GSK has decided to end its five-year collaboration with Ideaya Biosciences, a move that will affect the future development of two cancer drug candidates. The termination was disclosed by Ideaya in a recent SEC filing, though no reason for GSK’s decision was provided. The partnership will officially conclude 90 days after Ideaya was notified on December 4.
BioSpace has reached out to GSK for comment on the matter.
Truist Securities analysts commented on the news, calling it “disappointing,” but stated, “we do not view this update as thesis-changing” for Ideaya’s drug pipeline. They identified darovasertib, a small-molecule kinase inhibitor being developed for uveal melanoma, as the company’s main asset. Results from Phase II/III trials are expected by the end of this year or early next year.
Ideaya expressed confidence in its financial stability despite losing GSK as a partner. In its SEC filing, the company said that the termination “does not change the expectation of cash runway into 2030.” As reported in its third-quarter results, Ideaya had approximately $1.14 billion in cash and equivalents as of September 30.
The collaboration began in June 2020 when GSK paid $100 million upfront and made an additional $20 million equity investment in Ideaya shares. The agreement included provisions for preclinical, clinical, and sales milestone payments tied to programs focused on synthetic lethality—a method that targets genetic weaknesses unique to cancer cells.
Initially, three programs were part of the deal: MAT2A, Pol Theta, and Werner Helicase. However, in August 2022 GSK ended work on MAT2A and declined an exclusive license option for IDE397—a molecule aimed at certain urothelial and lung cancers.
With last week’s announcement, rights to both Pol Theta (IDE705) and Werner Helicase (IDE275) will return to Ideaya. IDE705 is intended for tumors with BRCA or other homologous recombination mutations; IDE275 targets solid tumors exhibiting high microsatellite instability.
Ideaya now plans to consider strategic options for these two assets over the coming year. According to Truist analysts, these options may include seeking new partners or continuing development internally depending on data trends within oncology treatments.
This termination follows other significant moves by GSK in oncology. In October, GSK secured FDA approval for Blenrep as a third-line treatment for multiple myeloma despite previous negative feedback from external advisors. Earlier this year in July, GSK announced a $12 billion partnership with China’s Hengrui Pharma to develop up to 12 new treatments targeting cancer along with respiratory and immunology diseases.
