Blackstone Life Sciences Becomes Sole Owner of Anthos

Blackstone Life Sciences has announced on Tuesday that it has signed an agreement with Swiss multinational pharmaceutical corporation Novartis to acquire Anthos Therapeutics (Anthos), a transformative, clinical-stage biopharmaceutical company developing innovative therapies for the treatment of cardio metabolic diseases, for $3.1 billion.

Anthos was founded by Blackstone Life Sciences and Novartis in 2019 with the exclusive global rights from Novartis to develop, manufacture, and commercialize Abelacimab, a novel factor XI inhibitor that originated at Novartis, being developed to prevent stroke and systemic embolism in patients with atrial fibrillation as well as to prevent the recurrence of blood clots in patients with cancer. 

in 2019 with the exclusive global rights from Novartis to develop, manufacture, and commercialize Abelacimab, a novel factor XI inhibitor that originated at Novartis, being developed to prevent stroke and systemic embolism in patients with atrial fibrillation as well as to prevent the recurrence of blood clots in patients with cancer. 

Anthis CEO Bill Meury said that Abelacimab has the potential to be an important treatment option for the millions of patients globally with atrial fibrillation at high risk of stroke, and they could not have more conviction in the potential of this asset.

He said that with its deep roots in the cardiovascular space, Novartis is especially well positioned to advance Abelacimab’s clinical development and bring this innovative product to healthcare providers and patients.

“I am grateful to the Anthos and Blackstone Life Sciences teams, the clinical investigators, the patients in our studies, the advocacy community, and many others who have played a role in Anthos’ success over the past six years,” Meury added.

Dr Nicholas Galakatos, Chairman of Anthos and Global Head of Blackstone Life Sciences said that they were proud to have launched and helped grow Anthos by acquiring the rights to Abelacimab, assemble a world class team, design the clinical plan and finance its development.

He also said that Abelacimab has the potential to be a leader in the new class of Factor XI anticoagulants and are pleased to have Novartis as a committed partner to advance its development and commercialisation as a potential treatment option for the millions of patients at risk of strokes. “This transaction is an affirmation of Blackstone Life Sciences’ ownership investment strategy, where we seek to find innovative products and build companies around them to meet unmet patient needs,” he added.

The overall clinical benefit of Abelacimab prompted the Independent Data Monitoring Committee to discontinue the study early.

Anthos is currently conducting a phase 3 clinical study in patients with atrial fibrillation with high risk for stroke or systemic embolism (LILAC-TIMI 76) as well as two phase 3 studies in patients with cancer-associated thrombosis (ASTER and MAGNOLIA). Data from these trials are expected in the second half of 2026. 

Blackstone Life Sciences’ investment in and commitment to Anthos demonstrate the power of combining its scale and deep operating expertise to build businesses that can help bring innovative products to market and substantially improve patient outcomes.

Transaction Details

Anthos shareholders will receive an upfront payment of $925 million upon closing of the transaction. In addition, Anthos shareholders are entitled to receive payments in the event certain regulatory and commercial milestones are achieved.

Completion of the transaction is expected in the first half of 2025, pending the expiration of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act and satisfaction of other customary closing conditions.