It may be one of the most common diseases you've never heard of: NASH, or nonalcoholic steatohepatitis, is a liver disease increasing in prevalence along with obesity.
Dean Hum, chief scientific officer of French biotech Genfit, said it may affect as much as 12 percent of the U.S. population.
Genfit is competing with drugmakers including Intercept to bring medicines to market for NASH, which has captured investors' attention and made stocks—particularly Intercept's—especially volatile.
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"NASH is becoming a real issue, a problem on a worldwide scale," Hum said in an interview Monday at the American Association for the Study of Liver Diseases conference in Boston. "One of the better studies looking at prevalence pegs it at about 12 percent in the adult U.S. population, and a significant proportion of those patients have advanced disease which requires treatment."