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  5. Drug Efficacy Study Implementation (DESI)
  1. Enforcement Activities | FDA

Drug Efficacy Study Implementation (DESI)

FDA’s administrative process to consider the effectiveness of drugs that had been approved only for safety between 1938 and 1962 is called the drug efficacy study implementation (DESI).

Congress amended the Federal Food, Drug, and Cosmetic Act in 1962 to require that new drugs be shown effective, as well as safe, to obtain FDA approval. The amendment required FDA to evaluate the effectiveness of the drugs the agency had approved only for safety between 1938, when Congress enacted the FD&C Act requiring new drugs be shown safe prior to marketing, and 1962.

Evaluation Procedure

FDA contracted with the National Academy of Sciences/National Research Council (NAS/NRC) to make an initial evaluation of the effectiveness of more than 3,400 drugs that had been approved only for safety between 1938 and 1962. The agency reviewed and reevaluated the NAS/NRC reports and published its initial findings in Federal Register notices.

DESI covered the drugs reviewed by NAS/NRC, as well as the even larger number of drugs that entered the market—without FDA approval—as identical, related or similar to those covered by safety-only FDA approvals.

Final DESI Determinations

FDA’s final DESI determination classifies a drug as either effective for one or more of its labeled indications or lacking substantial evidence of effectiveness for one or more of its labeled indications. Most DESI proceedings have been closed and FDA’s findings have been published in the Federal Register.

  • If FDA’s final DESI determination classifies the drug as effective for one or more of its labeled indications, the product can be marketed for those indications, provided it is the subject of an application approved by FDA for safety and effectiveness. Medicines with a new drug application (NDA) approved before 1962 only for safety require an approved supplement to the original application if found to be effective under DESI. Drugs marketed as identical, related or similar to a DESI drug that FDA classified as effective require either an approved NDA or abbreviated new drug application (ANDA), as appropriate, to be marketed. After FDA approves the application, the drug’s regulatory status is the same as any other drugs approved by FDA for safety and efficacy and is no longer considered part of DESI.
  • If FDA’s final DESI determination classifies a drug as lacking substantial evidence of effectiveness, the agency will provide notice of an opportunity for a hearing. The agency considers these requests and either grants or denies it. If a hearing request is denied or if no hearing is requested, FDA publishes its final determination in the Federal Register withdrawing FDA approval due to lacking substantial evidence of effectiveness. Drugs classified as lacking substantial evidence of effectiveness and those identical, related or similar to it can no longer be marketed and are subject to enforcement action as unapproved new drugs.

The New Drugs, Reports of Information for Drug Effectiveness Federal Register notice (July 9, 1966) provides historical information.

Recent Final Decisions (updated April 2022)

DESI number

Title

Docket

Final agency decision

DESI 10837 Oral Prescription Drugs Containing an Anticholinergic or Antispasmodic in Combination with a Sedative, and Single-Entity Antispasmodic Drug Products, in Oral Dosage Form FDA-1975-N-0336
(Formerly 75N-0184
87 Federal Register 24311
(April 25, 2022)
DESI 7663 Potassium Aminobenzoate Oral Preparations FDA–1977–N–0015 (Formerly 77N–0187) 87 Federal Register 13294 (March 9, 2022)
DESI 10367

Iodochlorhydroxyquin and Hydrocortisone, Vioform HC

FDA-1980-N-0038
(formerly 80N-0012)

85 Federal Register 42877 (July 15, 2020)

DESI 6403

Peripheral Vasodilators, Vasodilan (Isoxsuprine)

FDA-1984-N-0259
(formerly 84N-0167)
85 Federal Register 42882 (July 15, 2020)
(Part of) DESI 1786 Pentaerythritol Tetranitrate (PETN)

FDA-2020-N-1253

(formerly FDA-1987-N-0054;
formerly 87N-0262)

85 Federal Register 42002 (July 13, 2020)

 Open DESI Proceedings

A few DESI proceedings remain open without a final decision or resolution. It is the agency’s policy that drugs subject to an open DESI proceeding may remain on the market during the proceedings.

DESI number

Title

Docket

(Part of) DESI 597

Anticholinergic/Barbiturate Combinations (Donnatal)

FDA-1975-N-0336
(formerly 79N-0184)

(Part of) DESI 597

Donnatal Extentabs

FDA-1975-N-0337
(formerly 75N-0223)

(Part of) DESI 1786

Oral Nitroglycerin, Extended Release

FDA-1977-N-0356
(formerly 75N-0240)

DESI 5378

Amphetamines

FDA-1979-N-0328
(formerly 79N-0190)

DESI 7661

Estrogen-Androgen Fixed-Combination Drug Products; Syntest D.S. and Syntest H.S. tablets

FDA-1998-P-0083
(formerly 76N-0377)

DESI 8076

Benzocaine, Butyl Aminobenzoate (Butamben), and Tetracaine Hydrochloride Fixed Combination Drug Product; Cetacaine

FDA-1975-N-0338
(formerly 75N-0203)

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