GlaxoSmithKline up-sizes its bet on Adaptimmune, racing forward with a cancer immunotherapy

GlaxoSmithKline ($GSK), working with Adaptimmune ($ADAP) on therapies that use the body's machinery to fight cancer, is sweetening the deal for its partner, promising more cash to accelerate development of a promising treatment for soft tissue sarcoma.

Under an expanded agreement, GSK is promising to fund pivotal trials for GSK3377794, an Adaptimmune-discovered immunotherapy that targets the cancer antigen NY-ESO-1.

The plan is to push the cell therapy into pivotal trials in synovial sarcoma, a cancer of the joints, and explore the idea of developing GSK3377794 in a form of liposarcoma. The new deal also gives GSK the option to sponsor up to 8 combination studies starring Adaptimmune's therapy, including trials pairing the treatment with checkpoint inhibitors, the companies said.

In exchange, GSK has boosted its potential payout from $350 million over 7 years, promised in its initial 2014 agreement with Adaptimmune, to as much as $500 million. GSK has the option to buy the NY-ESO-1 program outright once it comes through with proof-of-concept data, which would give it rights to the therapy in multiple myeloma and lung, ovarian, skin and esophageal cancers in addition to synovial sarcoma.

Adaptimmune's program is T-cell receptor, or TCR, therapy. Similar to the CAR-T therapies that have made headlines around the world, TCR treatments are designed to school a patient's T cells to seek out specific antigens expressed by tumors liquid and solid.

The promise of Adaptimmune's TCR platform helped the U.K. biotech pull off a $191 million U.S. IPO last year, and the company has since invested in a sizable R&D hub near its native Oxford, growing to employ more than 200 people.

Behind its GSK-partnered work, Adaptimmune has wholly owned TCRs targeting lung and liver cancers slated to enter clinical development this year. The company is also at work on a dozen discovery-stage projects.

- read the statement