Early surgical intervention remains the most successful therapy for melanoma. Despite better outcomes observed in soft tissue and lymph node metastases, the results of pharmacological therapies are still disappointing. Currently, there is no standard adjuvant therapy for melanoma. Low concentrations of coenzyme Q10 have been demonstrated in melanoma cell lines and in sera of melanoma patients. These data and the results of clinical trials of patients with other advanced cancers prompted this study of the long-term administration of an optimized dose of recombinant interferon alpha-2b and coenzyme Q10 to patients with stage I and II melanoma. A 3-year trial envisaging uninterrupted treatment with low-dose recombinant interferon alpha-2b (9 000 000 000 IU weekly) administered twice daily and coenzyme Q10 (400 mg/day) was conducted in patients with stage I and II melanoma (American Joint Committee on Cancer criteria 2002) and surgically removed lesions. Treatment efficacy was evaluated as incidence of recurrences at 5 years. All patients completed the treatment and the follow-up. Significantly different rates of disease progression were observed in the interferon+coenzyme Q10 and the interferon group for both stages. No patient withdrew from the study owing to side effects. Long-term administration of an optimized dose of recombinant interferon alpha-2b in combination with coenzyme Q10 seemed to induce significantly decreased rates of recurrence and had negligible adverse effects. A survival study could not be undertaken owing to the small patient sample and the short duration of follow-up.