PD-1 Inhibition-Trouble for Subsequent TIL Therapy in Patients with Melanoma?

To explore the lower efficacy of adoptive cell transfer (ACT) therapy in patients with anti-PD-1 experienced melanoma, tumor mutational burden (TMB), predicted neoantigen frequencies, and tumor-infiltrating lymphocyte (TIL) neoantigen reactivity were assessed. Reduced neoantigen-specific TIL frequencies correlated with lower ACT response even in patients with similar TMB, suggesting a potentially harmful effect of PD-1 inhibition on T-cell outgrowth. See related article by Levi et al., p. 3042.