Nafcillin Sodium

Treats infections caused by penicillinase-producing staphylococci. Sold as Unipen, Unipen In Plastic Container, Nallpen In Plastic Container. Every FDA application for this active ingredient: 5 branded and 19 generic.

As of Nov 15, 2026, FDA lists 24 applications for Nafcillin Sodium (sold as Unipen, Unipen In Plastic Container, Nallpen In Plastic Container), first approved Oct 11, 1965, with 1 new use approved and 0 published complete response letters.

First approved: Oct 11, 1965
Applications: 24
New uses approved: 1
Complete response letters: 0
Medicare spending, 2025: $2.5M

Medicare Spending

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


Nafcillin Sodium	Part D	$2.5M	-9%	866
NAFCILLIN SODIUM	Part B	$34K	New	0

Clinical Trials

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


Combination Antibiotic Therapy for Staphylococcus Aureus BacteremiaStaphylococcus Aureus Bacteremia · Intermountain Health Care, Inc.	Phase 4	Recruiting	Jan 29, 2026
Cefazolin Versus Antistaphylococcal Penicillins for Methicillin Susceptible Staphylococcus Aureus BacteremiaBacteriemia, Methicillin Susceptible Staphylococcus Aureus (MSSA) Infection · Central Hospital, Nancy, France	—	Active, not recruiting	Sep 22, 2025
Does Staphylococcus Aureus Bacteremia Early Dual Therapy Improve Outcomes?Staphylococcus Aureus Bacteremia · West Virginia University	Phase 4	Enrolling by invitation	Aug 29, 2025
Prophylactic Antibiotics Useful With Antibiotic Impregnated External Ventricular Drains (EVDs)?Subarachnoid Hemorrhage, Intracerebral Hemorrhage · Montefiore Medical Center	Phase 1	Recruiting	Aug 12, 2021

Applications

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


Oct 11, 1965	UnipenNDA 50199	Wyeth Ayerst	26	Discontinued
Apr 7, 1970	UnipenNDA 50111	Wyeth Ayerst	27	Discontinued
Jun 23, 1970	Unipen, Unipen In Plastic ContainerNDA 50320	Wyeth Ayerst	62	Discontinued
Oct 16, 1973	UnipenNDA 50462 · New dosage form	Wyeth Ayerst	19	Discontinued
Aug 2, 1984	Nafcillin SodiumANDA 62527	Sandoz	8	Discontinued
Dec 19, 1986	NallpenANDA 62755	Glaxosmithkline	1	Discontinued
Dec 23, 1986	Nafcillin SodiumANDA 62732	Sandoz	9	Discontinued
Sep 29, 1988	Nafcillin SodiumANDA 63008	Chartwell Rx	13	Discontinued
Oct 26, 1988	Nafcillin SodiumANDA 62844	Chartwell Rx	13	Discontinued
Oct 31, 1989	Nallpen In Plastic ContainerNDA 50655 · New dosage form	Baxter Hlthcare	16	Marketed
Apr 20, 2011	Nafcillin SodiumANDA 90005	Istituto Bio Ita Spa	5	Marketed
Jun 30, 2011	Nafcillin SodiumANDA 90002	Acs Dobfar Spa	1	Marketed
Oct 3, 2011	Nafcillin SodiumANDA 90560	Antibiotice	3	Marketed
Aug 24, 2012	Nafcillin SodiumANDA 90580	Sagent Pharms	4	Marketed
Aug 24, 2012	Nafcillin SodiumANDA 90582	Sagent Pharms	3	Marketed
Dec 26, 2012	Nafcillin SodiumANDA 91613	Eugia Pharma Speclts	3	Marketed
Dec 26, 2012	Nafcillin SodiumANDA 91614	Eugia Pharma Speclts	0	Marketed
Apr 7, 2014	Nafcillin SodiumANDA 200002	Onesource Specialty	0	Marketed
Dec 10, 2019	Nafcillin SodiumANDA 206682	Fresenius	0	Discontinued
Jun 2, 2020	Nafcillin SodiumANDA 206761	Fresenius	0	Discontinued
Sep 25, 2026	Nafcillin SodiumANDA 203830	Steriscience	0	Marketed
—	Nafcillin SodiumANDA 61984	Apothecon	0	Discontinued
—	NallpenANDA 61999	Glaxosmithkline	0	Discontinued
—	UnipenANDA 62717	Wyeth Ayerst	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