"Ticagrelor is an investigational drug, and has not been approved by any regulatory authorities," the company said in a statement released Wednesday. "Ticagrelor's efficacy and safety have been studied in a clinical trial setting in the ACS [acute coronary syndrome] population, and in the real-world setting the efficacy and safety is still unknown."
"The effectiveness of Plavix has been proven, and the safety profile supported by four large clinical studies involving 81,000 patients across the entire spectrum of its approved cardiovascular indications," the statement continued. "Plavix has been prescribed to more than 100 million patients worldwide during the 11 years it has been on the market. Plavix is recommended in national and international guidelines for heart attack, stroke and/or PAD [peripheral arterial disease] patients at risk for future atherothrombotic events, and is an important treatment option for millions of patients at cardiovascular risk."
However, one expert was impressed by the latest findings on Brilinta.
"This were top-line results," said Dr. Kirk Garratt, clinical director of interventional cardiovascular research at Lenox Hill Hospital in New York City. "It's important that, for the first time, we have a drug that is not only more powerful in its ability to control platelet behavior but able to do that without increasing bleeding. That's astonishing."
Still, enthusiasm may need to be tempered, he said.
Garratt pointed out that the vast majority of participants in the trial came from Europe, the Middle East and Africa, not North America. "And in that group of North American patients there was no benefit for ticagrelor," he said. "It could just be play of chance but you can't get around the fact that when the population was [studied] separately, there was no benefit."
Secondly, Brilinta needs to be taken twice a day to maintain its effect, not once daily as with Plavix.
"No matter how good you are about medicines, you're going to miss some," Garratt.
This, added to the fact that the drug stops working if you stop taking it, means that a person who forgets his or her medication at night could see their risk for heart trouble rise by the morning.
"When it's morning again, you not only have made new platelets [which happens continuously] but the old platelets are springing back to life and people are most likely to form blood clots in the early morning hours," Garratt said. "I'm a little concerned about a drug that could leave a patient really unprotected in the early morning hours when they're most likely to form blood clots if they miss the evening dose, which will happen."
There's more on anti-clotting agents at the American Heart Association.
SOURCES: Christopher P. Cannon, M.D., cardiologist, Brigham and Women's Hospital, and associate professor, medicine, Harvard Medical School, Boston; Kirk Garratt, M.D., clinical director, interventional cardiovascular research, Lenox Hill Hospital, New York City; Jan. 13, 2010, news statement, Sanofi-Aventis U.S.; Jan. 14, 2010, The Lancet, online