Background Glioblastoma (GBM) is a poor prognosis malignant grade 4 glioma. After surgical resection, standard therapy consists of concurrent radiotherapy (RT) and temozolomide (TMZ) followed by TMZ alone. The DC vaccination increased the amount of intratumoral-activated cytotoxic T lymphocytes and decreased the number of FoxP3-positive regulatory T cells. Based on these da-ta, we have developed a phase II protocol with the DC vaccine concomitant to standard RT-CT in patients undergoing surgery for GBM. Methods This is a single-arm, monocentric, phase II trial evaluating progression-free survival (PFS) and the safety of a DC vaccination integrated with standard therapy in resected GBM patients. The vaccine administration begins at the end of the RT-CT (Induction Phase) and is subsequently al-ternated with TMZ cycles (Maintenance Phase). The primary endpoints are PFS and safety. Among the secondary endpoints, are the in vitro and in vivo Immune response evaluations. Results By December 2022 , nine patients had been enrolled in the first step. Two patients progressed within three months after leukapheresis and none had experienced DC vaccine-related G3-4 tox-icity. Five patients had a positive DTH test against KLH. By June 2023. The median OS from leu-kapheresis was 23.1 months and 24.7 from surgery. Conclusions This combination therapy is well-tolerated, and we have achieved the two endpoints required for the first step. Therefore, the study will proceed to enroll the remaining 19 patients.