Anti-CCR4 antibody demonstrated efficacy, safety in ATL

Ishida T. J Clin Oncol. 2012;doi:10.1200/JCO.2011.37.3472.

Half of patients with adult T-cell leukemia-lymphoma in a recent study responded to KW-0761, a humanized anti-CC chemokine receptor-4 monoclonal antibody.

Few alternative treatment options are available for adult T-cell leukemia-lymphoma (ATL), which usually is resistant to conventional chemotherapies, according to researchers from several sites in Japan.

The current multicenter, phase 2 study evaluates KW-0761 as a treatment for patients with relapsed ATL. CC chemokine receptor-4 (CCR4) is expressed on tumor cells from most patients with this disease.

Study outcomes included efficacy, pharmacokinetic profile and safety, with overall response rate serving as the primary endpoint. Secondary endpoints included PFS and OS from the first dose of the study drug.

Participants were administered 1 mg/kg IV KW-0761 once a week for 8 weeks.

There were 28 patients enrolled, of whom 27 received at least one infusion of the drug.

Thirteen of 26 evaluable patients demonstrated objective responses, for an overall response rate of 50% (95% CI, 30-70). There were eight complete responses.

Median PFS was 5.2 months, and median OS was 13.7 months.

After the eighth infusion, a median half-life period of 422 ± 147 hours was observed.

The infusion reaction rate was 89% and skin rashes occurred in 63% of patients. These were the most common adverse events, and all were manageable and reversible.

“Further investigation of KW-0761 for treatment of ATL and other T-cell neoplasms is warranted,” the researchers wrote.

Harry S. Jacob

Since these data come from a country with high prevalence of HTLV-associated T-cell leukemia-lymphoma, one wonders whether T-cell lymphoproliferative diseases in other geographic sites will be responsive to this therapy.

– Harry S. Jacob, MD, FRCPath(Hon)

HemOnc Today Chief Medical Editor

Disclosure: Dr. Jacob reports no relevant financial disclosures.