Shares of Novo Nordisk jumped more than 3% on Wednesday after the U.S. Food and Drug Administration issued warning letters to 30 telehealth companies that promoted compounded versions of GLP‑1 drugs, including the firm’s semaglutide and Eli Lilly’s tirzepatide. The move sent a clear signal that the regulator is tightening oversight of direct‑to‑consumer pharmaceutical advertising.

The FDA said the firms violated rules by advertising compounded products as “generic Zepbound” or “generic Mounjaro,” brand names for Lilly’s tirzepatide, and by branding drugs under their