Product-Specific Guidances for Generic Drug Development

Disclaimer: Due to April 2019 systemwide upgrades to, the filenames for product-specific guidances on this web page may not match the corresponding guidance titles. In such cases, the name on the document correctly identifies the title of the guidance. These discrepancies will be corrected as soon as possible.

To successfully develop and manufacture a generic drug product, an applicant should consider that their product is expected to be: pharmaceutically equivalent to its reference listed drug (RLD), i.e., to have the same active ingredient, dosage form, strength, and route of administration under the same conditions of use; bioequivalent to the RLD, i.e., to show no significant difference in the rate and extent of absorption of the active pharmaceutical ingredient; and, consequently, therapeutically equivalent, i.e., to be substitutable for the RLD with the expectation that the generic product will have the same safety and efficacy as its reference listed drug.

According to 21 CFR 320.24, different types of evidence may be used to establish bioequivalence for pharmaceutically equivalent drug products, including in vivo or in vitro testing, or both. The selection of the method used to demonstrate bioequivalence depends upon the purpose of the study, the analytical methods available, and the nature of the drug product. Under this regulation, applicants must conduct bioequivalence testing using the most accurate, sensitive, and reproducible approach available among those set forth in 21 CFR 320.24. As the initial step for selecting methodology for generic drug product development, applicants are referred to the following draft guidance: Draft Guidance for Industry on Bioequivalence Studies With Pharmacokinetic Endpoints for Drugs Submitted Under an Abbreviated New Drug Application (ANDA) (August 2021).

To further facilitate generic drug product availability and to assist the generic pharmaceutical industry with identifying the most appropriate methodology for developing drugs and generating evidence needed to support ANDA approval, FDA publishes product-specific guidances describing the Agency's current thinking and expectations on how to develop generic drug products therapeutically equivalent to specific reference listed drugs.

FDA publishes these product-specific guidances to foster drug product development, and ANDA submission and approval, ultimately providing increased access to safe, affordable generic drugs.

These guidances are published in an incremental manner and listed below in alphabetical order according to the active ingredient's name. The most recently published guidances (new and revised) are listed below.

Additionally, as part of FDA's commitments under the Generic Drug User Fee Amendments Reauthorization of 2017 (GDUFA II), FDA will publish guidances for reference listed drugs that are (1) new chemical entities and (2) approved on or after October 1, 2017, at least 2 years prior to the earliest lawful ANDA filing date. 1 This goal does not include complex products as defined in the GDUFA II Commitment Letter. FDA will strive to issue guidance for a complex product as soon as scientific recommendations are available.

In addition to the provided information, sponsors and investigators of any Investigational New Drug (IND)-exempt pharmacokinetic (PK) studies, pharmacodynamic (PD) studies, or bioequivalence (BE) and/or bioavailability (BA) studies involving human subjects in support of an ANDA should refer to the current RLD labeling, including BOXED WARNINGS, CONTRAINDICATIONS, WARNINGS AND PRECAUTIONS and ADVERSE REACTIONS sections. This information should be considered during study design and conduct; including attention to appropriate subject screening and selection, inclusion and exclusion criteria, and appropriate clinical safety monitoring.

Some of the product-specific guidances include discussion regarding data formats. Please note that under section 745A(a) of the Federal Food, Drug, and Cosmetic Act, separate Agency-wide guidances specify the electronic formats, subject matter, and scope of applicability for certain submissions, including submissions to ANDAs. As these are finalized guidances and subject to described timetables for implementation, these guidances are binding and the electronic format(s) specified must be used for submissions to ANDAs. Questions and general information regarding the preparation of submissions in electronic format may be directed to CDER at Questions regarding submission of datasets to CDER may be sent to

COMMENTS: The Agency is seeking feedback and considers comments to the docket on these guidances. You may submit comments on any guidance at any time as follows: Submit electronic comments to Docket FDA-2007-D-0369. For further information on submitting electronic comments, refer to the website ( You may also mail your written comments to DDM (HFA-305), FDA, 5630 Fishers Lane, Rm. 1061, Rockville, MD 20852. All submissions received must include the Docket No. [FDA-2007-D-0369]. Please contact the Help Desk at 1-877-378-5457 (toll free) for assistance regarding submissions.

