* Brilinta onset greater at 0.5, 1, 2, 4, 8 and 24 hours
* At 2 hrs over 50 pct effect seen in 98 pct on Brilinta
* Brilinta effect 2 days less to wear off than Plavix
By Bill Berkrot and Ransdell Pierson
ORLANDO, Fla.,, Nov 18 (Reuters) - AstraZeneca’s (AZN.L) experimental Brilinta blood clot preventer begins working much faster than widely-used Plavix and the intended effect wears off more quickly, according to data from a mid-stage study presented on Wednesday.
Each of those effects is extremely desirable depending on the type of procedure a heart patient is in need of, and could give AstraZeneca an important marketing edge when its drug begins competing with Plavix, now the standard of care with annual sales of about $9 billion for Bristol-Myers Squibb Co(BMY.N) and Sanofi-Aventis (SASY.PA).
Analysts see Brilinta as a potential multibillion-dollar a year seller for AstraZeneca, which plans to file an application seeking U.S. approval later this year.
Brilinta showed greater inhibition of platelet aggregation, or clumping, than Plavix at half an hour, one hour, two, four eight and 24 hours after patients received the initial treatment dose, according to data presented at the American Heart Association scientific meeting in Orlando.
In a large Phase III trial released earlier this year, Brilinta demonstrated superiority to Plavix in preventing heart attacks and death with no increased risk of major bleeding, alleviating concerns that safety might be compromised by higher efficacy. Bleeding is the major source of worry with drugs that work by keeping blood cells called platelets from clumping together.
The Phase II onset/offset data unveiled Wednesday was designed to give better understanding of how Brilinta, known chemically as ticagrelor, works in the body.
At two hours after initial dosing, 98 percent of Brilinta patients achieved greater than 50 percent platelet clumping inhibition compared with 31 percent of those on Plavix — a result deemed to be highly statistically significant.
And 90 percent of those on Brilinta reached greater than 70 percent anti-clotting action versus just 16 percent in the Plavix group at two hours.
Speed of action is beneficial as these type of drugs are used routinely in those in need of emergency artery-clearing angioplasty, where the current goal is to get the procedure started within 90 minutes of a patient turning up at the emergency room.
On the flip side, heart patients in need of more invasive coronary artery bypass procedures must wait until the anti-clotting effect of these drugs wears off in order to reduce the risk of catastrophic bleeding during surgery.
It typically takes about five days after the last dose of Plavix for clotting activity to return to normal enough levels to safely perform bypass surgery. Brilinta patients reached a comparable level three days after stopping the medicine, the study found. (Reporting by Bill Berkrot and Ransdell Pierson, editing by Dave Zimmerman)