 New York, New York--Newsfile Corp. - March 19, 2021 - WHY: Rosen Law Firm, a global investor rights law firm, announces the filing of a class action lawsuit on behalf of purchasers of the securities of BELLUS Health Inc. NASDAQ: BLU between September 5, 2019 and July 5, 2020, inclusive the Class Period. A class action lawsuit has already been filed. If you wish to serve as lead plaintiff, you must move the Court... 