Study of Recombinant Human Endostatin Combined with Temozolomide and Irinotecan in Recurrent Gliomas

Almost all gliomas relapse. After temozolomide rechallenge or combination with irinotecan, the progression-free survival rate at 6 months (PFS-6%) of recurrent glioblastoma was about 21%. After treatment with irinotecan-based chemotherapy regimen, the PFS-6% of recurrent lower-grade gliomas was 40%. The optimal chemotherapeutics of recurrent gliomas has yet to be determined. Anti-angiogenesis is a promising therapeutic strategy. Vascular endothelial growth factor-A (VEGF) is the primary driver of angiogenesis in tumors. Bevacizumab, a humanized monoclonal antibody directed against VEGF, is the prototypical anti-angiogenic drug and received accelerated approval of the United States Food and Drug Administration (FDA) for the treatment of recurrent glioblastoma. Bevacizumab inproved the PFS-6% (36%), but had no effect on the overall survival (OS) (9.2 months). Moreover, the effects of bevacizumab are transient and most patients' tumors progress just after a median time of 3-5 months. Recombinant human endostatin (rh-ES) is an endogenous broad-spectrum angiogenesis inhibitor that has been shown to significantly improve therapeutic efficacy when combining with conventional chemotherapy agents in non-small-cell lung cancer, breast cancer and melanoma. In our previous study, we retrospectively analyzed the effect and toxicity of rh-ES when combined with temozolomide and irinotecan on adult recurrent disseminated glioblastoma. After combined treatment, PFS-6% was 23.3%; the median PFS and OS were 3.2 and 6.9 months, respectively, which were promising compared with that in other studies. Once patients get radiographic remission in a short time (4 months), they may get a long PFS.The combined regimen did not reduce the sensitivity of tumor to bevacizumab. After tumor progression from the combined chemotherapy, bevacizumab usage could help to prolong the survival time (5.1 months versus 2.4 months). Moreover, the toxicities of the combination therapy in this study were manageable. On the basis of prior clinical experience, we carry out this prospective trial to confirm the efficacy and safety of the combination of rh-ES, temozolomide and irinotecan in patients with recurrent gliomas.