Mallinckrodt to Buy Immunotherapy Firm Therakos

Mallinckrodt PLC said Monday that it would buy privately-held immunotherapy company Therakos Inc. for about $1.325 billion, the latest deal for the acquisitive pharmaceutical company.

Dublin-based Mallinckrodt, which was spun off from Covidien PLC in 2013, said the purchase is a move to grow its hospital business within its specialty brands portfolio. The company, like many others in the space, has sought to grow through acquisitions. Recent acquisitions include privately held Ikaria Inc. for about $2.3 billion, Questcor Pharmaceuticals Inc. for $5.8 billion and Cadence Pharmaceuticals Inc. for $1.3 billion.

Those deals have fueled sales, particularly within the specialty brand segment, where revenue in Mallinkrodt's June quarter nearly quintupled from a year earlier and offset sales declines in its other segments.

Therakos, which specializes in treatments that use patients' own immune systems to fight disease, is a former unit of a Johnson & Johnson subsidiary and in 2009 won U.S. regulatory approval for its photopheresis systems for the treatment of cutaneous T-cell lymphoma in patients for whom other forms of treatment haven't worked. The treatment is used by academic medical centers, hospitals and treatment centers in about 25 countries, Mallinckrodt said.

Mallinckrodt, which expects to complete the transaction late in the third quarter, said the deal would add at least 10 cents a share to adjusted earnings for its 2016 business year. The company expects Therakos to report $185 to $195 million in 2015 sales and sees high single-digit sales growth going forward.

Shares in the company, down 19% this month after revenue growth in its latest quarter missed analysts' expectations, were inactive premarket.

Write to Lisa Beilfuss at [e-mail]

Subscribe to WSJ: http://online.wsj.com?mod=djnwires