
Contributions
Abstract: S141
Type: Oral Presentation
Presentation during EHA22: On Friday, June 23, 2017 from 11:30 - 11:45
Location: Room N109
Background
Aims
The aim of this phase II study was to determine the clinical efficacy of dendritic cell (DC) vaccine therapy in AML, and, more specifically, whether this form of immunotherapy can be applied in the post-remission adjuvant setting to decrease the risk of relapse following chemotherapy and to improve survival.
Methods
We vaccinated 30 AML patients in remission following polychemotherapy, but at very high risk of relapse with autologous DCs loaded with the Wilms' tumor 1 (WT1) antigen by means of mRNA electroporation, a technique that allows for human leukocyte antigen haplotype-independent, multi-epitope antigen presentation to T-cells. The vaccines were administered intradermally.
Results
There was a demonstrable anti-leukemic response in 13/30 patients (overall response rate 43%). Nine patients achieved molecular remission as demonstrated by normalization of WT1 transcript levels, 5 of which are sustained after a median follow-up of 109.4 months, including 1 patient who went from partial remission to complete remission by DC vaccination only. In the remaining 4 responding patients, the clinical response was characterized by stable disease as demonstrated by elevated but stable WT1 transcript levels in blood for 3-12 months and stable blood values without blasts.
Conclusion
Vaccination of AML patients with WT1 mRNA-electroporated DCs can be an effective and non-toxic strategy to prevent or delay leukemia relapse after standard chemotherapy, translating into improved overall survival rates, which are correlated with the induction of WT1-specific CD8+ T-cell responses.
Session topic: 24. Gene therapy, cellular immunotherapy and vaccination
Keyword(s): WT1, Relapse, Dendritic cell vaccine, Acute Myeloid Leukemia
Abstract: S141
Type: Oral Presentation
Presentation during EHA22: On Friday, June 23, 2017 from 11:30 - 11:45
Location: Room N109
Background
Aims
The aim of this phase II study was to determine the clinical efficacy of dendritic cell (DC) vaccine therapy in AML, and, more specifically, whether this form of immunotherapy can be applied in the post-remission adjuvant setting to decrease the risk of relapse following chemotherapy and to improve survival.
Methods
We vaccinated 30 AML patients in remission following polychemotherapy, but at very high risk of relapse with autologous DCs loaded with the Wilms' tumor 1 (WT1) antigen by means of mRNA electroporation, a technique that allows for human leukocyte antigen haplotype-independent, multi-epitope antigen presentation to T-cells. The vaccines were administered intradermally.
Results
There was a demonstrable anti-leukemic response in 13/30 patients (overall response rate 43%). Nine patients achieved molecular remission as demonstrated by normalization of WT1 transcript levels, 5 of which are sustained after a median follow-up of 109.4 months, including 1 patient who went from partial remission to complete remission by DC vaccination only. In the remaining 4 responding patients, the clinical response was characterized by stable disease as demonstrated by elevated but stable WT1 transcript levels in blood for 3-12 months and stable blood values without blasts.
Conclusion
Vaccination of AML patients with WT1 mRNA-electroporated DCs can be an effective and non-toxic strategy to prevent or delay leukemia relapse after standard chemotherapy, translating into improved overall survival rates, which are correlated with the induction of WT1-specific CD8+ T-cell responses.
Session topic: 24. Gene therapy, cellular immunotherapy and vaccination
Keyword(s): WT1, Relapse, Dendritic cell vaccine, Acute Myeloid Leukemia