U.S. flag An official website of the United States government

U.S. Food and Drug Administration
  1. Home
  2. Drug Databases
  3. PSG Database

Product-Specific Guidances for Generic Drug Development

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 RLD.

According to 21 CFR 320.24, different types of evidence may be used to establish bioequivalence (BE) for pharmaceutically equivalent drug products, including in vivo or in vitro testing, or both. The selection of the method used to demonstrate BE depends upon the purpose of the study, the analytical methods available, and the nature of the drug product. Under this regulation, applicants must conduct BE 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initial step for selecting methodology for generic drug product development, applicants are referred to the following draft guidance: Draft Guidance for Industry on Bioequivalence Studies With Pharmacokinetic Endpoints for Drugs Submitted Under an Abbreviated New Drug Application (ANDA) (August 2021).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 facilitate generic drug product availability and further assist the generic pharmaceutical industry with identifying the most appropriate methodology for developing drugs and generating evidence needed to support ANDA approval, the FDA publishes product-specific guidances (PSG). PSGs describe the Agency's current thinking and expectations to develop generic drug products therapeutically equivalent to specific RLDs.

The FDA publishes PSGs to foster drug product development, ANDA submission and approval, and ultimately provide increased access to generic drugs.

PSGs 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.

The implementation of FDA's commitments under the Generic Drug User Fee Amendments Reauthorization of 20221 (GDUFA III). with regard to issuance of PSGs is effective on October 1, 2022. Under GDUFA III, the FDA will issue PSGs consistent with the following goals:

  • For complex products1,2 approved in new drug applications (NDAs) on or after October 1, 2022, a PSG will be issued for 50 percent of such NDA products within two years after the date of approval, and for 75 percent of such NDA products within three years after the date of approval.
  • FDA will continue to develop PSGs for complex products approved prior to October 1, 2022, for which no PSG has been published.
  • For non-complex drug products approved in NDAs on or after October 1, 2022, that contain a new chemical entity (NCE) (as described in section 505(j)(5)(F)(ii) of the FD&C Act), a PSG will be issued within two years after the date of approval for 90 percent of such products.
In addition to GDUFA III PSG goals, the FDA considers several factors when prioritizing PSG development. The FDA evaluates the generic industries and other stakeholders' interest in products that do not have a PSG through controlled correspondences, public requests, and pre-ANDA meeting requests.

The FDA also evaluates drug availability and accessibility and considers public health priorities, including but not limited to, public health emergencies and drug safety and efficacy updates. In addition to these elements, the FDA continually assesses the status and outcomes of ongoing GDUFA research to ensure there are sufficient and adequate data and evidence to support the development of PSGs that align with the FDA's current scientific thinking.

Sponsors and investigators of any investigational new drug (IND)-exempt pharmacokinetic (PK) studies, pharmacodynamic (PD) studies, or 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.

In addition to the provided information, sponsors and investigators of any Investigational New Drug (IND)-exempt pharmacokinetic (PK) studies, pharmacodynamic (PD) studies, or 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 PSGs 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 esub@fda.hhs.gov. Questions regarding submission of datasets to CDER may be sent to edata@fda.hhs.gov.

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 (www.regulations.gov). 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 Regulations.gov Help Desk at 1-877-378-5457 (toll free) or at (www.regulations.gov/support) for assistance regarding submissions.

The FDA posts plans for issuing new or revised PSGs on the Upcoming Product-Specific Guidances for Generic Drug Product Development web page

For additional information on development of generic drug products, please refer to FDA's guidance document database.

1GDUFA Reauthorization Performance Goals and Program Enhancements Fiscal Years 2023-2027 (GDUFA III Commitment Letter)

2Classifying Approved New Drug Products and Drug-device combination Products as Complex Products for Generic Drug Development Purposes (CDER MAPP 5240.10)

