• Phase 1b dose escalation stage of the Phase 1b/2 Zantrene study in AML has completed using a 4-day treatment of Zantrene in combination with fludarabine and clofarabine
• Encouraging clinical responses were observed in this very heavily pre-treated AML patient population with 3 of the 6 patients bridged to a stem cell transplant
• The study led by Professor Arnon Nagler of the Chaim Sheba Medical Center, Israel will now advance to the Phase 2 efficacy stage recruiting up to 17 patients.

Race Oncology Limited (“Race”) is pleased to announce the dose escalation Phase 1b stage of the relapsed or refractory Acute Myeloid Leukaemia (R/R AML) trial running at the Chaim Sheba Medical Centre, Israel has successfully completed after the treatment of the first six patients.
The six patients were heavily pre-treated and had received a median of four prior lines of AML treatment (range 2-8).

By design, the primary endpoint of the initial phase of this 2-stage clinical trial is establishing the recommended dose to be used in the subsequent Phase 2 expansion (efficacy) stage. This first stage requires identifying the treatment dose level that achieves two or fewer dose-limiting toxicities (DLTs) from six consecutively treated patients. In the initial six patients treated, two DLTs were reported (one Grade 3 elevated liver enzymes and one Grade 5 infection). Both DLTs occurred in the most heavily pre-treated patients who had received five and eight prior lines of treatment, respectively.

“The positive results from the first stage of this trial in such a heavily pre-treated relapsed or refractory Acute Myeloid Leukaemia population is encouraging, especially with three of the patients being subsequently bridged to transplant. We look forward to the next stage of this study which, together with data from the EMD AML Trial (RAC-006) which is soon to commence recruitment in Australia, is extending our understanding of Zantrene in a modern AML setting.”

Race CMO Dr David Fuller

Efficacy results in this refractory patient population were very encouraging, with one patient showing a complete response (CR) based on morphology, two patients having a partial response (PR) including one with extramedullary disease, two showing no response (NR), and one patient not assessable (NA) due to death from infection. Infection is a known side effect of all intensive chemotherapeutic regimens and is one of the leading causes of death in AML patients.

“The encouraging results of our Phase I study with Zantrene monotherapy and moreover the current Phase II study altogether with Zantrene in combination in extremely heavily treated advanced high risk AML patients are encouraging and may indicate a role for Zantrene in modern AML treatment paradigm to the benefit of our patients.”

Study Lead Prof Arnon Nagler

Three patients (1 CR and 2 PR) were bridged to an allogeneic stem cell transplant. Bridging a patient to transplant is an important positive outcome in AML treatment as it offers the patient the potential of long-term remission. Of note, these three patients had all received less than five prior lines of treatment. Poor or no response to known efficacious treatments is common and expected in heavily pre-treated cancer patients.

“We are very excited about the positive data from the first stage of this trial in such a heavily pre-treated R/R AML population, and we now look forward to the next phase, where we expect to see more patients respond favourably and with a consistently tolerable side effect profile. It appears that bridging to transplantation with long-term disease control can be achieved with confidence, given we can since perceive that the side effects reverse within a few weeks of the course being completed.”

Race Clinical Advisory Board Chair Prof Borje Andersson

The trial will now progress to the Phase 2 efficacy (expansion) stage using a 4-day schedule of Zantrene® (bisantrene dihydrochloride) in combination with fludarabine and clofarabine.