Arimidex

Treats postmenopausal women with hormone receptor-positive early breast cancer. NDA 20541, held by Ani Pharms. Anastrozole.

As of Nov 14, 2026, NDA 20541 (Arimidex), held by Ani Pharms, was first approved by FDA on Dec 27, 1995, with 22 approved supplements and 0 published complete response letters.

First approved: Dec 27, 1995
Review: Standard
Supplements approved: 22
Complete response letters: 0

What It's For

From the FDA-approved label (Indications and Usage)

ARIMIDEX is an aromatase inhibitor indicated for:

Adjuvant treatment of postmenopausal women with hormone receptor-positive early breast cancer
First-line treatment of postmenopausal women with hormone receptor-positive or hormone receptor-unknown locally advanced or metastatic breast cancer
Treatment of advanced breast cancer in postmenopausal women with disease progression following tamoxifen therapy. Patients with ER-negative disease and patients who did not respond to previous tamoxifen therapy rarely responded to ARIMIDEX 1.1 Adjuvant Treatment ARIMIDEX is indicated for adjuvant treatment of postmenopausal women with hormone receptor-positive early breast cancer. 1.

Full prescribing information on DailyMed ↗

Approvals and New Uses

The original application and every efficacy supplement, newest first; all 23 submissions below


Apr 18, 2011	Supplement 26Efficacy (new indication or use) · Standard review	Approved	Letter Label
Apr 30, 2009	Supplement 24Efficacy (new indication or use)	Approved	Label Letter
Sep 16, 2005	Supplement 16Efficacy (new indication or use)	Approved	Letter Label
Sep 5, 2002	Supplement 10Efficacy (new indication or use) · Priority review	Approved	Review Label Letter
Sep 1, 2000	Supplement 6Efficacy (new indication or use) · Standard review	Approved	Review Letter Label
Dec 27, 1995	Original applicationNew molecular entity · Standard review	Approved	Review

Products

1 strengths and forms

Product	Active ingredient	Marketing
Arimidex1MG · tablet;oral	Anastrozole	RxReference drug

All 23 submissions, including labeling and manufacturing supplements


Dec 16, 2024	Supplement 36Labeling · Standard review	Approved	Letter Label
Dec 13, 2018	Supplement 31Labeling · Standard review	Approved	Label Letter
May 2, 2014	Supplement 29Labeling	Approved	Letter Label
May 1, 2013	Supplement 27Labeling · Standard review	Approved	Review Label Letter
Apr 18, 2011	Supplement 26Efficacy (new indication or use) · Standard review	Approved	Letter Label
Apr 30, 2009	Supplement 25Labeling · Standard review	Approved	Label Letter
Apr 30, 2009	Supplement 24Efficacy (new indication or use)	Approved	Label Letter
Dec 10, 2008	Supplement 23Labeling · Standard review	Approved	Review Label Letter
Dec 10, 2008	Supplement 21Labeling · Standard review	Approved	Review Label
Dec 10, 2008	Supplement 20Labeling · Standard review	Approved	Review Label Letter
May 10, 2006	Supplement 18Manufacturing	Approved	None posted
Sep 16, 2005	Supplement 16Efficacy (new indication or use)	Approved	Letter Label
Aug 30, 2004	Supplement 15Labeling · Standard review	Approved	Letter Label
Oct 7, 2002	Supplement 5Labeling · Standard review	Approved	Letter
Sep 5, 2002	Supplement 10Efficacy (new indication or use) · Priority review	Approved	Review Label Letter
Sep 10, 2001	Supplement 8Manufacturing · Standard review	Approved	None posted
Aug 2, 2001	Supplement 7Manufacturing · Standard review	Approved	None posted
Sep 1, 2000	Supplement 6Efficacy (new indication or use) · Standard review	Approved	Review Letter Label
Aug 13, 1998	Supplement 4Manufacturing · Standard review	Approved	None posted
Feb 6, 1998	Supplement 2Labeling · Standard review	Approved	None posted
Sep 19, 1997	Supplement 3Labeling · Standard review	Approved	None posted
Oct 18, 1996	Supplement 1Labeling · Standard review	Approved	None posted
Dec 27, 1995	Original applicationNew molecular entity · Standard review	Approved	Review

Identifiers

Application: NDA 20541
Drugs@FDA: Overview at FDA
Company: ANI Pharmaceuticals

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