
Shares in Macrogenics, a Rockville, Md., developer of cancer drugs, doubled in premarket trading after the company announced positive results for a new breast cancer drug on Wednesday.
“This is probably one of the biggest surprises of the year so far,” Umer Raffat, a biotechnology analyst at Evercore ISI, an investment bank, wrote in a note to investors. He argued that the drug in question, margetuximab, could generate as much as $650 million in worldwide annual sales based on the results, and that the market capitalization of Macrogenics, which was $469 million as of Tuesday’s close, could soar to $2 billion.
The study in question, called SOPHIA, compared margetuximab to Roche’s Herceptin, one of the most important drugs in biotech history, in 536 heavily pretreated women with metastatic breast cancer. Patients in the margetuximab arm had a 24 percent reduction in the risk of progression (defined as tumor growth) or death compared to those on Herceptin. The result was statistically significant, with a p value of 0.033. (By custom, statistical significance means a p value is less than 0.05.)