Intermittent high-dose intravenous interferon alpha 2b (IFNa2b) for adjuvant treatment of stage III malignant melanoma: Final analysis of a randomized phase III DeCOG-trial (NCT00226408).

Abstract

8505 Background: Adjuvant high-dose interferon (HDI) treatment of patients (pts) with malignant melanoma (MM) usually consists of 4 weeks initial intravenous (iv) infusion of 20 MU/m² IFNa2b followed by 11 months of 10 MU/m² subcutaneously (sc). It is still unclear, whether both components are necessary for the efficacy of HDI in high-risk MM pts. The adjuvant phase III DeCOG MM-ADJ-5 trial evaluates efficacy, safety, tolerability and quality of life (QoL) of an intermittent (pulsed) high-dose iv IFNa2b regimen as compared to standard HDI. Methods: Patients with stage III (AJCC 2002) resected intransit or lymph node metastasis from cutaneous malignant melanoma were randomly assigned to receive either standard HDI regimen (Arm A), or 3 courses of IFNa2b 20 MU/m² iv on 5 days a week for 4 weeks repeated every 4 months (Arm B). Distant metastasis free survival (DMFS) was the primary endpoint for efficacy analysis. The EORTC QLQ C30 questionnaire was used before and during the study in a standardized way (weeks 0, 4, 16, 24, 40). In addition, patients completed a diary containing global QoL measures every week. Results: Out of 649 patients who were enrolled, 22 patients had to be excluded from the intent-to-treat analysis. The remaining 627 patients were well balanced between both arms according to sex, age, and stage. Median follow-up was similar in both groups (55.4 vs. 55.3 months). Distant metastasis occurred in 138 (Arm A; 44%) vs. 145 (Arm B; 47%) patients without statistical significance (p=0.46). Survival was not significantly different for DMFS (HR 1.1; p=0.39) or OS (HR=1.0; p=0.85). Termination of treatment due to adverse events or QoL related reasons occurred significantly more often in arm A than in arm B (26.0% vs. 14.8%; p<0.001). The pulsed schedule resulted in less cumulative toxicity as compared to the standard regimen, in particular regarding fatigue and neuropsychiatric side effects. Conclusions: The final analysis of pulsed adjuvant HDI treatment showed no significant DMFS or OS differences in comparison to conventional HDI. There is a clearly favorable safety and QoL profile of the pulsed regimen.