Multicenter phase 1 trial of intratumoral toll-like receptor 4 agonist plus radiotherapy for metastatic soft tissue sarcoma

A multicenter phase 1 trial evaluated intratumoral glycopyranyl lipid A in stable emulsion formulation (GLA-SE), a toll-like receptor 4 agonist, in combination with concurrent radiotherapy for metastatic soft tissue sarcoma. GLA-SE with radiotherapy was well tolerated, with all 12 patients achieving local control of injected tumors. Durable local response was associated with expansion of intratumoral T-cell receptor clones, and these clones were detectable in the systemic circulation following intratumoral GLA-SE. The authors conclude that intratumoral GLA-SE with radiotherapy is a promising combination for advanced soft tissue sarcoma.