Medications Discovery & Toxicology Branch (MDTB)

What We Do:

The MDTB plans and implements a preclinical Addiction Treatment Discovery Program (ATDP), with the goal of identifying potential medications to treat drug dependence disorders. The Program is implemented by coordinating the extramural activities of the MDTB and the Chemistry & Pharmaceutics Branch (CPB) and through close interactions with chemists and pharmaceutical company contacts. Within the ATDP, contract-supported activities range from in vitro receptor activity profiling to compound evaluations in advanced animal models. The MDTB also supports grants aimed at evaluating potential new pharmacotherapies to treat drug dependence.

Beyond medications discovery, the MDTB plans and implements a comprehensive preclinical Toxicology Program. Through contracts, the Toxicology Program supports all of the standard Good Laboratory Practices (GLP) preclinical safety studies required for IND and NDA filings with the FDA. In addition, contracts have been established to support specialized preclinical drug interaction studies in which the safety of potential medications is established in the presence of drugs of abuse.

Staff Biographies and Research Interests:

  • Nathan M. Appel, Ph.D., - Acting Branch Chief
    Dr. Nathan Appel supervises staff responsible for coordinating the Division's contract- and grant-based medications discovery and preclinical safety assessment efforts. He also oversees grant-related issues in medications discovery and activities of the Addiction Treatment Discovery Program, and directs the Division’s Toxicology Program. He also serves as a project officer/scientist on related contracts and grants. Dr. Appel Joined the NIDA Extramural Program in 1999 after 8 years previous experience at the U.S. Food and Drug Administration.
  • Carol Hubner, Ph.D., - Health Scientist Administrator & Associate Director, Addiction Treatment Discovery Program
    Associate Director of the Addiction Treatment Discovery Program. Project Officer on rodent behavioral pharmacology contracts supporting this program. Seven years of preclinical research experience studying drugs of abuse (primarily cocaine) at the Scripps Clinic and Research Foundation, University of Maryland, and the National Institute of Mental Health. Joined DTMC in 1992.
  • Matthew A. Seager, Ph.D., - Health Scientist Administrator
    Serves as Project Officer on in vitro receptor profiling and safety/discovery pharmacology contracts and supports the Addiction Treatment Discovery Program (ATDP) and the Toxicology Program.  Twelve years of previous experience in preclinical neuroscience drug discovery at Eli Lilly, Merck, and Bristol Myers Squibb. Joined DTMC in 2020.
  • E. Andrew Townsend, Ph.D., - Health Scientist Administrator
    Supports behavioral pharmacology efforts of the Addiction Treatment Discovery Program (ATDP). Ten years of experience in developing and implementing preclinical drug self-administration procedures to evaluate candidate medications for substance use disorders within the Department of Psychiatry at the University of Mississippi Medical Center and the Department of Pharmacology and Toxicology at Virginia Commonwealth University School of Medicine. Joined DTMC in 2022.
  • David A. White, Ph.D., - Health Scientist Administrator & Director, Addiction Treatment Discovery Program
    Serves as Director of the Addiction Treatment Discovery Program Team and is a Project Officer on related contracts. Serves as a NIDA representative to the Interagency Committee on Drug Control (ICDC). More than six years of previous research experience in the area of drug abuse at Emory University's School of Medicine in the Department of Pharmacology. Joined DTMC in 2006.