FDA 483 - Dr. Reddy's Laboratories Limited CTO VI - June 07, 2024

The FDA Form 483 details significant deficiencies at a facility manufacturing Active Pharmaceutical Ingredients (APIs) with active US Drug Master Files (DMFs), distributed to customers and currently in the market.

**Key Violations and Observations:**

1. **Analytical Method Validation:** Analytical methods for final API testing, including in-house and compendial methods, were not validated or verified under actual conditions of use. This includes methods for water content, residual API quantitation, and GC residual solvent analysis. A customer complaint (200428799) identified an OOS for water content in a released API batch (Batch#) due to a non-validated method. An unknown peak, characterized as [specific impurity], was identified in approximately [number] batches from 2020-2023 during GC residual solvent analysis. Despite establishing an internal control limit and developing an ion chromatography method (01May2022), approximately [number] shipped batches, including those for US marketed products, were not retested using the validated procedure.

2. **Process Validation and Control:** Manufacturing processes are not maintained in a validated state. From May 2022 to January 2024, 17 OOS results for [specific impurity] in API led to reprocessing of all 17 batches, including approximately [number] for US marketed products. Hypothesized root causes included humidity control and material hold times