Rappta Therapeutics, a private biotech focused on developing anti-cancer drugs activating protein phosphatase 2A (PP2A), has announced an exclusive global license agreement with SpringWorks Therapeutics for RPT04402, a first-in-class molecular glue of specific Protein Phosphatase 2A (PP2A) complexes.

Rappta’s PP2A-reactivating technologies have the potential to create a new class of anti-cancer drugs for treating a broad range of human cancers. PP2A is a critical enzyme in regulating protein de-phosphorylation, and its reactivation is fundamental for tumor suppression, but it has been historically hard to target.

PP2A mutations are oncogenic drivers in molecularly defined subsets of uterine cancer and represent a targetable subset of patients with a high unmet clinical need. In pre-clinical models of PP2A mutant uterine cancer, RPT0402 achieved rapid, deep and durable tumor regressions as monotherapy.

Under the exclusive license agreement, SpringWorks Therapeutics will be responsible for global development and commercialization of RPT04402. SpringWorks has paid Rappta $13 million upfront, and Rappta is also eligible to receive further clinical, regulatory and commercial milestone payments, and tiered single-digit royalties on net sales. SpringWorks expects to file an Investigational New Drug (IND) application for RPT04402 by the end of 2025.

Sunjeet Sawhney, CEO of Rappta Therapeutics, commented: “Rappta is the only company to have successfully targeted PP2A, a notoriously difficult and undruggable target. Data we generated demonstrated the potential of RPT04402 for treating large, underserved patient populations. SpringWorks, a leader in the targeted oncology space, has the expertise and knowledge to accelerate the further development of our first-in-class asset. I would like to thank our team and investors who have supported our journey and we look forward to following the progress made in this area.”

Goutham Narla, Chief Scientific Officer of Rappta Therapeutics and Professor of Internal Medicine and Human Genetics at the University of Michigan, said: “Our team at Rappta Therapeutics has been able to leverage our proprietary structural data to develop a first-in-class series of molecular glues to the previously undruggable tumor suppressor PP2A. We are excited to be able to work with SpringWorks to potentially translate this approach to the clinic with the hope that this approach will have broad applications for the treatment of human cancers.”