Randomized Phase III Study of Pegylated Liposomal Doxorubicin Plus Bortezomib Compared With Bortezomib Alone in Relapsed or Refractory Multiple Myeloma: Combination Therapy Improves Time to Progression

Median time to progression was increased from 6.5 months for bortezomib to 9.3 months with the PLD + bortezomib combination (P = .000004; hazard ratio, 1.82 [monotherapy v combination therapy]; 95% CI, 1.41 to 2.35). The 15-month survival rate for PLD + bortezomib was 76% compared with 65% for bortezomib alone (P = .03). The complete plus partial response rate was 41% for bortezomib and 44% for PLD + bortezomib, a difference that was not statistically significant. Median duration of response was increased from 7.0 to 10.2 months (P = .0008) with PLD + bortezomib. Grade 3/4 adverse events were more frequent in the combination group (80% v 64%), with safety profiles consistent with the known toxicities of the two agents. An increased incidence in the combination group was seen of grade 3/4 neutropenia, thrombocytopenia, asthenia, fatigue, diarrhea, and hand-foot syndrome.

PLD with bortezomib is superior to bortezomib monotherapy for the treatment of patients with relapsed or refractory multiple myeloma. The combination therapy is associated with a higher incidence of grade 3/4 myelosuppression, constitutional symptoms, and GI and dermatologic toxicities.