Pfizer Inc. has joined with San Diego-based private biotech eFFECTOR Therapeutics Inc. to develop small-molecule inhibitors of a certain protein that is activated in a number of human cancers.

The collaboration will focus on the development of small-molecule inhibitors of eukaryotic initiation factor 4E, a protein that resists certain cancer treatments and is linked to poor prediction of the disease.

Under the exclusive worldwide license and collaboration agreement, Pfizer will pay eFFECTOR $15 million upfront and up to an additional $492 million in potential development and sales milestone payments.

Additionally, eFFECTOR will receive royalties on sales of any products from the program that reaches the commercialization stage.