We investigated the impact of subcutaneous versus intravenous bortezomib in
the MM5 trial of the German-Speaking Myeloma Multicenter Group which compared
bortezomib, doxorubicin, and dexamethasone with bortezomib, cyclophosphamide,
and dexamethasone induction therapy in newly diagnosed multiple myeloma. Based
on data from relapsed myeloma, the route of administration for bortezomib was
changed from intravenous to subcutaneous after 314 of 604 patients had been
enrolled. We analyzed 598 patients who received at least one dose of trial
medication. Adverse events were reported more frequently in patients treated
with intravenous bortezomib (intravenous=65%; subcutaneous=56%, P=0.02). Rates
of grade 2 or more peripheral neuropathy were higher in patients treated with
intravenous bortezomib during the third cycle (intravenous=8%;
subcutaneous=2%, P=0.001). Overall response rates were similar in patients
treated intravenously or subcutaneously. The presence of International Staging
System stage III disease, renal impairment or adverse cytogenetic
abnormalities did not have a negative impact on overall response rates in
either group. To our knowledge this is the largest study to present data
comparing subcutaneous with intravenous bortezomib in newly diagnosed myeloma.
We show better tolerance and similar overall response rates for subcutaneous
compared to intravenous bortezomib. The clinical trial is registered at
eudract.ema.europa.eu as n. 2010-019173-16
