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  5. Signature Biologics, LLC - 631039 - 02/21/2025
  1. Warning Letters

CLOSEOUT LETTER

Signature Biologics, LLC MARCS-CMS 631039 —

Delivery Method:
Via Email
Product:
Biologics
Recipient:
Recipient Name
Neil H. Riordan, Ph.D.
Recipient Title
Chief Executive Officer
Signature Biologics, LLC

4040 W. Royal Lane, Suite 100
Irving, TX 75063-2844
United States

neil@aidanresearch.com
Issuing Office:
Division of Biological Products Operations II

United States

Secondary Issuing Offices

United States

Dear Dr. Neil H. Riordan:

The United States Food and Drug Administration (FDA) has reviewed your firm’s corrective actions in response to Warning Letter #OBPO 23-631039 issued to you on September 18, 2023. Based on our evaluation of your response, your cessation of manufacture and distribution of Signature Matrix, Signature MatrixHX, and Signature Cord, and your destruction of product inventory, it appears that you have addressed the violation(s) detailed in the Warning Letter. Future FDA inspections and regulatory activities will further assess the adequacy and sustainability of your corrective actions.

This letter does not relieve you or your firm from the responsibility of taking all necessary steps to ensure sustained compliance with the Federal Food, Drug, and Cosmetic Act, the Public Health Service Act, their implementing regulations, or other relevant legal authority. The Agency expects you and your firm to maintain compliance and will continue to monitor your state of compliance. This letter will not preclude any future regulatory action should violations be observed during a subsequent inspection or through other means.


Sincerely,
/S/
Melissa J. Mendoza
Director
Office of Compliance and Biologics Quality
Center for Biologics Evaluation and Research

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