Some of the endpoints in these trials are kind of soft, and they aren't prospective studies," said Dr. Anthony DeMaria, director of the cardiovascular center at the University of California San Diego who was not involved in the trials. "It's encouraging that the larger trials are likely to succeed, but we still need those trials."
Dr Marc Sabatine, lead investigator of the Repatha study, said data for both drugs "are very consistent ... it appears that cutting LDL by 61 percent translates to a roughly 50 percent reduction in cardiovascular events."
Numerous trials have shown that PCSK9 inhibitors significantly lower blood levels of "bad" LDL cholesterol, but investors expect widespread use will hinge on whether the drugs are proven to prevent death, heart attacks and other serious heart problems.