Treatment of metastatic melanoma with combined chemotherapy containing cisplatin, vinblastine and dacarbazine (CVD) and biotherapy using interleukin-2 and interferon-alpha.

BACKGROUND

Metastatic melanoma is commonly treated with chemotherapy and/or biological agents used separately. In this study we have investigated the efficacy of combined chemotherapy using cisplatin, vinblastine, DTIC (CVD) and biological therapy using interleukin-2 (IL-2) and interferon-alpha (IFN-alpha) in patients with metastatic melanoma.

PATIENTS AND METHODS

All patients had advanced, inoperable melanoma without prior treatment with chemotherapy or biotherapy, a performance status of ECOG 0-2 and no evidence of symptomatic brain metastases. The CVD regimen consisted of cisplatin 20 mg/m2/d x 4, vinblastine 1.6 mg/m2/d x 5 and DTIC 800 mg/m2 x 1, repeated at 21-day intervals. The biotherapy regimen included IL-2, 9 x 10(6) IU/ m2/d x 4 days and IFN-alpha 5 x 10(6) U/m2/d SC x 5 days. The CVD and biotherapy regimens were integrated initially, in an alternating manner at 6-week intervals and subsequently, in a sequential fashion where patients were randomized to receive either CVD immediately followed by biotherapy (CVD/Bio) or the reverse sequence (Bio/CVD). Patients were admitted to the hospital for IL-2 administration and for monitoring and treatment of IL-2 induced side effects. The phase II results of the integrated therapy (biochemotherapy) studies were retrospectively compared to our previously reported results with the CVD regimen used alone.

RESULTS

The alternating biochemotherapy program was used in 40 patients and the sequential biochemotherapy was used in 62 patients. The alternating regimen produced 2 CRs and 11 PRs for an overall response rate of 33% among 39 evaluable patients. The sequential biochemotherapy produced 14 CRs and 23 PRs for an overall response rate of 60% (95% CI, 47% to 72%). The sequence of CVD/Bio resulted in a higher response rate (11 CRs + 11 PRs (69%)) compared to the Bio/CVD sequence (3 CRs + 12 PRs (50%)). Although the duration of PRs was short (median, 8 months), the median duration of CRs was 3+years and 10 of 16 CRs are currently disease free for periods of 3+ to 6+ years. The median survival of patients receiving sequential biochemotherapy was 13 months compared to 9 months for the CVD treated group (P = 0.04). Treatment with biochemotherapy was associated with severe toxicity including intense myelosuppression, infections, IL-2 induced constitutional toxicity and hypotension. However, the IL-2 induced toxicities were generally manageable on a regular ward, except for 15% of the patients who required transfer to an intensive care unit for treatment of complications associated with the treatment.

CONCLUSIONS

The sequential combination of CVD with IL-2 + IFN-alpha appears to have produced an increase in the number of durable responses in patients with metastatic melanoma. The toxicity of this program, although severe, was manageable. The biochemotherapy regimen produced an apparent increase in the median survival compared to that observed with the CVD regimen. However, a prospective comparison of these two regimens will be required to confirm these observations.