MacroGenics shares plunged 77.4% on Friday, erasing $773.2 million in market value, after the biotech reported late Thursday that five patients died in a study of the company’s cancer drug. MacroGenics said two of the deaths were deemed unrelated to the drug, known as vobra duo, according to researchers. “The cause and effect with regard to the drug is still being investigated,” Chief Executive Scott Koenig said of the three deaths on the company's first quarter earnings call on Thursday.
The Wall Street Journal