Cortice Biosciences reports initial results from a Phase I/II trial of TPI 287 to treat recurrent Glioblastoma

These results will be presented in a poster presentation this evening at 7:30 PM ET at the 19th Annual Scientific Meeting and Education Day of the Society for Neuro-Oncology in Miami Beach, FL.

TPI 287 is a novel microtubule stabilizing agent that readily penetrates the blood-brain barrier. Prior preclinical and clinical results support the potential of this agent for treatment of cancers of the brain, including GBM, a highly aggressive malignancy with few therapeutic options.

Cortice is running two multi-center clinical trials designed to determine the maximum tolerated dose and efficacy of TPI 287 in combination with standard-of-care bevacizumab for treatment of recurrent GBM that either has not been or has been previously treated with bevacizumab.

The goal of both trials is to determine the maximum tolerated dose (MTD) of TPI 287 in these treatment settings as well as objective response, progression free survival, and overall survival.

Results from the on-going dose-escalation stage of the CB-017 study, which is enrolling recurrent GBM patients who have not been previously treated with bevacizumab, will be presented this evening. To date, the 15 patients enrolled have received one or more doses of TPI 287 at concentrations ranging from 140 to 180 mg/m2 administered intravenously every three weeks in combination with bevacizumab (10 mg/kg every two weeks). Responses were evaluated per RANO criteria by the site investigators.

Six patients continue to be treated on study.

At the time of presentation, 13 patients were evaluable for efficacy at doses up to 170 mg/m2 of TPI 287:

• Seven patients achieved objective responses, including 5 confirmed (1 complete response; 4 partial responses) and 2 unconfirmed (1 complete response; 1 partial response)
• The 5 confirmed responses were or have been durable 5.5 to 8.3 months; three remain on-going
• Five patients achieved stable disease
• Only 1 patient had progressive disease at first assessment for response

Safety data was available from 12 patients treated at doses up to 170 mg/m2 of TPI 287. With the exception of Grade 3 myelosuppression (2 patients), all adverse events regarded as possibly related to TPI 287 have been mild-to-moderate. No dose limiting toxicities have been observed to date.

"TPI 287 is a potent cytotoxic drug able to penetrate the brain at therapeutic concentrations. The results presented today support the safety and efficacy of this agent in glioblastoma," said Dr. Samuel Goldlust, Medical Director of the Brain and Spine Institute of the John Theurer Cancer Center and Principal Investigator of CB-017.

"It is particularly promising to see frequent durable responses at doses of TPI 287 below the MTD. These results support the likelihood of bringing a much needed novel therapy to patients with few options at time of recurrence."

Given that the MTD has not been reached, dose escalation with TPI 287 continues in the 180 mg/m2 treatment cohort. Cortice plans to provide further updates to CB-017, as well as preliminary results from CB-018, a Phase 2 trial evaluating TPI 287 in patients with prior bevacizumab treatment experience, at future medical meetings in 2015.

"The overall response rate of 54% achieved with the TPI 287 plus bevacizumab combination at this early stage of CB-017 is highly encouraging, especially in the context of the 24% response rate observed in the monotherapy cohorts of the Avastin registration studies for GBM," said George Farmer, Ph.D., Chief Executive Officer of Cortice.

"Moreover, the results from CB-017 include two complete responses, outcomes rarely observed in this population. We look forward to additional follow up from this study and CB-018, which will help us understand the potential of TPI 287 in this devastating disease."

TPI 287 is a novel taxoid which binds to and stabilizes the assembly of microtubules similarly to commonly used taxanes, including paclitaxel (Taxol(R) and Abraxane(R)) and docetaxel (Taxotere(R)). In oncology treatment settings, microtubule stabilization by these agents leads to mitotic arrest and cancer cell death.

TPI 287 has advantages over the taxanes due to its ability to circumvent common drug resistance mechanisms and its propensity to penetrate the central nervous system. Accordingly, TPI 287 has the potential to treat primary brain tumors and secondary brain metastases that are often shielded from systemic administration of taxanes.

Microtubule stabilization by TPI 287 may also have potential for the treatment of neurologic disorders affected by tau protein pathology. These include tauopathies such as Alzheimer’s disease and orphan diseases, such as progressive supranuclear palsy, corticobasal degeneration, and frontotemporal dementia.