A Connecticut pharmaceutical company has been hit with its second class action lawsuit in as many months over claims it defrauded stockholders with shady sales practices and by falsely hyping the growth of its drug Soliris, a treatment that costs $455,000 a year.

The Boston Retirement System filed the federal lawsuit in New Haven Dec. 29 on behalf of thousands of investors against Alexion Pharmaceuticals Inc. The federal securities class action is being brought on behalf of anyone who purchased Alexion securities between Feb. 10, 2014, and Dec. 9, 2016.