Kessler Topaz Meltzer & Check, LLP (KTMC) is investigating potential violations of federal securities laws by Madrigal Pharmaceuticals, Inc. on behalf of investors who purchased or acquired its securities and suffered significant financial losses. Madrigal disclosed in its quarterly report on November 3, 2026, that its former Senior Vice President and Head of Clinical Development had filed a whistleblower complaint on October 9, 2026. The complaint alleges that the former executive reported adverse safety findings and unreproducible efficacy data involving Rezdiffra, Madrigal's only approved drug, to the company's Senior Executive Leadership. It further alleges that Madrigal suppressed adverse liver-injury data, presented efficacy results that could not be reconciled with its source data, and allowed an unblinded Board member to control the adjudication of clinical outcomes. Madrigal's stock fell over 8% after the disclosure. KTMC said investors who suffered losses may have legal rights under federal securities laws and invited them to contact the firm at no cost or obligation. KTMC is a U.S. plaintiff-side law firm focused on securities-fraud class actions and global investor protection, with offices in Pennsylvania and California; it says it has recovered more than $25 billion for clients and represented classes.