Novartis faces heightened investor scrutiny of its acquisition strategy after del-desiran, the centerpiece of its $12 billion Avidity Biosciences purchase, failed a late-stage study in myotonic dystrophy type 1. The result marked the company’s second major clinical setback in days, following pelacarsen’s failure to meet the primary endpoint in the Lp(a)HORIZON cardiovascular trial. Artisan Partners has called for stronger board oversight of mergers and acquisitions while supporting CEO Vas Narasimhan, who has led Novartis since 2018. Novartis shares fell sharply, with one report putting the one-day decline at 11% and another reporting a 14% fall in U.S.-listed shares, erasing nearly $30 billion in market value. Investors are focused on whether future deals can replenish the pipeline ahead of patent expirations, although Novartis has no plans to change its M&A or business-development approach. Detailed data from remibrutinib studies in relapsing multiple sclerosis are due at an October medical meeting.