Cardiome Sinks on FDA Info Request (Update)

Updated from 12:27 p.m. EDT.

Cardiome(CRME Quote), publicly pining for partners and potential acquirers, instead got another regulatory delay on Monday as the Food and Drug administration wants a closer look at safety risks of its irregular heart rhythm drug.

Investors, who've long awaited approval for atrial fibrillation (AF) treatment vernakalant, pushed Cardiome's shares down $2.17, or 18.2%, to $9.78 after the FDA issued an "approvable" letter with data requests.

In order to approve the drug -- which is being co-developed with Japanese drugmaker Astellas and goes by the brand name Kynapid -- the FDA is asking for safety information from all ongoing and completed studies on the treatment, regardless of what they are testing it for, the form of the drug, and what dose it is.

The FDA is concerned with serious adverse events in eight patients with compromised ventricular function. Regulators are asking Cardiome and Astellas for evidence in support of the drug's risk benefit profile in this population. Without such evidence, the FDA could decide to restrict the use in that subset on the drug's label.

Monday's letter could result in the need for an additional clinical study, although Cardiome said it was optimistic about its chances of addressing the issues with already-available data. The companies noted in a press release that they will meet with the FDA within the next few days, but anticipate it will take several months to put together an appropriate response.

Now, the earliest approval date possible is nine months from today, noted BMO Capital Markets' Chrstine Charette. She estimates that if an additional trial is required it will delay approval by at least 18 months.