Interferon-alfa (IFN) is still a standard and most widely used adjuvant therapy for patients (Pts) with skin melanoma. Nevertheless, the efficacy of this approach is doubtful despite decades of clinical trials. CaTeVac is autologous DC, derived from peripheral mononuclear cells of the patient, loaded with lysate of allogenic melanoma cell lines with high expression of cancer-testis antigens. We compared cohort of Pts receiving adjuvant therapy with CaTeVac with a cohort of consecutive Pts in our center who received IFN in the adjuvant setting.
Pts with morphologically proven melanoma received CaTeVac or IFN. CaTeVac was injected subcutaneously in doses from 5 to 20*106 cells per cycle (C.) in the following regimen: C.1 – 14 days, C.2-4 – 21 days, C.5-14 – 30 days. After a year of the therapy Pts were allowed to receive additional cycles: C.15-18 (3 mo each) and C.19-20 (6 mo each). Each C. consisted from cyclophosphamide 300 mg injection on day 1 and CaTeVac injection on day 4. Pts in control group received IFN until progression, toxicity or at least 1 year of therapy whatever comes first. Both groups of patients were followed with the same clinical and laboratory methods and in the same time intervals.
Ninety Pts treated from 2009 to 2016 were included in the study: 48 received CaTeVac, 42 – IFN (2-high doses of IFN, 36 – low doses of IFN, 4 – IFN with dose escalation from 3 MIU until maximum tolerated dose achieved). Median of follow-up was 23 mo. Patients with stage III and IV were presented more often in CaTeVac group (79,2% and 20,8%) when compared to IFN group (68% and 4%, respectively). Stage I-II patients composed 28% of IFN group, none were in CaTevac group; X2 test for stage p = 0,001. Median time to progression in CaTeVac was 11,4 mo, for IFN group - 6,9 mo (p = 0,097). Two-year progression-free survival was 42% and 17% for CaTeVac and IFN, respectively. Relative risk for progression in 2 years was 0,74 (95% CI 0,57-0,96) for CaTeVac. Median of overall survival was 79,8 mo in IFN group and was not reached in CaTeVac group (p = 0,352) with plateau at 58% after 41 months.
Rather promising results received in our study justify performing of randomized trials with CaTeVac versus IFN in adjuvant setting for patients with melanoma.
Clinical trial identification
Legal entity responsible for the study
N.N. Petrov Research Institute of Oncology
A. Novik, S. Protsenko: Lector for MSD, Bristol-Myers Squib, Roche, Novartis. All other authors have declared no conflicts of interest.