Novartis (NVS) Suffers its Third Drug Trial Setback in a Week, and its Worst Trading Day in Years

On September 8, 2026, CNBC reported that Novartis AG (NYSE: NVS ) shares fell about 10% after the company said its experimental drug del-desiran failed to meet its primary goal in a late-stage trial for myotonic dystrophy type 1.

It marked the company's third clinical setback in a week following the earlier failure of cardiovascular drug pelacarsen and a separate pause of eight trials of cell therapy rap-cel after three patient deaths. The decline erased roughly 24 billion Swiss francs, or about $29.6 billion, in market value and put Novartis on pace for one of its worst trading days in company history.

Remibrutinib provides a major remaining pipeline catalyst since Novartis AG (NYSE: NVS ) reported successful late-stage results for remibrutinib in multiple sclerosis. It gives investors a credible growth driver after the failures of pelacarsen and del-desiran. The business expects more remibrutinib data later this year, making the drug an important test of whether its remaining pipeline can help long-term growth.

Novartis still expects 5% to 6% annual sales growth through 2030. Management reaffirmed its full-year financial guidance and maintained its target for 5% to 6% compound annual sales growth from 2025 through 2030. That guidance shows the company still expects its overall portfolio and remaining pipeline assets to offset pressure from aging drugs.

The company retains a diversified commercial portfolio. The del-desiran failure removes a potentially important future revenue contributor, but Novartis still makes substantial revenue from its existing medicines. It also retains other pipeline assets. That diversification gives the firm financial capacity to absorb individual clinical failures while it rebuilds investor confidence in its growth pipeline.

Two major pipeline failures now threaten Novartis AG (NYSE: NVS )' growth plans. Novartis has missed two of three key pipeline tests investors were counting on this year after pelacarsen and del-desiran failed late-stage trials. The setbacks increase pressure on remibrutinib and raise concerns about the company's ability to replace revenue as Entresto and other older medicines approach patent expiries.

The del-desiran failure removes a major future revenue opportunity. Barclays had estimated peak annual sales of about $3.1 billion for del-desiran and assigned the drug a 60% probability of success after positive mid-stage results. The failed trial eliminates that potential growth contribution. It also raises questions about the $12 billion Avidity acquisition that brought the drug into Novartis' pipeline.