Results of a Phase IIb study, presented at the American Association for Cancer Research 101st Annual Meeting 2010, showed a clear clinical benefit from trabedersen, a TGF-beta inhibitor, in patients with high-grade glioma; the Phase III study SAPPHIRE (NCT00761280) is currently enrolling.

"Current therapies for this patient population include surgery, radiation and chemotherapy with temozolomide," said Dr. Piotr Jachimczak, senior scientific advisor at Antisense Pharma. "Trabedersen performed better than these therapy standards on all levels in anaplastic astrocytoma."

Antisense Pharma is developing trabedersen, a TGF-beta-2 specific phosphorothioate antisense oligonucleotide administered intratumorally using convection-enhanced delivery. The company is funding its own research through a venture capital conglomerate.

Researchers enrolled 145 patients with recurrent or refractory high-grade glioma. These patients were randomly assigned to receive either trabedersen at 10 microM or 80 microM or standard chemotherapy.

Results showed that the lower dose of trabedersen performed most optimally in anaplastic astrocytoma. At 24 months, 83.3 percent had survived compared with 53.3 percent on the higher dose and 41.7 percent on standard chemotherapy. Duration of response was 29.1 months compared to the standard chemotherapy group of eight months and the median overall survival benefit of 10 microM trabedersen over chemotherapy was 17.4 months.

"This is clearly a novel therapeutic option for patients with this disease," said Jachimczak.

In young patients suffering from glioblastoma (WHO Grade 4), specifically those younger than 55 years, the two-year survival rate was 44 percent, compared with 13.3 percent with standard chemotherapy.

Source: The American Association for Cancer Research