Bingfang Yan, professor of biomedical and pharmaceutical sciences in the College of Pharmacy, has made his reputation identifying adverse reactions among prescription medications. His studies often examine drugs that hit the marketplace as much-needed therapeutic breakthroughs and their interactions with medications typically prescribed along with them.

His most recent study, reported in the December 2016 issue of the Journal of Hepatology, revealed that the highly effective Hepatitis C drug sofosbuvir (brand names Sovaldi, Harvoni, and EPCLUSA) can adversely interact with the HIV drug tenofovir disoproxil (brand name Viread). The interaction can suppress an enzyme in the liver and kidneys, which then renders the medication ineffective and causes toxicity in those organs.

This is not the first time Yan’s studies have revealed critical drug interactions in standard treatments for conditions affecting millions of people. In 2012 he discovered that the weight-loss drug orlistat, marketed as Xenical and Alli, irreversibly inhibits a key enzyme that might lead to severe toxicity in the liver and kidneys. In 2006 Yan found that the anti-viral drug Tamiflu, which can lessen severity of the flu, would be ineffective in patients also taking the anti-clotting drug Plavix. His findings resulted in new dosing regimens for patients who need both drugs.

As an expert in drug interactions, Yan is one of the authors of the six-volume “Encyclopedia of Drug Metabolism and Interactions.” This reference book is the result of a global effort, featuring prominent authors from 11 different countries.