Paclitaxel, topotecan and rituximab: long term outcomes of an effective salvage programme for relapsed or refractory aggressive B-cell non-Hodgkin lymphoma

Relapsed aggressive lymphomas are often treated with platinum-based chemotherapy (PBC) followed by an autologous stem cell transplant (ASCT). Response rates to PBC in patients with relapsed aggressive lymphomas are c. 60%, and non-responders have a dismal prognosis. Novel therapies for aggressive lymphomas, including those failing PBC, are needed. We performed a phase II study of paclitaxel, topotecan and rituximab (TTR) in patients with relapsed or refractory diffuse large B-cell, follicular grade IIIB, or transformed lymphomas, including those who previously failed PBC. The median age of the 72 patients enrolled was 54 years. Responding patients were offered ASCT after two courses. The overall response rate was 69% for all patients (n = 49/71) and 45% for those who previously failed PBC (n = 9/20). With a median follow up of 125 months for the censored observations, the overall survival (OS) and progression-free survival at 5 years was 39% and 27%, respectively. Responding patients who received ASCT had an OS of 63% at 5 years. Our results demonstrate that TTR is an effective salvage regimen for patients with relapsed aggressive B-cell lymphomas, including those who previously failed PBC. Given the declining therapeutic outcomes of salvage PBC in the rituximab era, further evaluation of TTR is warranted.

Crystallization and preliminary X-ray diffraction analysis of suramin, a highly charged polysulfonated napthylurea, complexed with a myotoxic PLA2 from Bothrops asper venom

Suramin is a highly charged polysulfonated napthylurea that interferes in a number of physiologically relevant processes such as myotoxicity, blood coagulation and several kinds of cancers. This synthetic compound was complexed with a myotoxic Lys49 PLA(2) from Bothrops asper venom and crystallized by the hanging-drop vapor diffusion method at 18 degrees C. The crystals belong to the orthorhombic space group P2(1)2(1)2(1), with unit cell parameters a=49.05, b=63.84 and c=85.67 angstroms. Diffraction data was collected to 1.78 angstroms.

Toxicity, efficacy, and pharmacology of suramin in adults with recurrent high-grade gliomas

PURPOSE

To determine the toxicity, efficacy, and pharmacology of suramin in patients with recurrent or progressive recurrent high-grade gliomas.

PATIENTS AND METHODS

Fifty adults were to receive suramin. However, if no responses were seen in the first ten patients, the study was to be terminated. A total of 12 patients were enrolled onto this trial. Ten patients had glioblastoma multiforme, and 11 had received prior nitrosoureas.

RESULTS

Drug-related toxicities were modest and reversible. Three patients developed grade 3 to 4 neutropenia, constipation, diarrhea, or nausea. No CNS bleeding was observed. Median time to progression was 55 days (range, 17 to 242 days) and median survival was 191 days (range, 42 to 811 days). No partial or complete responses were seen at 12 weeks. However, the clinical outcome of three patients suggests that evidence of suramin activity may be delayed. One patient who "progressed" after 12 weeks of suramin had a subsequent marked reduction in tumor size and has maintained an excellent partial response for over 2 years without other therapy. Two others had disease stabilization and lived for 16 and 27 months. Pharmacokinetics from 11 patients revealed that all reached target suramin concentrations.

CONCLUSION

This study demonstrates that suramin is well tolerated by patients with recurrent high-grade gliomas and may have efficacy in this disease. Its pharmacology seems unaffected by anticonvulsants. As a result of this data, suramin and radiation are now being administered concurrently to patients with newly diagnosed glioblastoma multiforme, with survival as the primary outcome.