Bendamustine (Treanda): Alkylating agent approved for the treatment of chronic lymphocytic leukemia

Bendamustine, an alkylating agent, is a bifunctional mechlorethamine derivative. This agent's exact mechanism of action is unknown. Bendamustine was approved on March 20, 2008, for the treatment of chronic lymphocytic leukemia (CLL).

Efficacy. The efficacy of bendamustine was evaluated in an open-label, randomized, controlled, multicenter trial that enrolled 301 treatment-naïve patients with Binet stage B or C (Rai stages I–IV) CLL that required treatment. Patients were randomized to receive intravenous (IV) bendamustine 100 mg/m² via a 30-minute infusion on Days 1 and 2 or oral chlorambucil 0.8 mg/kg on Days 1 and 15 of each 28-day cycle. The efficacy end points were objective response rate (ORR) and progression-free survival (PFS). Patients treated with bendamustine demonstrated an ORR of 59% (95% CI, 51.03%–66.62%) versus 26% (95% CI, 18.64%–32.71%) among patients who received chlorambucil (P<.0001). Median PFS among bendamustine-treated patients was 18 months (95% CI, 11.7–23.5) versus 6 months (95% CI, 5.6–8.6) among patients treated with chlorambucil (HR=0.27; 95% CI, 0.17–0.43; P<.0001).

Safety. Bendamustine treatment is associated with myelosuppression. Infections have been reported in patients treated with bendamustine; some of these infections have been associated with hospitalization, septic shock, or death. Bendamustine-treated patients have experienced infusion reactions. Rarely, severe anaphylactic and anaphylactoid reactions have occurred. Bendamustine therapy has been associated with tumor lysis syndrome. Skin reactions such as rash, toxic skin reactions, and bullous exanthema have been reported in patients treated with bendamustine. The most common adverse events associated with bendamustine treatment include neutropenia, pyrexia, thrombocytopenia, nausea, anemia, leukopenia, and vomiting.