The oral combination of thalidomide, cyclophosphamide and dexamethasone (ThaCyDex) is effective in relapsed/refractory multiple myeloma

We evaluate the efficacy of the oral combination of thalidomide, cyclophosphamide and dexamethasone (ThaCyDex) in 71 refractory/relapsed multiple myeloma patients, including a prognostic analysis to predict both response and survival. Patients received thalidomide at escalating doses ( 200 - 800 mg/ day), daily cyclophosphamide ( 50 mg/ day) and pulsed dexamethasone ( 40 mg/ day, 4 days every 3 weeks). On an intention-to-treat basis and using the EBMT response criteria, 2% patients reached complete response (CR), 55% partial response (PR) and 26% minor response (MR) yielding a total response (CR+PR+MR) rate of 83% after 3 months of therapy. After 6 months of therapy, responses were maintained including a 10% CR. The 2-year progression free and overall survival were 57 and 66%, respectively. A favorable response was associated with beta(2) microglobulin less than or equal to4 mg/dl, platelets >80 x 10(9)/l and nonrefractory disease. Regarding survival, low beta(2) microglobulin (less than or equal to4 mg/dl), age (less than or equal to65 years) and absence of extramedullary myelomatous lesion were associated with a longer survival. Major adverse effects included constipation (24%), somnolence (18%), fatigue (17%) and infection (13%). Only 7% of patients developed a thrombo-embolic event. ThaCyDex is an oral regimen that induces a high response rate and long remissions, particularly in relapsing patients with beta(2) microglobulin less than or equal to4 mg/dl and less than or equal to65 years.