Results after long-term follow-up from the CAN2007 phase I/II study of weekly or twice-weekly bortezomib in patients (pts) with relapsed systemic light-chain (AL) amyloidosis.
8545 Background: Data from multiple studies suggest that bortezomib alone or in combination regimens is active in newly diagnosed and relapsed AL. CAN2007 (NCT00298766) was the first prospective study of single-agent bortezomib in relapsed AL. Here we report outcome data at study closure after a median follow-up of 51.8 mos (median 46.1–66.1 mos). Methods: 70 pts received bortezomib 0.7, 1.0, 1.3, or 1.6 mg/m2 on days 1, 8, 15, and 22 of 35-day cycles (QW) or 0.7, 1.0, or 1.3 mg/m2 on days 1, 4, 8, and 11 of 21-day cycles (BIW) for up to 8 cycles (or longer in pts with evidence of ongoing clinical benefit). The maximum tolerated dose was not reached on either schedule; 18 and 34 pts were treated at the maximum planned doses of 1.6 mg/m2 QW and 1.3 mg/m2BIW, respectively, and 18 pts were treated at lower doses. Post-treatment, pts were followed every 6 weeks until disease progression, and then every 3 mos for survival during the long-term follow-up phase. Results: Pts received a median (range) of 8 (1–39), 6 (1–57), and 8 (3–57) cycles of bortezomib in the 1.6 mg/m2 QW, 1.3 mg/m2 BIW, and lower-dose groups, respectively; overall, 32 (46%) pts received ≥8 cycles, and 4 pts were still on treatment and had received ≥39 cycles at study closure. Hematologic responses and outcomes are summarized below. Median (range) follow-up for survival was 51.8 (1–68), 46.1 (1–61), and 66.1 (2–80) mos, and 7, 12, and 9 pts have died, in the 1.6 mg/m2 QW, 1.3 mg/m2BIW, and lower-dose groups, respectively. Median overall survival (OS) in all 70 pts was 62.7 mos, and 4-yr OS rate was 67.3%; data by dose group are shown below. Conclusions: Single-agent bortezomib produces durable hematologic responses and promising long-term OS data in pts with relapsed AL. Clinical trial information: NCT00298766. [Table: see text]