Velcade (Bortezomib), Adriamycin Dexamethasone (PAD) or Vincristine Adriamycin Dexamethasone in Second Line Treatment of Multiple Myeloma

Overview

The purpose of this research study is to test the safety and effectiveness of replacing vincristine with a drug called bortezomib (also known as "Velcade"or PS341) in the standard therapy vincristine, doxorubicin (not limited to, but formerly referred to under the tradename Adriamycin) and dexamethasone (VAD) in patients with multiple myeloma. Multiple Myeloma is the second most common cancer of the blood. Bortezomib is the first approved cancer treatment in a new class of medicines called proteasome inhibitors. It disrupts the cell cycle of the cell, affecting numerous biologic pathways, including those related to growth and survival of cancer cells. The treatment will be used as second line treatment, which means either the disease has returned after a period of improvement (relapse) or the disease did not respond to the initial treatment (refractory). Patients will receive either bortezomib (PS341), doxorubicin (Adriamycin) and dexamethasone (PAD) or the VAD standard therapy.

Bortezomib, has been approved for use in patients with multiple myeloma, who have already received at least one prior treatment and whose disease is worsening on their last treatment and who have already undergone or are unsuitable for bone marrow transplantation. Bortezomib has significant activity in patients with relapsed multiple myeloma, its efficacy is increased with the addition of dexamethasone and it demonstrates synergy with doxorubicin. The VAD combination has been widely used in multiple myeloma and has demonstrated to be effective in relapsed patients. Based on previous trial results, it is hoped that bortezomib, in replacing vincristine in the VAD standard therapy, can improve the response to treatment of patients with multiple myeloma, with manageable side effects. This is an international, multicentre, randomised, open-label, parallel group study. About 212 patients will take part in the study. Patients will be treated with either bortezomib (PS-341), Adriamycin and Dexamethasone (PAD) or Vincristine, Adriamycin and Dexamethasone (VAD). There will be an initial 14 day screening period to evaluate if the patient is suitable for the study. After screening, eligible patients will be randomised to receive either PAD or VAD. Patients will receive therapy for up to 8 treatment cycles of 28 days each. After the treatment period, there will be a long-term follow-up period with monthly visits until disease progression or relapse. Thereafter follow-up will be continued by at least a phone call every other month. This long-term follow-up period will be performed for all patients until the last patient was treated and followed up for 1 year. Response to treatment will be assessed according to the European group for blood and marrow transplant criteria (EBMT). Disease burden will be monitored by measuring M-protein concentration in serum and in urine every 4 weeks until disease progression or relapse. Thereafter follow-up for survival will be continued every other month by at least a phone call. Safety will be assessed by monitoring of adverse events (AEs), vital signs, physical examination and clinical laboratory tests. Treatment with PAD or VAD will be for up to 8 cycles of 28 days each. Treatment beyond 6 cycles will be discussed on individual basis. Proposed dosages are: bortezomib 1.3 mg/m² intravenous (IV) bolus on Days 1, 4, 8, and 11; vincristine 0.4mg IV push on Days 1 to 4; doxorubicin 9mg/m² IV push on Days 1 to 4; dexamethasone in 1st cycle 40 mg daily on Days 1 to 4, 9 to 12 and 17 to 20, orally (or equivalent parenteral dose) and on subsequent cycles as 40 mg daily on Days 1 to 4 and 17 to 20 only.