Eurofins SF Analytical Laboratories Receives FDA Warning Letter for Microbial Data Integrity Failures at Horsham Facility

Contract laboratory oversight is under renewed pressure after Eurofins SF Analytical Laboratories, Inc. received an FDA warning letter dated October 6, 2026, citing systemic microbial data integrity failures at its Horsham, Pennsylvania facility, failures that carry direct adulteration implications for every drug product the lab tested on behalf of its pharmaceutical clients.

The letter, issued by CDER under reference number 320-27-05, follows a June 1–3, 2026 inspection of the Horsham site (FEI 3014704316). Investigators documented violations of 21 CFR 211.194(a), which requires laboratory records to include complete data from all tests necessary to confirm compliance with established specifications. The agency found that analysts failed to record "too numerous to count" (TNTC) results from membrane filtration steps, logging only the pour plate counts, an omission that leaves the full microbial burden of tested samples uncharacterised in the official record.

Compounding the recording gap, investigators observed pour plates that were desiccated and cracked yet had results entered as within acceptable limits. Compromised media cannot reliably support uniform microbial growth; any count derived from such a plate, including a passing result, is analytically invalid under CGMP principles. The agency's position is unambiguous: physical condition of the media must be assessed before results are accepted, not after a specification is met.

A third systemic deficiency centres on zero-CFU reporting. The lab's data review procedure did not require secondary analyst verification when an initial plate count was recorded as 0 colony forming units. During the inspection, an investigator identified a visible colony on a plate already logged as 0 CFU. Multiple samples with desiccated plates were recorded at 0 CFU and discarded without secondary review, eliminating any opportunity for retrospective correction. For QA directors managing contract laboratory agreements, the absence of a mandatory secondary check at the 0-CFU threshold represents a gap that standard supplier qualification audits should now explicitly probe.

Because the facility's methods and controls do not conform to CGMP, the agency has determined that drug products tested there are adulterated within the meaning of section 501(a)(2)(B) of the FD&C Act. That designation extends liability upstream to pharmaceutical manufacturers who relied on Eurofins SF's release data, a consequence that reinforces ICH Q10 expectations around quality oversight of external testing partners. FDA reviewed the firm's June 22, 2026 response to the Form FDA 483 and found it insufficient to close the violations.

The warning letter explicitly states that failure to adequately address the cited violations may result in seizure or injunction without further notice, setting a measurable remediation deadline that Eurofins SF and its pharmaceutical clients will need to track against any subsequent FDA correspondence.

Source: FDA Center for Drug Evaluation and Research via FDA.gov Warning Letters feed, October 13, 2026.