Novartis Tumbles 13% Pre-Market as Phase III Trial of DM1 Drug Misses Primary Endpoint

TradingKey - In Tuesday pre-market trading, Novartis (NVS) fell about 13% as its experimental drug del-desiran for treating myotonic dystrophy type 1 (DM1) failed to meet the primary endpoint in a Phase III clinical trial, marking Novartis's third clinical R&D setback within a week.

Source: TradingView

Results from Novartis's HARBOR study showed that del-desiran failed to significantly improve patients' video hand opening time (vHOT) compared with placebo. This metric is primarily used to evaluate the speed at which patients reopen their palms after forming a fist, reflecting the degree of hand myotonia in DM1 patients.

Despite missing the primary endpoint, the company stated that signals of clinical activity were still observed in some secondary endpoints and exploratory analyses, and the drug's safety profile was largely consistent with previously disclosed data. Novartis will continue to analyze the full trial results and communicate with regulatory agencies to determine the next development direction for the del-desiran program.

Del-desiran is one of three antibody-oligonucleotide conjugate drugs Novartis acquired through its roughly $12 billion purchase of Avidity Biosciences, and was a high-profile late-stage pipeline asset in the deal. As the drug had previously received Orphan Drug, Fast Track, and Breakthrough Therapy designations from the U.S. Food and Drug Administration, the Phase III trial failure significantly dampened market expectations for its commercial prospects.

This also marks another R&D setback for Novartis in short succession. Previously, the company's pelacarsen, designed to lower lipoprotein(a)-related cardiovascular risk, failed to reduce major cardiovascular events in a Phase III trial, while certain CAR-T studies for autoimmune diseases were also paused due to safety issues.

The series of adverse outcomes has led investors to reassess the success rate of Novartis's late-stage pipeline, as well as whether acquisitions can offset growth pressures from patent expirations on core drugs such as Entresto.