Randomized phase 2 study of obinutuzumab monotherapy in symptomatic, previously untreated chronic lymphocytic leukemia.

Obinutuzumab is a glycoengineered, type 2 anti-CD20 humanized antibody with single-agent activity in relapsed chronic lymphocytic leukemia (CLL). With other CD20 antibodies, a dose-response relationship has been shown. We therefore performed a randomized phase 2 study in symptomatic, untreated CLL patients to evaluate if an obinutuzumab dose response exists. Obinutuzumab was given at a dose of 1000 mg (100 mg IV day 1, 900 mg day 2, 1000 mg day 8 and day 15 of cycle 1; 1000 mg day 1 of cycles 2-8) or 2000 mg (100 mg IV day 1, 900 mg day 2, 1000 mg day 3, 2000 mg day 8 and day 15 of cycle 1; 2000 mg day 1 of cycles 2-8). The primary end point was overall response rate (ORR). Eighty patients were enrolled with similar demographics: median age 67 years, 41% high-risk Rai disease, and 10% del(17p)(13.1). ORR (67% vs 49%, P = .08) and complete response (CR) or CR with incomplete cytopenia response (20% vs 5%) favored 2000 mg obinutuzumab. Overall, therapy was well tolerated, and infusion events were manageable. This study demonstrates significant efficacy of obinutuzumab monotherapy, for 1000 mg as well as for 2000 mg, in untreated CLL patients with acceptable toxicity. Although exploratory, a dose-response relationship may exist, but its relevance to improving progression-free survival is uncertain and will require further follow-up. This trial was registered at www.clinicaltrials.gov as #NCT01414205.

Long-term safety of rituximab in rheumatoid arthritis: 9.5-year follow-up of the global clinical trial programme with a focus on adverse events of interest in RA patients.

OBJECTIVES: Evaluation of long-term safety of rituximab in rheumatoid arthritis (RA). METHODS: Pooled observed case analysis of data from patients with moderate-to-severe, active RA treated with rituximab in a global clinical trial programme. RESULTS: As of September 2010, 3194 patients had received up to 17 rituximab courses over 9.5 years (11 962 patient-years). Of these, 627 had >5 years' follow-up (4418 patient-years). A pooled placebo population (n=818) (placebo+methotrexate (MTX)) was also analysed. Serious adverse event and infection rates generally remained stable over time and multiple courses. The overall serious infection event (SIE) rate was 3.94/100 patient-years (3.26/100 patient-years in patients observed for >5 years) and was comparable with placebo+MTX (3.79/100 patient-years). Serious opportunistic infections were rare. Overall, 22.4% (n=717) of rituximab-treated patients developed low immunoglobulin (Ig)M and 3.5% (n=112) low IgG levels for ≥4 months after ≥1 course. SIE rates were similar before and during/after development of low Ig levels; however, in patients with low IgG, rates were higher than in patients who never developed low IgG. Rates of myocardial infarction and stroke were consistent with rates in the general RA population. No increased risk of malignancy over time was observed. CONCLUSIONS: This analysis demonstrates that rituximab remains generally well tolerated over time and multiple courses, with a safety profile consistent with published data and clinical trial experience. Overall, the findings indicate that there was no evidence of an increased safety risk or increased reporting rates of any types of adverse events with prolonged exposure to rituximab during the 9.5 years of observation.