SuperGen: pentostatin, cyclophosphamide, rituximab together shown to fight leukemia

By Ted A. Knutson

Washington, March 14 - SuperGen, Inc. said Tuesday an article showing pentostatin, cyclophosphamide and rituximab is an active, well-tolerated Regimen for patients with previously treated chronic lymphocytic leukemia appears in the April issue of the Journal of Clinical Oncology.

Mark A. Weiss and colleagues at the Cleveland Clinic and Memorial Sloan Kettering Cancer Center demonstrated higher response rates and similar or less toxicity using a three-drug combination therapy of pentostatin, cyclophosphamide and rituximab (PCR) for previously treated patients with chronic lymphocytic leukemia (CLL) or other low-grade B-cell neoplasms.

The abstract updates a previously reported study on the use of pentostatin and cyclophosphamide in 23 patients with relapsed or refractory CLL.

The two-drug combination therapy was active and well-tolerated. The study achieved an overall response rate of 74%, including 4 complete responses (17%). In these responders, 41% achieved their best response with of pentostatin and cyclophosphamide versus any prior therapy.

Encouraged by those results, the researchers undertook the recent study to investigate how the addition of rituximab to the combination therapy would affect the incidence of response, and to characterize the toxicity of the three-drug regimen with PCR in patients with previously treated B-cell CLL or other low-grade B-cell eoplasms.

A total of 46 patients with either previously treated CLL (32 patients) or other low-grade B-cell neoplasms (14 patients) were treated. The median age was 62 years, with two prior regimens.

Patients received pentostatin 4 mg/m2, cyclophosphamide 600 mg/m2, and rituximab 375 mg/m2.

All drugs were administered on the same day (rituximab omitted from cycle 1), and patients received six cycles at three-week intervals. Filgrastim, sulfamethoxazole/ trimethoprim, and acyclovir were administered prophylactically.

The addition of rituximab improved response duration, survival and overall toxicity. These studies were done sequentially and are not randomized comparisons. The median survival rate for the 32 CLL three-drug combination therapy patients was 44 months versus 17 months for patients on the two-drug combination therapy of pentostatin and cyclophosphamide.

The use of pentostatin in a combination regimen of pentostatin, cyclophosphamide and rituximab appears to be better tolerated than fludarabine, cyclophosphamide and rituximab (FCR).

Comparing this study to results from a similar study using FCR, results included 9% infusion-related toxicity in the PCR group versus 63% with FCR, and infectious complications (including fever of unknown origin) were 28% in PCR patients versus 47% in the FCR group.

SuperGen is a Dublin, Calif.-based pharmaceutical company dedicated to the acquisition, rapid development and commercialization of therapies for solid tumors, hematological malignancies and blood disorders.

© 2015 Prospect News.
All content on this website is protected by copyright law in the U.S. and elsewhere. For the use of the person downloading only.
Redistribution and copying are prohibited by law without written permission in advance from Prospect News.
Redistribution or copying includes e-mailing, printing multiple copies or any other form of reproduction.