Abstract
This monograph evaluates the scientific and regulatory underpinnings for bioequivalence (BE) waiver of immediate-release (IR) solid oral meloxicam formulations, as a surrogate for in vivo pharmacokinetic trials. In compliance with ICH (The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use), FDA (Food and Drug Administration), and PMDA (Pharmaceuticals and Medical Devices Agency) bioequivalence guidelines, a systematic characterization was performed on meloxicam's critical attributes, encompassing solubility, permeability, dissolution behavior, pharmacokinetic profiles, therapeutic index, and drug-excipient compatibility. Classified as BCS Class II (low solubility, high permeability), meloxicam nonetheless exhibits a broad therapeutic window and pharmacokinetic characteristics aligning with BE Category I, thus enabling generic product approval via BE waiver with negligible risks of systemic exposure inequivalence. It is noteworthy that current in vitro methodologies are not consistently capable of capturing C(max) disparities of BCS Class II weak acids. BE waiver eligibility for meloxicam IR formulations necessitates three prerequisites: (a) excipient composition identical to the reference listed drug and validated by regulatory authorities; (b) ≥85% dissolution within 30 min at pH 1.2, 4.5, and 6.8; (c) comparable dissolution profiles across these pH conditions. Non-adherence mandates a mandatory in vivo BE assessment.