Phase II multicentre study of temozolomide in combination with interferon alpha-2b in metastatic malignant melanoma

Temozolomide is a novel oral alkylating agent, active against metastatic melanoma. Combinations of chemotherapy and biological response modifiers have been associated with increased antitumour activity. A multicentre phase II study was performed to assess the activity and toxicity of temozolomide in combination with interferon alpha-2b.

Eligible patients had histologically confirmed metastatic melanoma. Previously untreated patients received temozolomide administered orally at a dose of 150 mg/m/day for 5 days every 4 weeks, in combination with interferon given continuously subcutaneously twice a week at a dose of 10 MU/m. Treatment continued until disease progression or for a maximum of 12 months.

From June 1999 to August 2002, 27 eligible patients were included in the study at six centres. Median age was 59 (28-77) years; 17 male and 10 female patients were recruited; the median Karnofsky performance score was 90 (70-100); three patients had received prior adjuvant interferon; the majority of patients had fewer than three involved sites. A total of 96 cycles were administered; there were one complete response, four partial response and five stable disease (overall response rate: 18.5%, 95% confidence interval: 6.3-38.1). All responses were seen in patients with exclusively lymph node and pulmonary disease [M1a (one patient); M1b (four patients)]. The median response duration was 6.9 months. One patient remains in complete remission at 4 years. The median time to progression and the median survival were 1.87 and 9.5 months, respectively. Haematological toxicity was neutropenia G-IV: 1, G-III: 4, thrombocytopenia G-III: 2, and anaemia G-III: 2. Predominant non-haematological toxicity was hepatotoxicity G-III: 4. Other toxicities were mild or moderate. Dose reduction was required for nine cycles of interferon, one of temozolomide and two of both drugs.

Temozolomide in combination with interferon is a well-tolerated palliative regimen that has moderate activity against metastatic melanoma. Further evaluation of this regimen in comparative studies or in combination with other drugs is warranted.