ORLANDOAdding rituximab(Drug information on rituximab) (Rituxan) to paclitaxel(Drug information on paclitaxel) (Taxol)/topotecan (Hycamtin) salvage therapy raises response rates by about 25%, more than triples complete response rates, and is effective in both primary refractory and relapsed aggressive B-cell lymphomas.
Phase II Study
Anas Younes, MD, and colleagues from M. D. Anderson Cancer Center reported data from a 45-patient phase II study of the paclitaxel/topotecan/rituximab regimen in a poster presentation at the 43rd Annual Meeting of the American Society of Hematology (ASH abstract 1456).
"We concluded that rituximab improves the response rate of paclitaxel/topotecan and increases the proportion of complete remissions. There was not a significantly different toxicity profile with the addition of rituximab. However, this is not frontline treatment yet," Dr. Younes told ONI in an interview.
The study enrolled 45 patients with relapsed or refractory aggressive non-Hodgkin’s lymphoma (NHL) and included 34 with diffuse large cell, 4 with follicular large cell, and 7 with transformed disease. Twenty patients (44%) had primary refractory disease, and 25 (56%) had relapsed after responding to previous therapy. Most patients had received only a single previous regimen, and 15 (33%) had received prior cytarabine(Drug information on cytarabine)/platinum. The median age was 58.
The regimen included paclitaxel 200 mg/m²IV given over 3 hours on day 1, topotecan 1 mg/m² IV given each day on days 1 to 5, and rituximab 375 mg/m² given 1 day before each paclitaxel/topotecan course. All patients also received prophylactic filgrastim(Drug information on filgrastim) (G-CSF, Neupogen). Courses were repeated every 3 weeks, and patients received a median of three courses.
In patients with primary refractory disease, adding rituximab to the regimen increased the response rate to 55% from the 31% Dr. Younes had reported in a previous study of paclitaxel/topotecan in a similar group of patients.