Monday, Eli Lilly & Company and Daiichi Sankyo Company announced that they had earned European approval for their blood-thinning drug Efient, which is also known as prasugrel.

The two companies stated that their drug had won approval for heart patients suffering from acute coronary syndrome, who are undergoing an artery-opening procedure.

Efient is aimed at decreasing the platelets’ capacity to stick or bundle up together, which can result in arteries clogging, which in its turn could lead to a heart attack.

This February, prasugrel received unanimous support from an advisory panel to the United States Food and Drug Administration.

Lilly and Daiichi have been waiting for an answer from the FDA for over a year now, while federal health officials have delayed making a decision twice within that time-frame.

Now, with the drug having been approved, it will go head-to-head with Bristol Myers Squibb Company’s and Sanofi-Aventis’ Plavix.

A study conducted by Lilly and Daiichi showed that Efient prevented more cardiovascular-related deaths and heart attacks than competitor Plavix, but it also increased the risk of causing major bleeding.

When word of that issue got out, to Eli Lilly and Company’s shares dropped by over 2 percent, with investors having voiced their worries that safety issues might come to limit the use of the drug and thus hinder the product to gain market share.