A large clinical trial, involving over 18,000 patients in 43 countries with acute coronary syndrome, showed that Brilinta (ticagrelor) worked better than Sanofi-Aventis's (SNY) and Bristol-Myers Squibb's (BMY) popular drug Plavix (clopidogrel) in preventing heart attacks, strokes and deaths from cardiovascular causes.
Brilinta, Plavix, and a third competitor -- Effient (prasugrel), from Eli Lilly (LLY) and Daiichi Sankyo -- are antiplatelet treatments, meaning they stop the blood platelets from clumping together and forming life-threatening clots in arteries.
"Brilinta is a superior drug," says Dr. Paul Gurbel, director of the Center for Thrombosis Research at Sinai Hospital in Baltimore. "It has faster onset. It reaches maximum antiplatelet effect within two hours compared to eight hours for clopidogrel. And its effect wears off faster," which can benefit patients awaiting invasive surgical procedures that entail risks of bleeding. Gurbel led several pivotal studies related to Brilinta.
An Odd Anomaly in U.S. Test Subjects
Because of the way they operate, blood thinners can cause bleeding. Brilinta patients were equally likely to suffer from serious bleeding as Plavix patients, Gurbel explains, meaning the drug didn't compromise safety.
Moreover, Brilinta works just as well in patients with genetic variations and therefore doesn't require genetic testing, unlike Plavix. But it's not just that, explains Gurbel. Patients can prove resistant to Plavix regardless of their genetics, which could require doctors to switch them to another drug. "Brilinta, which goes straight to the platelet and has more pharmacodynamic effects wouldn't need switching," Gurbel says.
However, there are concerns too, mainly what's been dubbed the North American paradox: a thus-far unexplained higher rate of negative outcomes in U.S. patients who took Brilinta rather than Plavix. "This could be the result of chance and not indicative of any failure of the drug," Gurbel says, and also suggests it could be because of higher aspirin intake among U.S. patients. "Bottom line is we don't have a good explanation for this."
Potential Sales of $2 Billion
Naturally, this is a concern for the FDA. While an FDA advisory panel voted 7-1 to recommend approval of Brilinta in July, the FDA delayed its decision from September to December because of the issue. Platelet expert Dr. Victor Serebruany of HeartDrug Research Laboratories and Johns Hopkins University Osler Medical Center in Towson, Md., tried to help the FDA understand the regional differences in the study's results, the Financial Times reported last month. Serebruany in fact questions some of the trial's results.
Plavix was the second-biggest-selling drug in the world last year, with global revenue of nearly $10 billion, and Brilinta could have a shot at a big piece of that pie. Analysts have estimated sales of Brilinta could reach $2 billion or more within three to five years, considerably adding to AZN's earnings forecast.
Last week, the European Commission approved Brilinta -- marketed in Europe as Brilique -- for the prevention of clots in adult patients with acute coronary syndromes. Thursday's announcement will answer the question of whether the FDA will follow suit. Investors seem to largely be betting on a positive outcome -- AstraZeneca share prices have risen since the start of December.