The FDA posts plans for issuing new or revised product-specific guidances on the Upcoming Product-Specific Guidances for Complex Generic Drug Product Development web page.

For additional information on development of generic drug products, please refer to FDA’s biopharmaceutics guidances.

1GDUFA Reauthorization Performance Goals and Program Enhancements Fiscal Years 2018-2022 (GDUFA II Commitment Letter)




Total number of currently published PSGs: 1921

Product-Specific Guidances for Specific Products Arranged by Active Ingredient

Search by Active Ingredient or by RLD or RS Number

78 record(s) found for 'N'

Active Ingredient (link to Specific Guidance) URL Type Route Dosage Form RLD or RS Number Date Recommended
Nabilone Draft Oral Capsule 018677 07/2009
Nabumetone Final Oral Tablet 019583 05/2008
Nadolol Final Oral Tablet 018063 10/2011
Naftifine Hydrochloride Draft Topical Cream 1% 019599 03/2012
Naftifine Hydrochloride Draft Topical Gel 019356 03/2012
Naftifine Hydrochloride hydrochloride_topical cream2_RLD 019599_RC01-16.pdf Draft Topical Cream 2% 019599 01/2016
Naftifine Hydrochloride hydrochloride_topical get 2_RLD 204286_RC01-16.pdf Draft Topical Gel 204286 01/2016
Naldemedine Tosylate tosylate_oral tablet_NDA 208854_RC11-17.pdf Draft Oral Tablet 208854 02/2018
Naloxegol Oxalate oxalate_oral tablet_NDA 204760_RV11-17.pdf Draft Oral Tablet 204760 02/2018
Naloxone Hydrochloride hydrochloride_ nasal spray_ NDA 208411_RC04-17.pdf Draft Nasal Spray 208411 04/2017
Naloxone Hydrochloride; Oxycodone Hydrochloride Draft Oral Tablet, Extended Release 205777 11/2020
Naltrexone intramuscular inj. suspension_021897_RV09-15.pdf Draft Intramuscular Suspension, Extended Release 021897 09/2015
Naltrexone Hydrochloride Draft Oral Tablet 018932 076264 12/2009
Naproxen Draft Oral Tablet, Delayed Release 020067 02/2010
Naproxen Draft Oral Tablet 017581 07/2008
Naproxen Oral Suspension NDA 018965 PSG Page RC May 2019.pdf Draft Oral Suspension 018965 05/2019
Naproxen Sodium sodium_Oral capsule_021920_RC06-15.pdf Draft Oral Capsule 021920 06/2015
Naproxen Sodium Draft Oral Tablet, Extended Release 020353 04/2010
Naproxen Sodium Draft Oral Tablet 018164 07/2008
Naproxen Sodium Draft Oral Tablet 020204 07/2008
Naproxen Sodium; Pseudoephedrine Hydrochloride sodium; Pseudoephedrine HCl_oral ER tablet_NDA 021076_RC11-17.pdf Draft Oral Tablet, Extended Release 021076 02/2018
Naproxen Sodium; Sumatriptan Succinate;_Sumatriptan_Succinate_tab_21926_RC08-10.pdf Draft Oral Tablet 021926 08/2010
Naratriptan Hydrochloride Draft Oral Tablet 020763 07/2008
Nateglinide Final Oral Tablet 021204 05/2008
Nebivolol Hydrochloride Draft Oral Tablet 021742 12/2014
Nebivolol hydrochloride; Valsartan HCl; Valsartan_oral tablet_NDA 206302_RC07-18.pdf Draft Oral Tablet 206302 07/2018
Nelfinavir Mesylate Mesylate pwd oral 20778_RC4-06.pdf Draft Oral Suspension 020778 11/2007
Nelfinavir Mesylate Final Oral Tablet 020779 021503 05/2008
Nepafenac suspension 0.1_RLD 021862_RV12-16.pdf Draft Ophthalmic Drops, Suspension 0.1% 021862 12/2016
Nepafenac suspension 0.3_RLD 203491_RV12-16.pdf Draft Ophthalmic Drops, Suspension 0.3% 203491 12/2016
Neratinib maleate Maleat Oral Tablets NDA 208051 RC 09-2018.pdf Draft Oral Tablet 208051 09/2018
Netarsudil dimesylate Dimesylate_Ophthalmic solution drops_NDA 208254_RC Oct 2018.pdf Draft Ophthalmic Drops, Solution 208254 11/2018
