A pilot study of peripheral blood BDCA-1 (CD1c) positive dendritic cells pulsed with NY-ESO-1 ISCOMATRIX™ adjuvant

Aim: Pilot clinical trial of NY-ESO-1 (ESO) protein in ISCOMATRIX™ adjuvant pulsed onto peripheral blood dendritic cells (PBDC), to ascertain feasibility, evaluate toxicity and assess induction of ESO-specific immune responses. Patients & methods: Eligible participants had resected cancers expressing ESO or LAGE-1 and were at high risk of relapse. PBDC were produced using CliniMACS®plus, with initial depletion of CD1c+ B cells followed by positive selection of CD1c+ PBDC. Patients received three intradermal vaccinations of ESO/IMX-pulsed PBDC at 4-week intervals. Results: The process was feasible and safe. No vaccine-induced immune responses were detected. Assays of immunomodulatory cells did not correlate with outcomes. One patient had a long lasting complete remission. Conclusion: This method was feasible and safe but was minimally immunogenic.