Blackstone Group Inc. (BX) and biopharmaceutical firm Alnylam Pharmaceuticals Inc. (ALNY) on Monday, April 13, unveiled a collaboration under which Blackstone will provide up to $2 billion to support the advancement of RNA interference (RNAi) medicines.

RNAi is a process whereby RNA molecules hinder the expression of disease-causing genes through the destruction of the messenger RNA of those genes.

As part of the agreement, Blackstone will pay $1 billion to purchase 50% of Alnylam’s royalties and commercial milestones for inclisiran, an investigational cholesterol treatment that became part of Novartis AG’s pipeline through its acquisition of Medicines Co. Novartis completed its $9.7 billion purchase of Medicines in January.

The collaboration deal also includes Blackstone’s $100 million purchase of Alnylam common stock, as well as up to $750 million in a first lien senior secured term loan led by Blackstone’s credit investment platform, GSO Capital Partners LP, and up to $150 million from Blackstone Life Sciences for the development of Alnylam’s cardiometabolic programs vutrisiran and ALN-AGT.

“Our collaboration with Alnylam provides non-dilutive access to capital to advance important new medicines in development across several disease indications including heart disease, the leading cause of death in the U.S. and globally,” said Nicholas Galakatos, global head of Blackstone Life Sciences, in the news release.

Also on Monday, Cambridge, Mass.-based Alnylam, a tenant of Blackstone Real Estate company BioMed Realty, said it is in talks with BioMed to broaden its footprint in Cambridge.

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