US-based AbbVie has signed an agreement to acquire biopharmaceutical firm Pharmacyclics in a deal worth $21bn.
Under the terms of the transaction, AbbVie will pay 261.25 per share from a mixture of cash and equity.
The deal will allow AbbVie to acquire Pharmacyclics’ haematologic malignancies treatment Imbruvica (ibrutinib), in addition to enhancing clinical and commercial expertise in oncology.
AbbVie chairman and CEO Richard Gonzalez said: "The addition of Pharmacyclics’ talented and innovative team will add enormous value to AbbVie.
"Its flagship product, Imbruvica, is not only complementary to AbbVie’s oncology pipeline, it has demonstrated strong clinical efficacy across a broad range of hematologic malignancies and raised the standard of care for patients."
The deal was approved by both firms board of directors, and will include around 58% cash and 42% AbbVie common stock.

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By GlobalDataThrough a second-step merger, AbbVie will acquire all remaining shares of Pharmacyclics’ common stock that are not tendered in the tender offer. It will be completed immediately following the tender offer and without a vote of Pharmacyclics’ stockholders.
Pharmacyclics chairman and CEO Bob Duggan said: "We share a common purpose. Together and as one, our focus remains to create a remarkable difference for patient betterment around the world."
Bruton’s tyrosine kinase (BTK) inhibitor Imbruvica received approval for four indications to treat three different types of blood cancers, including chronic lymphocytic leukemia, mantle cell lymphoma and Waldenstrom’s macroglobulinemia.
Having obtained initial approval from the US Food and Drug Administration (FDA) in 2013, Imbruvica is the only therapy that obtained three breakthrough therapy designations from FDA.
The cancer drug is currently approved in around 40 countries, according to AbbVie.
Subject to customary closing conditions, including regulatory approvals, the transaction is expected to be completed in the middle of this year.