Cyclapen-W

NDA 50508, held by Wyeth Ayerst. Cyclacillin.

As of Nov 13, 2026, NDA 50508 (Cyclapen-W), held by Wyeth Ayerst, was first approved by FDA on Sep 14, 1979, with 15 approved supplements and 0 published complete response letters.

First approved: Sep 14, 1979
Review: Standard
Supplements approved: 15
Complete response letters: 0

Approvals and New Uses

The original application and every efficacy supplement, newest first; all 16 submissions below

Date	Submission	Status	Documents
Sep 14, 1979	Original applicationNew molecular entity · Standard review	Approved	None posted

Products

3 strengths and forms

Product	Active ingredient	Marketing
Cyclapen-W125MG/5ML · for suspension;oral	Cyclacillin	Discontinued
Cyclapen-W250MG/5ML · for suspension;oral	Cyclacillin	Discontinued
Cyclapen-W500MG/5ML · for suspension;oral	Cyclacillin	Discontinued

All 16 submissions, including labeling and manufacturing supplements

Date	Submission	Status	Documents
Aug 12, 1985	Supplement 3Labeling · Standard review	Approved	None posted
Sep 24, 1984	Supplement 2Manufacturing · Standard review	Approved	None posted
Feb 13, 1984	Supplement 1Manufacturing · Standard review	Approved	None posted
Aug 17, 1982	Supplement 15Manufacturing · Standard review	Approved	None posted
Aug 4, 1982	Supplement 14Labeling · Standard review	Approved	None posted
Jul 8, 1982	Supplement 13Manufacturing · Standard review	Approved	None posted
May 27, 1982	Supplement 12Labeling · Standard review	Approved	None posted
Mar 8, 1982	Supplement 11Labeling · Standard review	Approved	None posted
Mar 8, 1982	Supplement 9Labeling · Standard review	Approved	None posted
Feb 4, 1982	Supplement 10Manufacturing · Standard review	Approved	None posted
Nov 28, 1980	Supplement 8Labeling · Standard review	Approved	None posted
Sep 25, 1980	Supplement 7Labeling · Standard review	Approved	None posted
Apr 22, 1980	Supplement 6Manufacturing · Standard review	Approved	None posted
Oct 30, 1979	Supplement 5Manufacturing · Standard review	Approved	None posted
Sep 19, 1979	Supplement 4Labeling · Standard review	Approved	None posted
Sep 14, 1979	Original applicationNew molecular entity · Standard review	Approved	None posted

Identifiers

Application: NDA 50508
Drugs@FDA: Overview at FDA
Company: Wyeth-Ayerst

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