Novartis shares sink after del-desiran drug fails late-stage trial

Novartis shares tanked on Tuesday after the pharmaceutical giant said its del-desiran drug for muscle-wasting disorder failed in a late-stage trial.

The company's stock was last seen down 9.4%, as investors reacted to what was its third drug trial setback in a week. It put the shares on track for their worst trading day ever.

The del-desiran result comes just days after Novartis said its pelacarsen drug failed to reduce the risk of cardiovascular events in a late-stage trial, and a week after announcing it had paused eight clinical trials of an experimental cell therapy, rap-cel, after three patients died. CNBC reached out to Novartis for comment.

Novartis said its global phase III HARBOR study, which had been testing del-desiran in patients with myotonic dystrophy type 1, "did not demonstrate statistically significant improvement versus placebo" on measurements of hand opening time.

Novartis said its global phase III HARBOR study, which had been testing del-desiran in patients with myotonic dystrophy type 1, failed to show that the drug significantly improved patients' ability to open their hands faster than a placebo.

"Novartis is evaluating the full HARBOR dataset and will engage with health authorities to determine the most appropriate development path for del-desiran," the company said in a news release.

Del-desiran is one of three antibody oligonucleotide conjugate therapies that were added to Novartis's neuromuscular pipeline when it acquired Avidity Biosciences for around $12 billion last year.

"Developing therapies for a complex disease like [myotonic dystrophy type 1] remains challenging, and setbacks are part of scientific progress," Shreeram Aradhye, president of development and chief medical officer at Novartis, said in a statement Tuesday.

"As we continue to evaluate the full HARBOR dataset, we remain committed to identifying the most appropriate development path for the del-desiran program and advancing innovative approaches for people living with [myotonic dystrophy] and other serious neuromuscular diseases."