Hemophilia B | New England Journal of Medicine