Phase II study of lenalidomide (Len), bortezomib (Bz), and dexamethasone (Dex) in patients (pts) with relapsed or relapsed and refractory multiple myeloma (MM)

8545 Background: Single-agent Bz and Len/Dex are approved for pts with relapsed MM following ≥1 prior therapy. In a phase I study, Len/Bz (MTD: 15mg/1.0mg/m2) ± Dex 20–40mg achieved a 58% response rate in relapsed/refractory MM pts. This phase ll study evaluated Len/Bz/Dex at the phase-l MTD in up to 65 pts with relapsed/refractory MM, following 1–3 prior lines of therapy. Methods: Pts received Len 15 mg, d 1–14, Bz 1.0 mg/m2, d 1, 4, 8, 11, and Dex 40/20 mg (cycles 1–4/5–8) on days of/after Bz, for up to eight 21d cycles. Based on safety data, Dex dosing was reduced to 20/10 mg. After cycle 8, pts with stable or responding disease received Len (d 1–14)/Bz (d 1, 8) at doses tolerated at end of cycle 8, and Dex 10 mg, d 1, 2, 8, 9. Pts received concomitant antiviral and anti-thrombotic prophylaxis. Response was assessed every 3 weeks according to modified EBMT and Uniform Criteria. Toxicities were assessed using NCI CTCAE v3.0. Pts with G≥ 2 peripheral neuropathy (PN) were excluded. Primary end point was T...