Complex generic products are typically harder to develop, which means that many complex products face less competition than other products, and therefore can be more expensive and less accessible to the patients who need them. The initiatives below are aimed at ensuring FDA’s regulatory requirements for complex generic drugs are streamlined, predictable, and science-based, to help reduce the time, uncertainty, and cost of drug development.

• Revised Draft Guidance for Industry: Assessing Adhesion with Transdermal and Topical Delivery Systems for ANDAs (April 2023)
• Revised Draft Guidance for Industry: Assessing the Irritation and Sensitization Potential of Transdermal and Topical Delivery Systems for ANDAs (April 2023)
• Revised Draft Guidance for Industry: Product-Specific Guidance (PSG) Meetings Between FDA and ANDA Applicants Under GDUFA (February 2023)
• Draft Guidance for Industry: Sameness Evaluations in an ANDA – Active Ingredients (November 2022)
• Draft Guidance for Industry: Physicochemical and Structural (Q3) Characterization of Topical Drug Products Submitted in ANDAs (October 2022)
• Draft Guidance for Industry: IVRT Studies for Topical Drug Products Submitted in ANDAs (October 2022)
• Draft Guidance for Industry: IVPT Studies for Topical Drug Products Submitted in ANDAs (October 2022)
• Draft Guidance for Industry: Topical Dermatologic Corticosteroids: In Vivo Bioequivalence (October 2022)
• Guidance for Industry: Formal Meetings between FDA and ANDA Applicants of Complex Products under GDUFA (November 2020)
• Manual of Policies and Procedures (MAPP): Evaluating Requests for and Conducting Product Development and Pre-Submission Pre-ANDA Meetings (October 2022)
• Draft Guidance for Industry: How To Obtain a Covered Product Authorization (September 2022)
• Manual of Policies and Procedures (MAPP): Classifying Approved New Drug Products and Drug-Device Combination Products as Complex Products for Generic Drug Development Purposes (April 2022)
• Draft Guidance for Industry: Considerations for Waiver Requests for pH Adjusters in Generic Drug Products Intended for Parenteral, Ophthalmic, or Otic Use (April 2022)
• Guidance for Industry: Bioequivalence Studies with Pharmacokinetic Endpoints for Drugs Submitted Under an ANDA (August 2021)
• Guidance for Industry: ANDAs for Certain Highly Purified Synthetic Peptide Drug Products That Refer to Listed Drugs of rDNA Origin (May 2021)
• Draft guidance for industry, Orange Book Questions and Answers, which is intended to assist prospective and current drug product applicants and approved application holders in effectively using the Orange Book. (May 2020)
• A public docket to solicit comments on how stakeholders and the public use the Orange Book and whether and how it can be improved. (May 2020)
• A public docket to solicit comments on the listing of patent information in the Orange Book. (May 2020)
• Public Workshop: Complex Generic Drug Product Development (September 2019)
• Launched website with information on Upcoming Product-Specific Guidances for Complex Generic Drug Product Development (April 2019)
• Revised Draft Guidance for Industry “Assessing Adhesion With Transdermal and Topical Delivery Systems for Abbreviated New Drug Applications” (October 2018)
• Draft Guidance for Industry “Assessing the Irritation and Sensitization Potential of Transdermal and Topical Delivery Systems for Abbreviated New Drug Applications” (October 2018)
• FDA/DIA Regulatory Science Public Workshop: Complex Generic Drug-Device Combination Products (October 2018)
• Regulatory Science Public Workshop: Complex Generic Drug Product Development (September 2018)
• Regulatory Science Public Meeting: FY 2018 Generic Drug Regulatory Science Initiatives (May 2018)
• Regulatory Science Public Workshop: New Insights for Product Development and Bioequivalence Assessments of Generic Orally Inhaled and Nasal Drug Products (January 2018)
• Final Guidance for Industry: General Principles for Evaluating the Abuse Deterrence of Generic Solid Oral Opioid Drug Products (November 2017)
• Regulatory Science Public Workshop: Topical Dermatological Generic Drug Products (October 2017) 
• Draft Guidance for Industry: Determining Whether to Submit an ANDA or a 505(b)(2) Application (October 2017)
• Regulatory Science Public Workshop: Demonstrating Equivalence of Generic Complex Drug Substances and Formulations (October 2017)
• Regulatory Science Public Workshop: Leveraging Quantitative Methods and Modeling to Modernize Generic Drug Development (October 2017)
• Draft Guidance for Industry: ANDAs for Certain Highly Purified Synthetic Peptide Drug Products that Refer to Listed Drugs of rDNA Origin (October 2017)