Regeneron Inks $2.2B Deal with Parabilis to Advance Antibody-Helicon Conjugates Targeting 'Undruggable' Intracellular Proteins

On May 18, Regeneron announced a strategic research collaboration with Parabilis Medicines to discover and develop multiple candidate therapeutics based on Parabilis' Helicon™ peptide platform, with a particular focus on antibody-Helicon™ conjugates (AHCs), a novel class of therapeutics designed to target challenging and historically undruggable targets.Target.ParabilisFounded by Professor Gregory Verdine, a pioneering academic scientist from Harvard University and a successful biotechnology company builder, more than 810 million US dollars have been raised so far from leading life science investors.（$305 Million Series F Financing to Develop New Spiral Peptide Drugs）

Helicons are stable, cell-permeable α-helical peptides designed to bind to intracellular protein targets, including flat surfaces not well-suited for traditional small molecule binding. The collaboration aims to explore the use of Helicons both as standalone therapies and as part of AHCs.

George D. Yancopoulos, M.D., Ph.D., Co-Founder, President, and Chief Scientific Officer of Regeneron, said:"This collaboration reflects Regeneron's approach to advancing cutting-edge and diverse science to produce a powerful portfolio of innovative medicines for patients in need. In addition to Helicons' potential to address previously undruggable targets, this partnership aims to combine Helicons with our VelocImmune®-derived antibodies to precisely deliver them to cells of interest, representing an exciting new approach with the potential to create an entirely new therapeutic category spanning multiple treatment areas."

AntibodyConjugationDrugs traditionally use antibodies to selectively deliver drug payloads to target cells to drive cell death from within. This collaboration envisions AHC based on the same delivery principle: pairing antibody-targeted pathways with Helicon payloads to selectively modulate specific intracellular proteins, including some that have long been considered undruggable.

Under the terms of the agreement, Parabilis will receive $125 million from Regeneron in the form of a $50 million upfront payment and a commitment to invest $75 million in Parabilis’ next equity financing under certain conditions. Parabilis is also eligible to receive milestone payments for development, regulatory, and commercial achievements, as well as tiered double-digit royalties on future net sales of any approved drugs resulting from the collaboration. The agreement includes five initial targets, providing Parabilis with up to approximately $2.2 billion in potential milestone payments. Additional targets may be pursued following Regeneron’s payment for extra options under the terms of the agreement.

The agreement stipulates that the two parties will collaborate to discover new Helicons and AHCs, and Regeneron will be responsible for advancing these products through development, manufacturing, and global commercialization.