Intravenous melphalan, thalidomide and prednisone in refractory and relapsed multiple myeloma

Thalidomide combined with conventional chemotherapies including oral melphalan shows significant anti-myeloma activity. To address this issue, feasibility and efficacy of a three drug combination consisting of intravenous (i.v.) melphalan, thalidomide and prednisone [M(i.v.)PT] was evaluated in advanced myeloma patients.

Twenty-four advanced myeloma patients were treated with multiple cycles of a regimen consisting of low dose i.v. melphalan (20 mg/m2) at d 1, thalidomide at the dose of 50-100 mg/d given continuously and oral prednisone at the planned dose of 50 mg/d every other day. Intravenous melphalan was administered every fourth month. Median time from diagnosis was 40 months (range: 8-144 months). Fifteen patients (66%) had previously been treated with a combination of thalidomide and dexamethasone or with thalidomide alone.

Overall, on an intent-to treat basis, 14 patients responded: three achieved near complete remission (nCR), seven achieved partial response (PR), four minimal response (MR). Six patients showed stable disease (SD) and four-disease progression. Interestingly, of five patients who had previously progressed while on thalidomide and prednisone, one reached nCR, two PR and one MR. After a median follow up of 14 months, median progression free survival was 9 months. Response duration was longer than that induced by the previous line of treatment in eight patients (33%). Thalidomide-associated toxicity mainly consisted of constipation, tingling and sedation.

M(i.v.)PT is an effective regimen, which can overcome resistance to thalidomide plus prednisone in advanced myeloma with acceptable toxicity.