** Shares of drug developer Allakos ALLK.O rise 45.6% to 32 cents premarket

** Concentra Biosciences will buy Allakos for 33 cents per share in cash, a premium of 52% to ALLK's last close

** Allakos says a wholly owned subsidiary of Concentra will commence a tender offer by April 15 to acquire all outstanding shares of ALLK

** Co expects the deal to close in May 2025

** Says closing of the deal is subject to availability of at least $35.5 million of cash at closing, and other customary closing conditions

** Shares of the company have fallen 82.1% YTD

(Reporting by Sneha S K )

(( Sneha.SK@thomsonreuters.com))