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# Fennec Pharma Hit with 2nd Complete Response
- URL: https://www.fdaweb.com/fennec-pharma-hit-with-2nd-complete-response/
- Published: 2021-11-30T12:00:00.000Z
- Updated: 2026-09-14T17:23:57.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5150659

FDA has issued Fennec Pharmaceuticals a second complete response letter on its NDA for Pedmark (sodium thiosulfate, intravenous) for preventing ototoxicity (hearing loss) associated with cisplatin chemotherapy in pediatric patients with localized, non-metastatic, solid tumors. The letter again cited “manufacturing deficiencies,” which the company says need to be satisfactorily resolved before the submission can be approved.

Fennec’s first complete response letter was issued 8/20/2020 and cited manufacturing concerns from a pre-approval inspection that must be resolved prior to approving the drug ([see earlier story](https://www.fdaweb.com/fennec-pharma-complete-response-on-pedmark/)). The NDA was resubmitted in June, with the agency setting a user fee review action date of 11/27.

Fennec says it is common for platinum-based therapies to cause ototoxicity in pediatric patients. The submission was based on data from two Phase 3 clinical studies of survival and reduction of ototoxicity — the Clinical Oncology Group Protocols ACCL0431 and SIOPEL 6\. Data showed that sodium thiosulfate protects against cisplatin-induced hearing loss in children and is not associated with serious adverse events, the company says.

Fennec plans to request a Type A meeting with the agency to discuss the issues and “other matters” described in the recent letter.