Lintuzumab is a humanized monoclonal antibody that targets the CD33 antigen, which is expressed on a number of hematologic malignancies, including AML, myelodysplastic syndromes (MDS) and several myeloproliferative disorders. Seattle Genetics recently reported data from a completed phase Ia dose-escalation clinical trial of lintuzumab demonstrating multiple complete responses at well-tolerated doses. In addition to the phase IIb clinical trial, the company is also conducting a phase Ib trial of single-agent lintuzumab in patients with AML or MDS and a phase I trial of lintuzumab in combination with Revlimid(R) (lenalidomide) for advanced MDS.
The Independent Data Monitoring Committee (IDMC) has now completed a pre-specified safety review of data from the ongoing phase IIb trial of lintuzumab (SGN-33) in combination with low-dose cytarabine chemotherapy for older patients with acute myeloid leukemia (AML).
After review of the collected data, the IDMC did not identify any safety concerns and has recommended that the trial continue per the protocol. This interim assessment was based upon a planned evaluation of safety data from the first 50 percent of patients randomized in the study who received at least one dose of treatment. The company has completed approximately two-thirds of the total target enrollment of 210 patients, and expects to report data in the first half of 2010.
Another drug from the same company, SGN-40 (dacetuzumab), is being tested b-cell lymphomas (PDF of poster) and multiple myeloma and was snapped up early by Genentech in a licensing deal in 2007. Seattle Genetics also has a monoclonal antibody in development for autoimmune diseases (SGN-70 and SGN-75), which target CD70. The latter is in preclinical development at present.
It should be an interesting company to watch out for.