What FDA cites in its warning letters to drug manufacturers, in figures: 298 letters from 2023-11-06 to 2026-10-27, finding by finding. The problems FDA cites most are the ones a plant can only see by comparing the records of two of its systems.
By area
By CFR section
| Section | What it covers | Letters |
|---|---|---|
| 21 CFR 211.22 | Responsibilities of the quality control unit | 162 · 54% |
| 21 CFR 211.84 | Testing and approval of components | 156 · 52% |
| 21 CFR 211.100 | Written procedures; deviations (production and process control) | 133 · 45% |
| 21 CFR 211.165 | Testing and release for distribution | 104 · 35% |
| 21 CFR 211.192 | Production record review (investigations) | 92 · 31% |
| 21 CFR 211.166 | Stability testing | 88 · 30% |
| 21 CFR 211.160 | Laboratory controls | 61 · 20% |
| 21 CFR 211.67 | Equipment cleaning and maintenance | 61 · 20% |
| 21 CFR 211.113 | Control of microbiological contamination | 51 · 17% |
| 21 CFR 211.42 | Design and construction features | 44 · 15% |
| 21 CFR 211.194 | Laboratory records | 35 · 12% |
| 21 CFR 211.188 | Batch production and control records | 35 · 12% |
| 21 CFR 211.180 | Records: general requirements (product reviews) | 24 · 8% |
| 21 CFR 211.68 | Automatic, mechanical and electronic equipment | 21 · 7% |
| 21 CFR 211.137 | Expiration dating | 19 · 6% |
Where the records live
For each problem, the systems that hold the records showing it. Most problems need two systems compared: a training record against a batch step, a lab result against a release, a logbook against the equipment a batch used.
The 15 problems FDA cites most
| Problem | Area | Records in | Letters |
|---|---|---|---|
| Components released without identity testing (relying on the supplier's CoA) Cross-system | Components and suppliers | ERP / inventory, LIMS / CDS | 156 · 52.3% |
| Quality unit not approving procedures, records and releases Cross-system | Quality unit | Documents (DMS), QMS, ERP / inventory, MES / eBMR | 150 · 50.3% |
| Products made with no process validation Cross-system | Process validation | MES / eBMR, Documents (DMS) | 128 · 43.0% |
| No ongoing stability programme for products on the market Cross-system | Stability | ERP / inventory, LIMS / CDS | 104 · 34.9% |
| Batches released without all required tests Cross-system | Batch records | ERP / inventory, LIMS / CDS | 98 · 32.9% |
| Investigations inadequate: root cause, scope and other batches not covered Cross-system | Deviations, CAPA and change control | QMS, MES / eBMR | 89 · 29.9% |
| Stability pulls missed or tested late | Stability | LIMS / CDS | 88 · 29.5% |
| High-risk components not tested for DEG / EG or methanol Cross-system | Components and suppliers | ERP / inventory, LIMS / CDS | 71 · 23.8% |
| Procedures missing for required activities | Quality unit | Documents (DMS) | 64 · 21.5% |
| Suppliers not qualified or not on the approved list Cross-system | Components and suppliers | ERP / inventory, QMS | 62 · 20.8% |
| Equipment used without a valid cleaning (between products, or clean hold expired) Cross-system | Equipment and cleaning | MES / eBMR, eLogbooks / CMMS | 58 · 19.5% |
| Batch records incomplete when the batch was released Cross-system | Batch records | MES / eBMR, QMS, ERP / inventory | 53 · 17.8% |
| Aseptic processing controls (media fills, interventions, airflow) | Water and environment | MES / eBMR, LIMS / CDS, Documents (DMS) | 53 · 17.8% |
| Methods not validated or suitability not shown | Laboratory and OOS | LIMS / CDS, Documents (DMS) | 46 · 15.4% |
| Water system out of limits without investigation, or not monitored Cross-system | Water and environment | LIMS / CDS, QMS | 45 · 15.1% |
By year and country
| 2023 17 letters | 2024 111 letters | 2025 91 letters | 2026 79 letters |
| United States 143 | China 42 | India 34 | South Korea 12 | Canada 11 | Turkey 8 | France 4 | Malaysia 4 |
Each area
How these figures are made: Siddhi LLC reads FDA's public drug CGMP warning letters (on fda.gov, 2023-11-06 to 2026-10-27: 298 letters, 1315 findings) and groups each finding by the problem it describes, from the CFR section FDA cites and FDA's wording. A letter counts once in an area, and can count in several areas. These are our grouping of FDA's letters, not FDA's own statistics. The systems are where a plant keeps the records that show each problem: FDA cites the regulation, not a system. Updated with each new release of the Atto Audit Library.
Find these problems in your own records before an inspector does
The Atto Auditor compares the exports of your MES, QMS, LIMS, training, documents, logbooks and ERP, whichever vendors made them, and gives your plant's Audit fit summary: each problem FDA cites, with the records that show it.