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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initial step for selecting methodology for generic drug product development, applicants are referred to the following draft guidance: Draft Guidance for Industry on Bioequivalence Studies With Pharmacokinetic Endpoints for Drugs Submitted Under an Abbreviated New Drug Application (ANDA) (August 2021).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 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 (PSGs) describing the Agency's current thinking and expectations on how to develop generic drug products therapeutically equivalent to specific RLD.

FDA publishes these PSGs 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 20221 (GDUFA III). 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 2 years after the date of approval, and for 75 percent of such NDA products within 3 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 2 years after the date of approval for 90 percent of such products.
In addition to its GDUFA III commitments, FDA will prioritize publishing of PSGs based on public health priorities, drug availability and accessibility, public requests for guidance, stakeholder interest in ANDA submission.

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: 2069

Product-Specific Guidances for Specific Products Arranged by Active Ingredient


Search by Active Ingredient or by RLD or RS Number


Newly Added Guidances since November 17, 2022

Active Ingredient (link to Specific Guidance) URL Type Route Dosage Form RLD or RS Number Date Recommended
Ammonium Lactate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_020508.pdf Draft Topical Cream 020508 11/17/2022
Ammonium Lactate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_019155.pdf Draft Topical Lotion 019155 11/17/2022
Budesonide https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_215935.pdf Draft Oral Capsule, Delayed Release 215935 11/17/2022
Calcitonin Salmon https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_017769.pdf Draft Injection Injectable 017808 11/17/2022
Clindamycin Phosphate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_215650.pdf Draft Vaginal Gel 215650 11/17/2022
Deferiprone https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_212269.pdf Draft Oral Tablet 212269 11/17/2022
Drospirenone; Estetrol https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_214154.pdf Draft Oral Tablet 214154 11/17/2022
Eteplirsen https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_206488.pdf Draft Intravenous Solution 206488 11/17/2022
Fidaxomicin https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_213138.pdf Draft Oral For Suspension 213138 11/17/2022
Fosdenopterin Hydrobromide https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_214018.pdf Draft Intravenous Powder 214018 11/17/2022
Hydrocortisone https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_016199.pdf Draft Rectal Enema 016199 11/17/2022
Hydroxyurea https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_208843.pdf Draft Oral Tablet 208843 11/17/2022
Inotersen Sodium https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_211172.pdf Draft Subcutaneous Solution 211172 11/17/2022
Ketotifen Fumarate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_021066.pdf Draft Ophthalmic Solution/Drops 021066 021996 11/17/2022
Magnesium Sulfate; Potassium Chloride; Sodium Sulfate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_213135.pdf Draft Oral Tablet 213135 11/17/2022
Melphalan Flufenamide Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_214383.pdf Draft Intravenous Powder 214383 11/17/2022
Miconazole Nitrate; White Petrolatum; Zinc Oxide https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_021026.pdf Draft Topical Ointment 021026 11/17/2022
Mometasone Furoate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_215712.pdf Draft Nasal Spray, Metered 215712 11/17/2022
Nicardipine Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_019488.pdf Draft Oral Capsule 019488 11/17/2022
Omeprazole Magnesium https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_078878.pdf Draft Oral Capsule, Delayed Release 078878 11/17/2022
Patisiran Sodium https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_210922.pdf Draft Intravenous Solution 210922 11/17/2022
Ponesimod https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_213498.pdf Draft Oral Tablet 213498 11/17/2022
Ranolazine https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_216018.pdf Draft Oral Granules, Extended Release 216018 11/17/2022
Tepotinib Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_214096.pdf Draft Oral Tablet 214096 11/17/2022
Tivozanib Hydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_212904.pdf Draft Oral Capsule 212904 11/17/2022
Triamcinolone Acetonide https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_208845.pdf Draft Intra-Articular For Suspension, Extended Release 208845 11/17/2022
Trilaciclib Dihydrochloride https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_214200.pdf Draft Intravenous Powder 214200 11/17/2022
Varenicline Tartrate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_213978.pdf Draft Nasal Spray 213978 11/17/2022
Voclosporin https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_213716.pdf Draft Oral Capsule 213716 11/17/2022

Newly Revised Guidances since November 17, 2022

Active Ingredient (link to Specific Guidance) URL Type Route Dosage Form RLD or RS Number Date Recommended
Acyclovir https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_203791.pdf Draft Buccal Tablet 203791 11/17/2022
Baricitinib https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_207924.pdf Draft Oral Tablet 207924 11/17/2022
Calcium Carbonate; Famotidine; Magnesium Hydroxide https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_020958.pdf Draft Oral Tablet, Chewable 020958 11/17/2022
Daunorubicin Citrate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_050704.pdf Draft Injection Injectable, Liposomal 050704 11/17/2022
Deferiprone https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_021825.pdf Draft Oral Tablet 021825 11/17/2022
Ethinyl Estradiol; Norethindrone Acetate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_021065.pdf Draft Oral Tablet 021065 11/17/2022
Ferric Oxyhydroxide https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_020955.pdf Draft Injection Injectable 020955 11/17/2022
Ferric Oxyhydroxide https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_017441.pdf Draft Injection Injectable 017441 11/17/2022
Goserelin Acetate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_020578.pdf Draft Implantation Implant 020578 11/17/2022
Goserelin Acetate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_019726.pdf Draft Implantation Implant 019726 11/17/2022
Icosapent Ethyl https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_202057.pdf Draft Oral Capsule 202057 11/17/2022
Lapatinib Ditosylate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_022059.pdf Draft Oral Tablet 022059 11/17/2022
Lidocaine https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_207962.pdf Draft Topical Patch 207962 11/17/2022
Oxycodone https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_208090.pdf Draft Oral Capsule, Extended Release 208090 11/17/2022
Progesterone https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_020701.pdf Draft Vaginal Gel 020701 11/17/2022
Ranolazine https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_021526.pdf Draft Oral Tablet, Extended Release 021526 11/17/2022
Rifaximin https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_021361.pdf Draft Oral Tablet 021361 11/17/2022
Sodium Phosphate, Dibasic, Anhydrous; Sodium Phosphate, Monobasic, Monohydrate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_021892.pdf Draft Oral Tablet 021892 11/17/2022
Sumatriptan Succinate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_020080-Vial.pdf Draft Subcutaneous Injectable, Vial 020080 11/17/2022
Sumatriptan Succinate https://www.accessdata.fda.gov/drugsatfda_docs/psg/PSG_020080-Autoinj.pdf Draft Subcutaneous Injectable, Autoinjector 020080 11/17/2022
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