Efficacy and safety of Id-protein-loaded dendritic cell vaccine in patients with multiple myeloma \u2013 Phase II study results

In a\u202fphase II clinical study, pretreated multiple myeloma patients with relapsing or stable disease received autologous anticancer vaccine containing dendritic cells loaded with Id-protein. Patients received a\u202ftotal of 6 vaccine doses intradermally in monthly intervals. No clinical responses were observed. During the follow-up with a\u202fmedian of 33.1 months (range: 11-43 months), the disease remained stable in 7/11 (64%) of patients. Immune responses measured by ELISpot were noted in 3/11 (27%) and DTH skin test for Id-protein was positive in 8/11 (73%) of patients; out of those, 1/11 (9%) and 5/11 (46%), respectively, had preexisting immune response to Id-protein before the vaccination began. Outcomes were compared to those of a\u202fcontrol group of 13 patients. A\u202ftrend to lower cumulative incidence of progression in the vaccinated group was observed at 12 months from the first vaccination (p= 0.099). More patients from the control group compared to vaccinated patients required active anticancer therapy [4/11 (36%) vs. 8/13 (62%)]. Vaccines based on dendritic cells loaded with Id-protein are safe and induce specific immune response in multiple myeloma patients. Our results suggest that the vaccination could stabilize the disease in approximately two-thirds of patients