Long-term clinical outcome of melanoma patients treated with messenger RNA-electroporated dendritic cell therapy following complete resection of metastases
Melanoma patients with a high risk of recurrence may benefit from immunotherapy with mRNA-electroporated autologous monocyte-derived dendritic cells (DCs). Further benefit may be found in combining DC-therapy with interferon alfa-2b.
Patients and methods
The long-term clinical outcome of AJCC stage III/IV melanoma patients who had no evidence of disease at the time of treatment with autologous mRNA-electroporated DCs in a single-center pilot clinical trial was analyzed. Antigen loading was accomplished by co-electroporation of mRNA encoding a fusion protein between MAGE-A1, -A3, -C2, Tyrosinase, MelanA/MART-1, or gp100, and an HLA class II-targeting sequence. DCs were administered by 4–6 bi-weekly intradermal injections. IFN-α-2b (5 MIU TIW) was initiated either at recurrence (cohort 1), concomitant with DCs (cohorts 2 and 3), or following the fourth DC administration (cohort 4).
Thirty melanoma patients were recruited between April 2006 and June 2009. DC-related adverse events included grade 2 local injection site reactions in all patients, grade 2 fever and flu-like symptoms in one patient, and skin depigmentation in seven patients. After a median follow-up of over 6 years, the median relapse-free survival is 22 months (95 % CI 12–32 months). Twelve patients have died. The median overall survival has not been reached; the 2-year and 4-year survival rates are 93 and 70 %, respectively.
Adjuvant therapy following the resection of melanoma metastases with autologous mRNA-electroporated DCs, combined with interferon alfa-2b, is tolerable and results in encouraging long-term overall survival rates justifying further evaluation in a randomized clinical trial.
KeywordsDendritic cell Interferon alpha-2b mRNA Immunotherapy Melanoma
American Joint Committee on Cancer
Constitutively active Toll-like receptor 4
Cytotoxic T-lymphocyte-associated antigen 4
Granulocyte/macrophage colony-stimulating factor
Human leucocyte antigen
Mitogen-activated protein kinase
Million international units
Magnetic resonance imaging
Messenger ribonucleic acid
Positron emission tomography–computed tomography
Skin infiltrating lymphocytes
T helper type 1
Three times in a week
World Health Organization Performance Status