We have previously shown that vaccination with tumor-pulsed dendritic cells amplifies neoantigen recognition in ovarian cancer. Here, in a phase 1 clinical study (NCT01312376/UPCC26810) including 19 patients, we show that such responses are further reinvigorated by subsequent adoptive transfer of vaccine-primed, ex vivo-expanded autologous peripheral blood T cells. The treatment is safe, and epitope spreading with novel neopeptide reactivities was observed after cell infusion in patients who experienced clinical benefit, suggesting reinvigoration of tumor-sculpting immunity.

Coukos and colleagues conduct a phase 1 study to evaluate the benefit of adoptive transfer of ex vivo-expanded, vaccine-primed T cells in patients with ovarian cancer-a cancer type that often does not respond to immune checkpoint blockade.