Incyte and Calithera Biosciences inked a global collaboration and licensing deal to develop and commercialize the latter’s early clinical-stage small-molecule arginase inhibitor CB-1158. Incyte will pay Calithera $45 million upfront and will make an $8 million equity investment in the company, in return for global rights to CB-1158 for applications in hematology and oncology. Calithera retains certain rights covering research, development, and commercialization of arginase inhibitors for other orphan indications.
CB-1158 is a metabolic checkpoint inhibitor targeting the immunosuppressive enzyme arginase in myeloid-derived suppressor cells that are responsible for T-cell suppression. Calithera claims CB-1158 could have potential antitumor activity in a range of cancers, including renal cell, breast, non-small-cell lung, acute myeloid leukemia, and other tumor types. CB-1158 is currently being evaluated in a dose-escalating monotherapy trial, and additional clinical studies are expected to investigate the drug in combination with immuno-oncology agents, including anti-programmed cell death protein-1 (PD-1) therapy.
Under terms of the deal with Incyte, the firms will jointly carry out and fund development of CB-1158, with Incyte shouldering 70% of the development costs. Incyte will also be eligible for 60% of profits or losses resulting from future approval or commercialization in the U.S., and Calithera could receive over $430 million in development, regulatory, and commercialization milestones, plus royalties on ex-U.S. sales.
Calithera also retains the option to pull out of co-funding CB-1158 development, in which case it would lose rights to U.S profits and losses, but would instead receive up to $750 million in milestones, plus tiered sales royalties and reimbursed prior development costs.
“Arginase-expressing tumor-infiltrating myeloid cells have been shown to play an important role in orchestrating the immune suppressive microenvironment in cancer; but, to date, therapeutic targeting of the arginase enzyme has remained elusive,” said Reid Huber, Ph.D., Incyte’s CSO. “The addition of this first-in-class, small-molecule arginase inhibitor CB-1158 to our portfolio expands our innovative immuno-oncology pipeline and allows us to continue to advance our mission of discovering and developing immune-active combination therapies to treat patients with cancer.”
Calithera’s lead candidate CB-839 is a glutaminase inhibitor undergoing Phase I evaluation in solid tumors. Positive data from a Phase I study evaluating C-839 in combination with paclitaxel in taxane-refractory patients with triple-negative breast cancer was reported last month.
The agreement between Calithera and Incyte represents the latter's second collaboration within the last 6 weeks. In late December 2016, the firm reported teaming up with Netherlands-based Merus to develop bispecific antibodies based on the Merus Biclonics® platform.