Masitinib in Relapse or Refractory Multiple Myeloma With t(4/14) Translocation Expressing or Not FGFR3

Inclusion Criteria: * Confirmed multiple myeloma with a t (4; 14) translocation by FISH and PCR, expressing or not expressing FGFR3 identified by FACS * Patients with Multiple Myeloma progressing or relapsing after at least two prior therapies (including conventional chemotherapy and/or high dose therapy) or who get a reduction of M-protein less than 75% within 3 months after a high dose treatment (Melphalan 200mg/m2) or after the plateau obtained for 3 months duration following to a conventional chemotherapy * Patient with rapidly progressive disease with cytopenia and / or renal failure have to be stabilized with chemotherapy (if possible 3 cycles of VTD ( Bortezomib/Thalidomide/dexamethasone) or high dose Melphalan regimen followed by a 4 weeks washout period before the inclusion in the study. * Patients must have a clearly detectable and quantifiable monoclonal M- component value (\>5 g/l) in the serum and / or urine light chain excretion (\>0,5 g/d) Exclusion Criteria: * Prior corticosteroids within two weeks before enrolment * Prior local irradiation within two weeks before enrolment * Prior experimental or standard treatment (other than steroids and local irradiation) within 30 days before enrolment