(Bloomberg) -- Immunomedics Inc. shares more than doubled after a study of its breast cancer drug was stopped early on promising results.

The biotech company surged as much as 115% to $20.20 on Monday after analysts said the results boded well for the drug’s potential approval to treat patients with triple negative breast cancer, an aggressive form of the disease. The news came just days after a Goldman Sachs analyst downgraded the shares on quality-control issues at a manufacturing site.

Immunomedics’s drug, sacituzumab govitecan, has endured a rocky development path. The drug failed to secure accelerated approval from U.S. regulators in January 2019. The stock had fallen 56% this year through Friday’s close ahead of an expected new regulatory decision date on June 2.

Wells Fargo analyst Jim Birchenough upgraded the stock to overweight from equal-weight on Monday, saying he anticipates the drug will ultimately become a standard of care for relapsed/refractory triple negative breast cancer. He cautioned, however, that quality-control issues remain a risk to securing Food and Drug Administration approval.

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