The US Food and Drug Administration (FDA) has given permission to pharmaceutical company AstraZeneca to provide long-term use of its blood thinner Brilinta in patients having a history of heart attacks.

The new dose approved by the FDA is of 60 mg, which can now be used by patients beyond the first year to prevent blood clots that can cause heart attacks, strokes and deaths. The approval is expected to double the number of patients taking the medicine and also to strengthen the company's chances of making revenue. The company expects that Brilinta's sales could reach $3.5 billion by 2023.

The permission was received after seeing the results of clinical trial in which more than 21,000 patients were involved. There are some analysts who have casted doubts, as some patients developed suicidal thoughts during clinical trials to treat psoriasis.

As per the company, the new 60mg dose of Brilinta will be available in the market by end of this month. Joseph Fuhr, a professor of economics at Widener University, affirmed that for now, it is not known whether a patient facing suicidal thoughts could file litigation against AstraZeneca.

"You can sue anyone for anything. AstraZeneca can always contend that it didn't market the drug. You never know how a jury is going to decide", affirmed Fuhr.

Brilinta vice-president Tom Keith-Roach was of the view that the new dose will help strong and consistent growth over time.