Sulfasalazine

Treats mild to moderate ulcerative colitis. Sold as Azulfidine, Azulfidine En-Tabs. Every FDA application for this active ingredient: 4 branded and 12 generic.

As of Nov 15, 2026, FDA lists 16 applications for Sulfasalazine (sold as Azulfidine, Azulfidine En-Tabs), first approved Jun 20, 1950, with 0 new uses approved and 0 published complete response letters.

First approved: Jun 20, 1950
Applications: 16
New uses approved: 0
Complete response letters: 0
Medicare spending, 2025: $21.3M

Medicare Spending

CMS Part D and Part B, 2025, before manufacturer rebates; matched by generic name


Sulfasalazine	Part D	$14.2M	+14%	110,911
Sulfasalazine Dr	Part D	$6.9M	+17%	40,703
Azulfidine	Part D	$203K	-13%	139

What Pharmacies Pay

Median price per unit across package codes in CMS's weekly NADAC survey, Nov 11, 2026, before rebates; see every drug's price change

SULFASALAZINE 500 MG TABLET: $0.198 per unitGeneric · +9% in a year
SULFASALAZINE DR 500 MG TAB: $0.289 per unitGeneric · +13% in a year

Clinical Trials

19 open or ongoing studies name this ingredient as an intervention, including as a comparator; newest first. See all


Clinical Efficacy of Telitacicept in Sjögren's Disease With Interstitial Lung DiseaseSjögren's Disease, Interstitial Lung Disease · Peking University People's Hospital	—	Recruiting	Sep 28, 2026
The Effect of Nicorandil on Rheumatoid Arthritis PatientsRheumatoid Arthritis (RA) · Ain Shams University	Phase 2 / Phase 3	Recruiting	Jul 28, 2026
Study of ECC4703 With Sulfasalazine and PitavastatinNon-alcoholic Fatty Liver Disease (NAFLD), Dyslipidaemia · Eccogene	Phase 1	Recruiting	Jul 24, 2026
Venlafaxine as Adjunct Therapy in Rheumatoid ArthritisRheumatoid Arthritis · Ain Shams University	Phase 2	Not yet recruiting	Mar 27, 2026
Validation of Hemoglobin A1c in Patients With Inflammatory Arthritis Treated With SulfasalazineInflammatory Arthritis, Diabetes (DM) · Klavs Würgler Hansen	—	Recruiting	Feb 18, 2026
Recombinant Herpes Zoster Vaccine in Patients With Autoimmune Rheumatic Diseases Under ImmunomodulatorsAutoimmune Rheumatic Diseases · University of Sao Paulo General Hospital	Phase 4	Recruiting	Dec 12, 2025
Immunosuppressant Management in Rheumatology Patients Undergoing Elective Total Shoulder ArthroplastyRheumatic Disease · NYU Langone Health	Phase 2	Recruiting	Aug 24, 2025
"Effect of Vitamin E (α-Tocopherol) on Clinical Activity and Inflammation in Rheumatoid Arthritis"Rheumatoid Arthritis · University of Guadalajara	Phase 2 / Phase 3	Recruiting	Apr 8, 2025

Applications

NDAs, BLAs and generic ANDAs for this ingredient, oldest first; each opens its full history


Jun 20, 1950	Azulfidine, Azulfidine En-TabsNDA 7073 · New molecular entity	Pfizer	64	Marketed
Nov 12, 1973	SulfasalazineANDA 80197	Chartwell	14	Marketed
Apr 9, 1974	S.A.S.-500ANDA 83450	Solvay	0	Discontinued
May 12, 1976	SulfasalazineANDA 84964	Watson Labs	0	Discontinued
Oct 21, 1977	SulfasalazineANDA 85828	Watson Labs	28	Marketed
Dec 29, 1980	AzulfidineNDA 18605 · New dosage form	Pharmacia And Upjohn	4	Discontinued
Apr 2, 1981	SulfasalazineANDA 87197	Watson Labs	6	Discontinued
Oct 19, 1987	SulfasalazineANDA 89590	Sun Pharm Industries	24	Discontinued
Sep 16, 1994	SulfasalazineANDA 86184	Epic Pharma LLC	5	Discontinued
Oct 17, 1996	AzulfidineNDA 20465 · TYPE 6	Pharmacia And Upjohn	0	Marketed
Aug 18, 2000	Azulfidine En-TabsNDA 21243 · TYPE 6	Pharmacia Upjohn	0	Marketed
Jan 11, 2002	SulfasalazineANDA 40349	Nuvo Pharms Inc	5	Marketed
Jan 11, 2002	SulfasalazineANDA 75339	Nuvo Pharms Inc	6	Marketed
Nov 4, 2025	SulfasalazineANDA 219046	Rising	0	Marketed
—	SulfasalazineANDA 88052	Watson Labs	0	Discontinued
—	SulfasalazineANDA 89339	Superpharm	0	Discontinued

Applications, approvals and products come from FDA's Drugs@FDA data files, refreshed weekly, grouped by active ingredient as FDA spells it. Complete response letters are FDA's published letters. Medicare spending is CMS's Part D and Part B dashboard, matched to this ingredient by generic name; shortages are FDA's shortage list, matched by application number; clinical trials are ClinicalTrials.gov studies naming the ingredient as an intervention, refreshed daily; safety programs are FDA's REMS list, matched by application number or, for shared programs, by ingredient. Drugs@FDA