ThaDD-V Treatment for Patients with Relapsed/Refractory Multiple Myeloma: A Feasibility/Activity Study.

ThaDD regimen has provided significant results in recurrent/relapsed multiple myeloma (MM) patients (Offidani et al, 2006). In order to further improve those results without significantly increasing toxicity, we decided to include Velcade, synergic as per activity but not toxicity with the other drugs of ThaDD regimen. ThaDD-V was scheduled as follows: Thalidomide 100 mg/day, pegylated liposomal Doxorubicin 30 mg/sm iv days 4; Dexamethasone 20 mg days 1–2, 4–5, 8–9, 11–12 and Velcade 1.3 mg/sm iv days 1, 4, 8, 11 every 28 days (induction therapy). Patients received bortezomib for alternate cycles as following: 1 mg/sm day 1, 8, 15 and dexamethasone 20 mg days 1–2, 8–9, 15–16 and thalidomide 100 mg/day and dexamethasone 40 mg/day for 4 days monthly for a total of six cycles as consolidation therapy. Then patients received thalidomide 100 mg/day until relapse (maintenance therapy). Actually 20 patients (7 M, 13 F; median age 62.5 yrs, range 31–75) are assessable for response and toxicity. Five pts (25%) showed WHO performance status (PS) > 1, 9 pts (45%) presented refractory disease, 8 pts (40%) were priorily administered ≥ 2 lines of a treatment and 14 patients (70%) were submitted to one previous autologous stem cell procedure. Seven patients (35%) had extramedullary disease and 7 had unfavourable cytogenetics. Twelve patients scored an ISS ≥ 2 and 11 (55%) were in first remission for ≤ 12 months median duration. No patients were previously treated with Velcade, whereas six patients had received short-term Thalidomide treatment. Response was assessed according to IMVG uniform response criteria. Seventeen of 20 patients responded after at least one chemotherapy cycle reporting 5 (25%) sCR, 3 CR (15%), 8 VGPR (40%) and 1 stable disease. Three patients (15%) had extramedullary progressive disease. In a median follow-up of 12 months, 2 (10%) patients progressed and 1 (5%) died from cardiac infarction. Time to progression and overall survival were 73% and 95% at 12 months. We observed 4 grade 3 thrombocytopenia, 2 grade 3 DVT, 1 grade 3 diarrhoea, 1 grade 3 asthenia, 1 grade 4 infection and 1 grade 3 dermatological toxicity. Six patients developed grade 2 peripheral neuropathy and other three grade 3. In conclusion, ThaDD-V is extremely active in advanced MM patients as demonstrated by the elevated precentage of high quality remission. Nevertheless, patients are at substantial risk of developing neurotoxicity so the protocol was amended as per Velcade dose intensity and Thalidomide dose.