Washington Editor

CV Therapeutics Inc. initiated a pivotal Phase III trial for CVT-3146, a candidate for use as a pharmacologic stress agent in cardiac perfusion imaging studies.

CVT-3146 is meant to help patients who are undergoing a cardiac perfusion imaging test who can't exercise sufficiently to generate the increase in coronary blood flow needed for the test. CVT-3146 is being studied to determine if it could temporarily increase the coronary blood flow to mimic what would be produced from exercise.

While the Phase III begins, CV Therapeutics is ticking down the hours to its FDA action date on Ranexa (ranolazine), a proposed treatment for chronic angina. John Bluth, CV Therapeutics' director of corporate communications in Palo Alto, Calif., told BioWorld Today the company's PDUFA date for Ranexa is today. (PDUFA, or the Prescription Drug User Fee Act, compels the FDA to take action within a given time on drug or biologics applications.)

In August, the FDA and CV Therapeutics mutually agreed to cancel a September panel meeting for the Ranexa application. The company's stock fell $7.31, or 20.8 percent that day, closing at $27.87. (See BioWorld Today, Aug. 5, 2003.)

But last week, CV Therapeutics' stock rose when the company said its Ranexa hearing before the Cardiovascular and Renal Drugs Advisory Committee was set for Dec. 9. The company's stock (NASDAQ:CVTX) moved up $4.23, or 23.2 percent, on that news. (See BioWorld Today, Oct. 27, 2003.)

CV Therapeutics' stock (NASDAQ:CVTX) was up 31 cents Wednesday, closing at $23.46 on news of the Phase III trial.

While Ranexa waits for what's next, CVT-3146 is moving right along.

CVT-3146, a selective A2A-adenosine receptor agonist, is being developed via a deal with Fujisawa Healthcare Inc., a subsidiary of Fujisawa Pharmaceutical Co. Ltd., of Osaka, Japan.

Fujisawa markets a stress agent called Adenoscan. The active ingredient in Adenoscan, adenosine, interacts with a variety of adenosine receptors, including A2A, which stimulates vasodilation and coronary blood flow so that cardiac perfusion imaging studies can be done without exercise. But because adenosine acts on all of its receptors, not just A2A, it can cause side effects.

On partnering with CV Therapeutics, Fujisawa agreed to pay $34 million up front and in potential milestones for exclusive North American rights to CVT-3146. Fujisawa will fund 75 percent of development costs and is compelled to pay CV Therapeutics a double-digit royalty. CV Therapeutics retains all rights outside the Fujisawa territory. (See BioWorld Today, July 13, 2000.)

CV Therapeutics received a $3 million milestone payment on initiating the Phase III trial. Since signing the collaboration, CV Therapeutics has received $15 million (including the recent milestone) in payments, plus reimbursements for clinical development.

The company did not provide additional information on the design of the Phase III trial and Bluth said it is too early to discuss a possible timeline related to enrollment or possible completion.

In a prepared statement, Louis Lange, chairman and CEO of CV Therapeutics, said, "We are excited to move our third product into Phase III testing and we believe that the rapid bolus dosing and the selective binding of CVT-3146 to the A2A-adenosine receptor could potentially offer significant improvements for the rapidly growing population of patients needing stress-imaging evaluations. (The third product is Tecadenoson, for reduction of rapid heart rate during atrial arrhythmias.)

In an open-label Phase II trial, CVT-3146 produced a dose-dependent increase in coronary blood flow velocity in patients undergoing cardiac catheterization. CVT-3146 was generally well tolerated, and drug-related adverse events, including chest discomfort, increased heart rate, hypotension, flushing and shortness of breath, were mild and self-limited, the company said.