Back to Explorer

Considerations for Waiver Requests for pH Adjusters in Generic Drug Products Intended for Parenteral, Ophthalmic, or Otic Use: Guidance for Industry

FinalCenter for Drug Evaluation and Research11/17/2025

Description

The Food and Drug Administration (FDA or Agency) is announcing the availability of a final guidance for industry entitled “Considerations for Waiver Requests for pH Adjusters in Generic Drug Products Intended for Parenteral, Ophthalmic, or Otic Use.” This guidance is intended to assist abbreviated new drug application (ANDA) applicants that reference a drug product intended for parenteral, ophthalmic, or otic use in seeking approval of a drug that is qualitatively (Q1) different or quantitatively (Q2) different from the reference listed drug (RLD) with respect to the pH adjuster(s). This guidance describes how FDA intends to evaluate a request for a waiver of Agency requirements for a Q1 or Q2 difference in pH adjuster, including recommendations on the type of information to provide in support of such a waiver request. This guidance finalizes the draft guidance of the same title issued on April 14, 2022.

Scope & Applicability

Product Classes

6
Generic Drug Product

Drug products referencing a reference listed drug; Proposed products seeking approval via ANDA.

Reference Listed Drug

The drug product identified by the applicant for comparison; Comparison of ANDA product to RLD for pH adjuster differences

Parenteral Drug Product

Injectable products subject to specific inactive ingredient rules.

Ophthalmic Drug Product

Eye products subject to specific inactive ingredient rules.

Otic Drug Product

Ear products subject to specific inactive ingredient rules.

RLD

Reference Listed Drug used as the basis for an ANDA submission.

Stakeholders

1
Applicant

Entity submitting development data and knowledge; Entity performing the work process for change

Regulatory Context

Attributes

8
Qualitatively (Q1) different

Difference in the type of inactive ingredients

Q1 or Q2 difference

Qualitative or quantitative difference in inactive ingredients

Quantitatively (Q2) different

Difference in the concentration of inactive ingredients

Q1 Difference

Qualitative difference in inactive ingredients.

Q2 Difference

Quantitative difference in inactive ingredients.

Quantum Satis

Amount as much as necessary (q.s.) to achieve a target.

Osmolality

Physicochemical characteristic used to assure product acceptability.

Viscosity

Physicochemical characteristic used to assure product acceptability.

Identified Hazards

Hazards

1
New counter-ion species

Potential safety concern arising from different pH adjusters.

Related CFR Sections (7)

Related Warning Letters (5)

  • Unapproved New Drugs/Misbranded

    Mihon Corp. d/b/a VitalityVita and Boulla, LLC

    2025-01-28
  • Finished Pharmaceuticals/Unapproved New Drug/Misbranded

    East Fork Cultivars

    2023-12-26
  • Finished Pharmaceuticals/Unapproved New Drug/Misbranded

    ElectRx and Health Solutions, LLC

    2023-03-14
  • Finished Pharmaceuticals/Unapproved New Drug/Misbranded

    HIS Enterprise Inc dba Adam’s Secret USA, LLC

    2023-01-17
  • Unapproved New Drugs/Misbranded

    Wave Miami LLC

    2020-01-28

See Also (8)