Defense Date


Document Type


Degree Name

Doctor of Philosophy


Pharmaceutical Sciences

First Advisor

Phillip M. Gerk


This dissertation aimed at developing an inhibitor strategy to improve the oral bioavailability (Foral) and systemic exposure (AUC) of buprenorphine (BUP) as well as reduce the variability associated with them. Twenty-seven generally recognized as safe (GRAS) compounds or dietary substances were evaluated for their potential to inhibit the oxidative and conjugative metabolism of BUP, using pooled human intestinal and liver microsomes. In both the organs, oxidation appeared to be the major metabolic pathway with a 6 fold (intestine) and 4 fold (liver) higher intrinsic clearance than glucuronidation. Buprenorphine was predicted to show low and variable Foral, AUC, and a large total clearance. The biorelevant solubilities of 5 preferred inhibitors were incorporated in the final model. An inhibitor dosing strategy was identified to increase Foral and reduce the variability in oral BUP AUC. These results demonstrate the feasibility of the approach of using GRAS or dietary compounds to inhibit the presystemic metabolism of buprenorphine and thus improve its oral bioavailability. This inhibitor strategy has promising applicability to a variety of drugs suffering from low and variable oral bioavailability due to extensive presystemic oxidative and conjugative metabolism.


© Neha Maharao

Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission


Available for download on Saturday, May 07, 2022