FDA WARNING_LETTER - Pfizer Inc. - June 03, 2009

The FDA issued a Warning Letter to Pfizer, Inc. following an inspection from May 4 to June 3, 2009, concerning their role as sponsor for clinical investigation Protocol (b)(4) of investigational drug (b)(4). The inspection was prompted by significant violations found at several clinical investigator sites.

The FDA concluded that Pfizer failed to adhere to statutory requirements and FDA regulations governing clinical investigations. Key violations include:

1. **Failure to ensure proper monitoring (21 CFR 312.50):** This was a repeat violation. Inadequate monitoring led to widespread, undetected, and uncorrected overdosing of pediatric subjects at multiple sites, with some subjects overdosed for extended periods (e.g., 22 days). Overdosing continued even after Pfizer retrained monitors. 2. **Failure to ensure investigations were conducted in accordance with the IND's general investigational plan and protocols (21 CFR 312.50):** * Subjects at multiple sites received incorrect doses, with 40 subjects having dosing errors and 20 exceeding maximum protocol doses. * Dosing titration plans were not developed or followed at multiple sites. * ECGs were not consistently reviewed by qualified physicians as required. * The (b)(4) assessment was not administered by qualified personnel, and Pfizer lacked a required rater qualification program. * Diagnostic