Regeneron Pharmaceuticals, Inc. and Mammoth Biosciences, Inc. announced a collaboration to research, develop and commercialize in vivo CRISPR-based gene editing therapies for multiple tissues and cell types. Regeneron is developing adeno-associated viral vectors (AAVs) using antibody-based targeting to enhance delivery of genetic medicine payloads to specific tissues and cell types. Mammoth is developing novel ultracompact nucleases and associated gene editing systems, with a variety of editing functionalities at a significantly smaller size than other CRISPR-based systems, including first generation Cas9 nucleases.

By leveraging Regeneron?s expertise in AAV and antibody engineering and Mammoth?s expertise in ultracompact gene editing systems, the teams will endeavor to create disease-modifying medicines that can be delivered to tissues beyond the liver, to which most gene editing treatments are currently limited. Under the terms of the agreement, Mammoth will receive $100 million inclusive of $95 million in equity investment at signing, and an upfront payment, and is eligible to receive up to $370 million per target in development, regulatory and commercial milestone payments, and royalty rates ranging from single digits to mid-teens on future net sales of all collaboration products. In addition, Mammoth has the right to opt-in to co-funding and sharing profits on a majority of collaboration programs in lieu of receiving milestones and royalties.

In exchange, for a period of five and a half years, Regeneron is obtaining broad access to Mammoth?s editing technologies, other than certain excluded targets, with the option to extend such access for an additional two years upon the payment of a research extension fee. The parties will jointly select and research collaboration targets, and then Regeneron will lead development and commercialization.