Netupitant; Palonosetron Hydrochloride and Palonosetron hydrochloride_oral capsule_205718_RC09-15.pdf Draft Oral Capsule 205718 09/2015
Nevirapine Draft Oral Tablet, Extended Release 201152 07/2014
Nevirapine Final Oral Suspension 020933 05/2008
Nevirapine tablet_RLD 20636_RV03-17.pdf Draft Oral Tablet 020636 05/2017
Niacin Draft Oral Tablet, Extended Release 020381 12/2009
Nicardipine Hydrochloride Draft Oral Capsule, Extended Release 020005 07/2008
Nicotine Draft Transdermal Film, Extended Release 020076 020165 11/2019
Nicotine spray_RLD 020385_RC01-16.pdf Draft Nasal Spray, Metered 020385 01/2016
Nicotine Polacrilex Polacrilex Troche Lozenge NDA 21330 RV 09-2018.pdf Draft Oral Troche/Lozenge 021330 09/2018
Nicotine Polacrilex Polacrilex Buccal Chewing Gum NDA 20066 and NDA 18612 RV 09-2018.pdf Draft Buccal Chewing Gum 018612 020066 09/2018
Nicotine Polacrilex Polacrilex Troche Lozenge (Mini) NDA 022360 RV 09-2018.pdf Draft Oral Lozenge 022360 09/2018
Nifedipine Draft Oral Tablet, Extended Release 020198 09/2012
Nifedipine Draft Oral Capsule 018482 06/2011
Nifedipine Final Oral Tablet, Extended Release 019684 10/2011
Nilotinib Hydrochloride Draft Oral Capsule 022068 07/2014
Nilutamide Final Oral Tablet 020169 10/2011
Nimodipine capsule_NDA 018869_RC07-18.pdf Draft Oral Capsule 018869 07/2018
Nintedanib Esylate esylate_oral capsule_205832_RC09-15.pdf Draft Oral Capsule 205832 09/2015
Niraparib Tosylate tosylate_oral capsule_NDA 208447_RC11-17.pdf Draft Oral Capsule 208447 02/2018
Nisoldipine oral extended release tablet ANDA 079051 RV 09-2018.pdf Draft Oral Tablet, Extended Release 079051 09/2018
Nisoldipine ER tablet_NDA 020356_RV07-18.pdf Draft Oral Tablet, Extended Release 020356 07/2018
Nitazoxanide Draft Oral Tablet 021497 03/2021
Nitazoxanide Draft Oral For Suspension 021498 03/2021
Nitisinone tablet_NDA 209449_RC07-18.pdf Draft Oral Tablet 209449 07/2018
Nitisinone capsule_ NDA021232_RC08-17.pdf Draft Oral Capsule 021232 10/2017
Nitisinone Suspension_RLD 206356_RC12-16.pdf Draft Oral Suspension 206356 12/2016
Nitrofurantoin Draft Oral Suspension 009175 05/2021
Nitrofurantoin Macrocrystalline Draft Oral Capsule 016620 11/2019
Nitrofurantoin; Nitrofurantoin Macrocrystalline Draft Oral Capsule 020064 11/2019
Nitroglycerin powder_RLD 208424_RC03-17.pdf Draft Sublingual Powder 208424 05/2017
Nitroglycerin ointment_087355_RC06-15.pdf Draft Transdermal Ointment 087355 06/2015
Nitroglycerin Draft Sublingual Aerosol, Metered 021780 02/2012
Nitroglycerin Draft Sublingual Tablet 021134 02/2011
Nitroglycerin Draft Oral/Sublingual Spray, Metered 018705 02/2012
Nitroglycerin Draft Transdermal Film, Extended Release 020145 11/2019
Nitroglycerin Draft Transdermal Film, Extended Release 020144 11/2019
Norethindrone Draft Oral Tablet 017060 10/2009
Norethindrone Draft Oral Tablet 016954 04/2009
Norethindrone Acetate Draft Oral Tablet 018405 03/2009
Nortriptyline Hydrochloride HCl_oral capsule_018013_RC09-15.pdf Draft Oral Capsule 018013 09/2015
Nystatin Draft Oral Suspension 062512 11/2010
Nystatin Draft Topical Cream 064022 05/2010
Nystatin Draft Topical Ointment 062124 05/2010
Nystatin Draft Topical Powder 065203 08/2021
Nystatin; Triamcinolone Acetonide; Triamcinolone acetonide_topical cream_ANDA 062364_RC03-17.pdf Draft Topical Cream 062364 05/2017
Nystatin; Triamcinolone Acetonide; Triamcinolone acetonide_topical ointment_ANDA 063305_RC03-17.pdf Draft Topical Ointment 063305 05/2017

