Effect of the Similarity of Formulations and Excipients of Approved Generic Drug Products on In Vivo Bioequivalence for Putative Biopharmaceutics Classification System Class III Drugs

Ping Ren; Theresa Chan; Wen-Cheng Yang; Mitchell Frost; Yan Wang; Markham Luke; Myong-Jin Kim; Robert Lionberger; Yi Zhang

doi:10.3390/pharmaceutics15092366

Effect of the Similarity of Formulations and Excipients of Approved Generic Drug Products on In Vivo Bioequivalence for Putative Biopharmaceutics Classification System Class III Drugs

Pharmaceutics. 2023 Sep 21;15(9):2366. doi: 10.3390/pharmaceutics15092366.

Authors

Ping Ren¹, Theresa Chan¹, Wen-Cheng Yang¹, Mitchell Frost¹, Yan Wang¹, Markham Luke¹, Myong-Jin Kim¹, Robert Lionberger¹, Yi Zhang¹

Affiliation

¹ Division of Therapeutic Performance I, Division of Therapeutic Performance II, Immediate Office, Office of Research and Standards, Office of Generic Drugs, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, 10903 New Hampshire Ave., Silver Spring, MD 20993, USA.

Abstract

One of the potential essential factors that restricts generic industry from applying the Biopharmaceutics Classification System (BCS) Class III biowaiver is adherence to the stringent formulation criteria for formulation qualitative (Q1) sameness and quantitative (Q2) similarity. The present study has investigated formulations and excipients from 16 putative BCS Class III drug substances in a total of 19 drug products via 133 approved abbreviated new drug applications (ANDAs) containing in vivo bioequivalence (BE) studies in human subjects during the time period from 2006 to 2022. We included the BCS Class III drugs in this study by referring to published literature, the World Health Organization (WHO) BCS Class I-IV list, FDA internal assessments, and physicochemical properties (high solubility and low permeability) of specific drug substances. Based upon all 133 approved generic formulations in this study, the highest amount of each different compendial excipient with a total of 40 is defined as its corresponding typical amount that has not shown any potential impact on in vivo drug absorption. In the present study, although only 30.08% of the investigated generic formulations met Q1 the same/Q2 similar formulation criteria for the BCS Class III biowaiver, and while approximately 69.92% failed to meet those criteria with non-Q1/Q2 similar formulations, all test/reference ratios (T/R) and 90% confidence intervals for all instrumental PK parameters (AUC_0-t, AUC_0-inf, and Cmax) met the bioequivalence (BE) criteria (80-125%). The results of formulation assessment suggest that the commonly used excipients without atypical amounts did not impact absorption of 16 putative BCS Class III drug substances. The rate and extent of absorption of drugs appears to be more dependent upon the biopharmaceutic and physiochemical properties of BCS Class III drug substance and less, or not dependent upon their formulations, excipients, and the excipients class. Our findings may lead to a more flexible formulation design space regarding the stringent BCS Class III formulation criteria.

Keywords: Biopharmaceutics Classification System Class III; bioequivalence (BE); biowaiver; excipients; formulation; pharmacokinetic (PK); qualitatively (Q1)/quantitatively (Q2).

Grants and funding

This research received no external funding.