Treatment with bortezomib in multiple myeloma is associated with only a transient and brief increase of bone specific alkaline phosphatase.

There are indications of a bone anabolic effect associated with bortezomib treatment. We present a study with long follow up, measuring bone specific alkaline phosphatase (bALP) for a year during and after treatment in an unselected cohort of myeloma patients treated with bortezomib, and assess factors of potential influence on the increase of bALP. Our main findings are that bALP increase is of short duration and declines significantly even during continued treatment with bortezomib. Only myeloma response was associated with a significant increase of bALP; whereas previous treatment with bortezomib, previous or concomitant treatment with zoledronic acid i.v., dose of bortezomib, line of treatment, or combination with other chemotherapy was not.