Newly Added Guidances since August 2021

Active Ingredient (link to Specific Guidance) URL Type Route Dosage Form RLD or RS Number Date Recommended
Acyclovir Draft Ophthalmic Ointment 202408 08/2021
Albuterol Sulfate; Ipratropium Bromide Draft Inhalation Spray, Metered 021747 08/2021
Amisulpride Draft Intravenous Solution 209510 08/2021
Avapritinib Draft Oral Tablet 212608 08/2021
Carbinoxamine Maleate Draft Oral Tablet 008915 08/2021
Cefiderocol Sulfate Tosylate Draft Intravenous Powder 209445 08/2021
Copper Dotatate Cu-64 Draft Intravenous Solution 213227 08/2021
Esomeprazole Magnesium Draft Oral Tablet, Orally Disintegrating, Delayed Release 214278 08/2021
Estradiol Draft Transdermal Gel, Metered 021166 08/2021
Ethinyl Estradiol; Levonorgestrel Draft Transdermal System 204017 08/2021
Fostemsavir Tromethamine Draft Oral Tablet, Extended Release 212950 08/2021
Indomethacin Draft Rectal Suppository 017814 08/2021
Ipratropium Bromide Draft Nasal Spray, Metered 020393 020394 08/2021
Lasmiditan Succinate Draft Oral Tablet 211280 08/2021
Leuprolide Acetate Draft Subcutaneous Powder 021343 08/2021
Loteprednol Etabonate Draft Ophthalmic Gel 208219 08/2021
Olodaterol Hydrochloride Draft Inhalation Spray, Metered 203108 08/2021
Osilodrostat Phosphate Draft Oral Tablet 212801 08/2021
Ozanimod Hydrochloride Draft Oral Capsule 209899 08/2021
Paliperidone Palmitate Draft Intramuscular Suspension, Extended Release 207946 08/2021
Semaglutide Draft Oral Tablet 213051 08/2021
Sufentanil Citrate Draft Sublingual Tablet 209128 08/2021
Tazemetostat Hydrobromide Draft Oral Tablet 211723 08/2021

Newly Revised Guidances since August 2021

Active Ingredient (link to Specific Guidance) URL Type Route Dosage Form RLD or RS Number Date Recommended
Bexarotene Draft Oral Capsule 021055 08/2021
Budesonide Draft Oral Capsule, Delayed Release 021324 08/2021
Eltrombopag Olamine Draft Oral Tablet 022291 08/2021
Eltrombopag Olamine Draft Oral For Suspension 207027 08/2021
Ferric Citrate Draft Oral Tablet 205874 08/2021
Ferric Oxyhydroxide Draft Oral Tablet, Chewable 205109 09/2021
Ferric Oxyhydroxide Draft Intravenous Injectable 021135 09/2021
Letrozole Draft Oral Tablet 020726 08/2021
Leuprolide Acetate Draft Injection Injectable 019732 020011 020263 08/2021
Leuprolide Acetate Draft Injection Injectable 020517 020708 08/2021
Liothyronine Sodium Draft Oral Tablet 010379 08/2021
Loteprednol Etabonate Draft Ophthalmic Suspension/Drops 020583 08/2021
Nystatin Draft Topical Powder 065203 08/2021
Orlistat Draft Oral Capsule 020766 021887 08/2021
Paclitaxel Draft IV Infusion For Suspension 021660 08/2021
Podofilox Draft Topical Gel 020529 08/2021
Sodium Zirconium Cyclosilicate Draft Oral For Suspension 207078 08/2021
Tazarotene Draft Topical Cream 0.05% 021184 08/2021

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