On November 17, 2025, the FDA published the final guidance for industry, “Considerations for Waiver Requests for pH Adjusters in Generic Drug Products Intended for Parenteral, Ophthalmic, or Otic Use,” which helps applicants prepare an abbreviated new drug application (ANDA) that references a reference listed drug (RLD) intended for parenteral, ophthalmic, or otic use but seeks approval of a drug that is qualitatively (Q1) different or quantitatively (Q2) different from the RLD with respect to a pH adjuster(s).