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Notification to Pharmaceutical Companies: Clinical and Bioanalytical Studies Conducted by Synapse Labs Pvt. Ltd. are Unacceptable

[06/18/2024] FDA is notifying sponsors of new drug applications (NDAs) and abbreviated new drug applications (ANDAs) that clinical and bioanalytical studies conducted by Synapse Labs Pvt. Ltd. (Synapse)—a contract research organization (CRO) based in Pune, India—are not acceptable because of data integrity concerns. Studies conducted by Synapse must be repeated.  

During analyses of study data generated at Synapse and submitted in several applications, FDA identified significant unexplained anomalies in the data that indicate the data were falsified. FDA issued an initial general correspondence letter (GCL) to Synapse on February 12, 2024, outlining significant data integrity concerns for bioequivalence studies conducted by the CRO and submitted in support of ANDAs.

FDA issued a second GCL to Synapse describing the agency’s determination that study data from Synapse must be rejected. FDA is requiring sponsors of approved, tentatively approved or pending ANDAs and NDAs to repeat the bioavailability/bioequivalence studies, when those studies are essential for approval, using an entity other than Synapse or any other organization with known unresolved data integrity concerns. FDA encourages affected sponsors to contact the relevant FDA review division in the Office of Generic Drugs or the Office of New Drugs for further information or clarification.

FDA has determined that data from Synapse are not acceptable to support a determination of safety or effectiveness for brand-name drugs, or to show affected generic products are bioequivalent to brand-name products. FDA is changing the therapeutic equivalence rating to “BX” for any currently approved and marketed prescription generic drug applications that relied on data from Synapse until adequate repeat studies are submitted and determined to be adequate to demonstrate bioequivalence. A “BX” rating indicates data reviewed by the agency are insufficient to determine therapeutic equivalence (substitutability) of the generic product to its brand-name product. A drug with a “BX” rating is still approved and can be prescribed, but is not recommended as automatically substitutable at the pharmacy (or by a pharmacist) for the brand-name drug. 

FDA has been investigating postmarketing safety reports for marketing applications that relied on bioavailability/bioequivalence studies conducted by Synapse for approval. To date, the agency has not identified signals related to problems with the safety or quality of the approved drugs. FDA remains vigilant and will act should we identify safety issues. Patients should not make changes to their treatment except in consultation with their health care professional. 

FDA is committed to protecting the health of the American public by holding approved products to high standards of quality, safety and efficacy. 

Additional information


Questions and Answers Regarding Data Integrity Violations at Synapse

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