Adaptimmune and GSK expanded their June 2014 strategic collaboration to accelerate development of NY-ESO SPEAR T-cell therapy toward registration trials in synovial sarcoma and exploration in MRCLS. Under the expanded terms, Adaptimmune was eligible for up to ~$500M in incremental development milestones for NY-ESO program alone if GSK exercised its option and successfully developed in multiple indications/HLA types. GSK retained option rights pending Phase 1 data review.