It's not the most prominent biotech, but it has an important claim to fame.Madrigal Pharmaceuticals' (MDGL -0.79%) shares are down by 27% over the past year, while the S&P 500 is up by 26%. However, this poor performance hardly reflects the progress the biotech has made. Madrigal recently earned regulatory approval for Rezdiffra, a therapy for non-alcoholic steatohepatitis (NASH). Not only was Rezdiffra Madrigal's first product on the market, but it is also the first and only approved by the U.S. Food and D ...