Research published earlier this week in the New England Journal of Medicine presents data showing that the anti-clotting drug rivaroxaban may change the future of post-heart attack treatment. The study was conducted by Harvard cardiologists Dr. C. Michael Gibson and Dr. Jessica Mega who both work at Brigham and Women’s Hospital.

The results showed that patients who took rivaroxaban each day after their heart attack not only had a lower risk of experiencing another one later on but also had a reduced risk of cardiovascular death compared to patients who took placebos.

A major contributing factor of later heart attacks is the accumulation of the enzyme thrombin.

“This is a chronic problem,” said co-author Gibson. “What we did was block the creation of that enzyme with an anti-thrombin drug.”

By preventing the accumulation of thrombin, rivaroxaban reduces the risk of experiencing another heart attack and, in an unprecedented occurrence in anti-clotting drug studies, reduces the risk of dying due to cardiovascular complications by thirty-eight percent.

“This is a major breakthrough,” said Gibson. “We have been working on this for many years now, and we think we have found something that will really change practice.”

However, the study did not yield only positive news.

“There is always a risk,” said Mega. “It is a double-edged sword, as there was also an increased risk of bleeding.”

Bleeding was observed in the brain and other areas of the body. Even though there were a number of serious cases of bleeding, the study’s conclusion was that most instances were not life threatening.

Rivaroxaban still awaits an approval decision by the Food and Drug Administration in order to treat post-heart attack patients in regular clinical practice. The drug has already been approved under the trade name Xarelto to treat both blood clots in the legs (deep venous thrombosis) and to prevent clots related to atrial fibrillation. However, approval for the heart attack indication hinges on assessment of benefit versus risk, primarily bleeding.

As to whether or not the drug will be approved with a cardiovascular indication, Mega is both optimistic and realistic.

“It’s always hard to say,” said Mega. “It was exciting to be a part of such clinical work, but you can never really make predictions about what gets approved or not.”

Dr. Sandeep Khosla, chief of cardiology at Mount Sinai Hospital Center in Chicago, Ill., has positive expectations for rivaroxaban.

“I am excited about the drug,” he said. “It can be taken orally as opposed to the more common injection method. I think this will be good for patients down the road.”