Total number of currently published PSGs: 2288

Product-Specific Guidances for Specific Products Arranged by Active Ingredient

Search by Active Ingredient or by RLD or RS Number

Newly Added Guidances since May 20, 2025

Active Ingredient (link to Specific Guidance) URL Type Route Dosage Form RLD or RS Number Date Recommended
Albuterol Sulfate; Budesonide https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_214070.pdf Draft Inhalation Aerosol, Metered 214070 05/20/2025
Benzgalantamine Gluconate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_218549.pdf Draft Oral Tablet, Delayed Release 218549 05/20/2025
Brimonidine Tartrate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_218424.pdf Draft Ophthalmic Solution/Drops 218424 05/20/2025
Budesonide; Formoterol Fumarate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_216579.pdf Draft Inhalation Aerosol, Metered 216579 05/20/2025
Carbinoxamine Maleate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_008955-ODT.pdf Draft Oral Tablet, Orally Disintegrating 008955 05/20/2025
Ceftobiprole Medocaril Sodium https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_218275.pdf Draft Intravenous Powder 218275 05/20/2025
Clobetasol Propionate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_218158.pdf Draft Ophthalmic Suspension/Drops 218158 05/20/2025
Clonidine Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_217645.pdf Draft Oral Suspension, Extended Release 217645 05/20/2025
Diazepam https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_218623.pdf Draft Buccal Film 218623 05/20/2025
Epinephrine https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_214697.pdf Draft Nasal Spray 214697 05/20/2025
Epinephrine https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_215875.pdf Draft Intravenous Solution 215875 05/20/2025
Etrasimod Arginine https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_216956.pdf Draft Oral Tablet 216956 05/20/2025
Fluticasone Propionate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_209022.pdf Draft Nasal Spray, Metered 209022 05/20/2025
Gepirone Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_021164.pdf Draft Oral Tablet, Extended Release 021164 05/20/2025
Iptacopan Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_218276.pdf Draft Oral Capsule 218276 05/20/2025
Levoketoconazole https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_214133.pdf Draft Oral Tablet 214133 05/20/2025
Levonorgestrel https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_208224.pdf Draft Intrauterine Intrauterine Device 208224 05/20/2025
Melphalan Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_201848.pdf Draft Intra-arterial Powder 201848 05/20/2025
Metformin Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_020357-TabC.pdf Draft Oral Tablet, Chewable 020357 05/20/2025
Momelotinib Dihydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_216873.pdf Draft Oral Tablets 216873 05/20/2025
Motixafortide Acetate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_217159.pdf Draft Subcutaneous Powder 217159 05/20/2025
Norgestrel https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_017031.pdf Draft Oral Tablet 017031 05/20/2025
Paclitaxel https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_211875.pdf Draft Intravenous Powder 211875 05/20/2025
Pemetrexed Disodium https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_214218.pdf Draft Intravenous Solution 214218 05/20/2025
Pemetrexed Ditromethamine https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_208746.pdf Draft Intravenous Powder 208746 05/20/2025
Pilocarpine Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_217836.pdf Draft Ophthalmic Solution 217836 05/20/2025
Repotrectinib https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_218213.pdf Draft Oral Capsule 218213 05/20/2025
Risperidone https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_214835.pdf Draft Intramuscular For Suspension, Extended Release 214835 05/20/2025
Roflumilast https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_215985.pdf Draft Topical Cream 215985 05/20/2025
Selenium Sulfide https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_007936.pdf Draft Topical Lotion/Shampoo 007936 05/20/2025
Terbinafine https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_021958.pdf Draft Topical Gel 021958 05/20/2025
Terbinafine Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_021124.pdf Draft Topical Solution, Spray 021124 05/20/2025
Vamorolone https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_215239.pdf Draft Oral Suspension 215239 05/20/2025
Zilucoplan Sodium https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_216834.pdf Draft Subcutaneous Solution 216834 05/20/2025
Zonisamide https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_214273.pdf Draft Oral Suspension 214273 05/20/2025
Zuranolone https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_217369.pdf Draft Oral Capsule 217369 05/20/2025

Newly Revised Guidances since May 20, 2025

Active Ingredient (link to Specific Guidance) URL Type Route Dosage Form RLD or RS Number Date Recommended
Aripiprazole https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_202971.pdf Draft Intramuscular For Suspension, Extended Release 202971 05/20/2025
Celecoxib https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_020998.pdf Draft Oral Capsule 020998 05/20/2025
Daridorexant Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_214985.pdf Draft Oral Tablet 214985 05/20/2025
Deutetrabenazine https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_216354.pdf Draft Oral Tablet, Extended Release 216354 05/20/2025
Epinephrine https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_205920.pdf Draft Inhalation Aerosol, Metered 205920 05/20/2025
Ertugliflozin https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_209803.pdf Draft Oral Tablet 209803 05/20/2025
Loratadine https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_021952.pdf Draft Oral Capsule 021952 05/20/2025
Migalastat Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_208623.pdf Draft Oral Capsule 208623 05/20/2025
Terbinafine Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_020980.pdf Draft Topical Cream 020980 05/20/2025
Thalidomide https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_020785.pdf Draft Oral Capsule 020785 05/20/2025
Tipiracil Hydrochloride; Trifluridine https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_207981.pdf Draft Oral Tablet 207981 05/20/2025
Tizanidine Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_021447.pdf Draft Oral Capsule 021447 05/20/2025
Trientine Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_019194.pdf Draft Oral Capsule 019194 05/20/2025
Verapamil Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_018593.pdf Draft Oral Tablet 018817 018593 05/20/2025
Back to Top