Adjuvant therapy with pegylated interferon alfa-2b (36 months) versus low-dose interferon alfa-2b (18 months) in melanoma patients without macrometastatic nodes: an open-label, randomised, phase 3 European Association for Dermato-Oncology (EADO) study.

AIM: Both low-dose interferon (IFN) alfa-2b and pegylated interferon (Peg-IFN) alfa-2b have been shown to be superior to observation in the adjuvant treatment of melanoma without macrometastatic nodes, but have never been directly compared. Peg-IFN facilitates prolongation of treatment, which could provide additional benefit. This multicentre, open-label, randomised, phase 3 trial compared standard low-dose interferon IFN and prolonged treatment with Peg-IFN.

PATIENTS AND METHODS: Patients with resected melanoma ≥1.5mm thick and without clinically detectable node metastases were randomised 1:1 to treatment with IFN 3 MU subcutaneously (SC) three times weekly for 18 months or Peg-IFN 100 μg SC once weekly for 36 months. Sentinel lymph node dissection (SLND) was optional. The primary endpoint was disease-free survival (DFS). Secondary endpoints included distant metastasis-free survival (DMFS), overall survival (OS) and adverse events (AEs) grade 3-4.

RESULTS: Of 898 patients enrolled, 896 (443 Peg-IFN, 453 IFN) were eligible for evaluation (median follow-up 4.7 years). SLND was performed in 68.2% of patients. There were no statistical differences between the two arms for the primary outcome of DFS (hazard ratio [HR] 0.91, 95% confidence interval [CI] 0.73-1.15) or the secondary outcomes of DMFS (HR 1.02, 95% CI 0.80-1.32) and OS (HR 1.09, 95% CI 0.82-1.45). Peg-IFN was associated with higher rates of grade 3-4 AEs (47.3% versus 25.2%; p<0.0001) and discontinuations (54.3% versus 30.4%) compared with IFN.

CONCLUSION: This trial did not show superiority for adjuvant Peg-IFN over conventional low-dose IFN in melanoma patients without clinically detectable nodes. ClinicalTrials.gov identifier: NCT00221702.