MacroGenics presents results from dose expansion study of tebotelimab

MacroGenics announced updated results from a dose expansion study of tebotelimab, an investigational, bispecific PD-1 LAG-3 DART molecule, in patients with diffuse large B-cell lymphoma. The data were presented at the 62nd Annual Meeting of the American Society of Hematology taking place December 5-8, 2020. LAG-3 has been shown to be highly expressed in DLBCL and has emerged as a therapeutic target of interest in this population, while PD-1-targeted therapy has yielded modest efficacy. There remains significant unmet need for patients with relapsed/refractory DLBCL. In one of the tebotelimab monotherapy dose expansion cohorts, 20 DLBCL patients were enrolled, half of whom were CAR T cell therapy experienced. As of the October 23, 2020 data cut-off, there were 13 response-evaluable patients. A preliminary objective response rate of 53.8% was observed, including responses in five of seven CAR T cell-naive patients and in two of six CAR T cell experienced patients, the latter of whom both had complete responses. A preliminary duration of response of up to 168 days was observed, with six of seven ongoing responses as of the cut-off date. In the study, baseline LAG-3 expression appeared to associate with clinical response, with additional analyses ongoing. Tebotelimab was generally well-tolerated among heavily pre-treated R/R DLBCL patients, with manageable infusion-related reactions and no evidence of tumor lysis syndrome. The most common TRAE was pyrexia, which occurred in three patients. A single Grade 3 TRAE of anemia was observed.