The purpose of this study is to evaluate the efficacy and safety of a consolidation therapy with bortezomib in patients with multiple myeloma aged 61 to 75.

No data supporting the use of bortezomib as a consolidation therapy in multiple myeloma patients are available. Ínterferon tested as consolidation / maintenance therapy has not uniformly proven to prolong survival. In this study the hypothesis is being tested that bortezomib is able to increase duration of response and thus improving survival. This hypothesis is based on the results of the approval study where bortezomib has been tested to improve these endpoints.This is a multicenter, open-label, randomized (patients are assigned to different treatment group by chance) phase III study to evaluate the efficacy and safety of a consolidation therapy with bortezomib in patients with multiple myeloma aged 61 to 75. Three months after receiving high dose melphalan with autologous stem cell transplantation patients will be randomized to receive either consolidation therapy with bortezomib or to be monitored without consolidation therapy. Subjects in the consolidation group will be treated up to 4 cycles (6 weeks each). The main study phase has a duration of 24 weeks. The trial ends after the last enrolled patient has completed a follow-up period of 30 months. The primary objective is to determine the event free survival in treatment and observation group. The secondary objectives are to assess the response rate, overall survival, duration of response, time to progression, short- and long-term toxicities, quality of life and cytogenetic analyses with regard to treatment response, event free survival and overall survival. Primary efficacy analysis: Event free survival is defined as the time from the first disease-related therapeutic procedure until death, progress or relapse. Secondary efficacy analyses: response rate of the treatment group (measured by the relative change of M-protein levels in serum or urine); overall survival is defined as the time from the first therapeutic procedure until death; time to progression is defined as the duration from the date of enrolment until the date of first documented evidence of progressive disease or relapse; duration of response is defined as the duration in months from the date of first evidence of confirmed response to the date of first documented evidence of progressive disease or relapse; quality of life is assessed by the questionnaires EORTC QLQ-C30 (Quality of life questionnaire) and EORTC EQ-5D (Euro Quality of life). Consolidation therapy lasts 4 cycles. Subjects will be treated with bortezomib 1.6 mg/m2 body surface intravenously once weekly for 4 weeks (Days 1, 8, 15, and 22) followed by a 13-day rest period (days 23 to 35). At least 72 hours should relapse between consecutive doses of bortezomib. Therapy should be withheld at the onset of any Grade 3 nonhematological or Grade 4 hematological toxicities excluding neuropathy.

Inclusion Criteria:

• Patients who have had pretreatment with single or tandem high dose melphalan therapy and autologous stem cell transplantation as first line therapy
• at least stable disease after stem cell transplantation
• adequate hematological, hepatic and renal lab parameters
• karnofsky status of 70 or more

Exclusion Criteria:

• non-secretory multiple myeloma
• previous treatment with bortezomib
• allogenic stem cell transplantation
• other co-existing malignancy beside basaliome
• peripheral neuropathy
• epilepsia
• other severe comorbidities (renal, hepatic, cardiovascular, metabolic, infectious etc.)
• history of allergic reactions to bortezomib or mannitol
• expected life expectancy of less than 3 months