Didrex

NDA 12427, held by Pfizer. Benzphetamine Hydrochloride.

As of Nov 13, 2026, NDA 12427 (Didrex), held by Pfizer, was first approved by FDA on Oct 26, 1960, with 8 approved supplements and 0 published complete response letters.

First approved: Oct 26, 1960
Review: Standard
Supplements approved: 8
Complete response letters: 0

Approvals and New Uses

The original application and every efficacy supplement, newest first; all 9 submissions below

Date	Submission	Status	Documents
Oct 26, 1960	Original applicationNew molecular entity · Standard review	Approved	None posted

Products

2 strengths and forms


Didrex50MG Federal Register determination that product was not discontinued or withdrawn for safety or effectiveness reasons · tablet;oral	Benzphetamine Hydrochloride	DiscontinuedReference drug
Didrex25MG Federal Register determination that product was not discontinued or withdrawn for safety or effectiveness reasons · tablet;oral	Benzphetamine Hydrochloride	DiscontinuedReference drug

All 9 submissions, including labeling and manufacturing supplements


Apr 8, 2020	Supplement 31Labeling · Standard review	Approved	Label Letter
Feb 5, 2010	Supplement 26Labeling	Approved	Letter Label
Jul 28, 2000	Supplement 21Labeling	Approved	None posted
Jul 27, 2000	Supplement 20Labeling	Approved	None posted
Sep 23, 1998	Supplement 23Manufacturing · Standard review	Approved	None posted
Jul 31, 1992	Supplement 22Manufacturing · Standard review	Approved	None posted
Dec 31, 1985	Supplement 19Labeling	Approved	None posted
Sep 4, 1984	Supplement 18Labeling	Approved	None posted
Oct 26, 1960	Original applicationNew molecular entity · Standard review	Approved	None posted

Identifiers

Application: NDA 12427
Drugs@FDA: Overview at FDA
Company: Pfizer

Approvals, supplements, products and documents come from FDA's Drugs@FDA data files, refreshed daily; Drugs@FDA lists approved applications only. Complete response letters are FDA's published letters. Drugs@FDA and FDA complete response letters