Shares of ARYx Therapeutics tanked $1.81 (42.99%) to $2.40 after word that its novel anticoagulant drug tecarfarin (ATI-5923) failed a Phase 2/3 study.

The study was designed to evaluate patients’ therapeutic range (TTR) vs. warfarin using INR (International Normalized Ratio), which is the standard method of evaluating anticoagulation.

The drug was supposed to be superior to warfarin, but ended up demonstrating similar efficacy. Patients on tecarfarin stayed within TTR 74.0% of the time vs. patients on warfarin who stayed within TTR 73.2% of the time (p=0.506).

ARYx CEO Paul Goddard said this:

“While we are obviously disappointed at the outcome of this trial, tecarfarin achieved the results we anticipated based upon two earlier Phase 2 studies. We continue to demonstrate a time within therapeutic range of INR that remains consistent from trial to trial, whether dosing decisions are made by treating physicians or through a centralized dosing control. In contrast, warfarin patients did much better than we had reason to expect and as a result we did not achieve statistical significance. This appears to be due in no small part to the central dose control center that we established for the trial, and to the ability of the center to anticipate the potential daily pitfalls of warfarin use. Such oversight for warfarin control dosing was necessary for our double-blind trial even though it’s not seen in normal clinical practice. An initial analysis of the data reinforces the importance of comparing normal tecarfarin administration to typical warfarin practice in a so-called real world setting. There are still a lot of data to be analyzed from this trial. Once we have fully analyzed both the efficacy and safety results, we will continue our on-going partnership discussions with several large pharmaceutical companies to determine the best path forward in the future development of tecarfarin. Of course, as we have previously stated, we also remain focused on the licensing of budiodarone and ATI-7505.”

Warfarin, a blood-thinner, has been around for 60 years and was initially marketed as a pesticide against rats and mice.

Here’s ARYx’s press release.

Anonymous Tip? Comments? Contact us: hr AT iguanabio DOT com

Related Posts