Allergic reactions force Regado to pull the plug on PhIII anticoagulant study

Regado Biosciences just got called for its third strike by the safety board. The biotech, which raised tens of millions of dollars to fund a go-it-alone clinical program for an experimental anticoagulant, says the board called on Regado ($RGDO) to shutter its Phase III study after determining that the serious allergic reactions investigators had recorded in the study made it impossible to go on.

The company's stock plunged more than 50% in early trading. That's still a restrained initial response, considering that Regado's only other clinical stage program, a subcutaneous injection of the same two drugs used in Revolixys, is in Phase I.

"The DSMB indicated that the level of serious allergic adverse events associated with Revolixys was of a frequency and severity such that they recommended that we do not enroll any further patients in the REGULATE-PCI trial," said Regado CEO David Mazzo in a statement. "We will now undertake a complete review of the unblinded database from REGULATE-PCI, which we expect will take several months to complete."

Regado CEO David Mazzo

Basking Ridge, NJ-based Regado bet the farm on Revolixys (REG1), which uses two agents--pegnivacogin and anivamersen--to control bleeding during a coronary intervention and open heart surgery. The biotech hoped the $150 million Phase III study would prove that the combo could give physicians a tool to manage coagulation, 'dialing' the anticoagulation effect up or down to enable doctors to safely hit a maximum dose for each patient. Pegnivacogin is a Factor IXa inhibitor which can be reversed partially or completely by anivamersen. 

But investors always proved hard to convince. The biotech's IPO limped out of the gate in 2013, raising $47 million with a heavily marked down share price, leaving the company far short of the cash it needed to complete Phase III. Studies like this are rarely done by lone biotechs. A study of this size almost always requires a major partner to pull it off, though the IPO market has offered an alternative financing mechanism over the past 18 months.

Back in late 2012 Baxter's venture arm allied with Rusnano to lead a $51 million round for the company, with cash from Edmond de Rothschild Investment Partners, Domain Associates, Quaker Partners, Aurora Funds and Caxton Advantage Life Sciences Fund.

- here's the release