Pharmaxis Announces Progression of Clinical Trial in Bone Marrow Cancer

PXS-5505 MULTINATIONAL TRIAL IN MYELOFIBROSIS CLEARED BY SAFETY COMMITTEE TO ADVANCE TO SECOND STAGE OF DOSE ESCALATION STUDY

Clinical stage drug development company Pharmaxis Ltd (ASX: PXS) today announced it has completed dosing the first of three stages in its phase 1c clinical trial (MF‐101) studying a potential new treatment for the bone marrow cancer myelofibrosis. The study’s safety monitoring committee that advises on the study progress, has given the green light to progress to the second dose level after reviewing factors including the safety and pharmacokinetic properties of PXS‐5505 in myelofibrosis patients.

Participating Australian and South Korean hospitals will shortly commence dosing of the second dose level for a treatment period of 28 days. The dose escalation phase of the study will inform the selection of the optimum dose of PXS‐5505 to be used in the six‐month dose expansion phase (24 patients) to evaluate safety and efficacy. Sites in other countries including the USA are currently being approached in anticipation of the dose expansion phase commencing recruitment later this year.

Pharmaxis CEO Gary Phillips said, “PXS‐5505 has demonstrated good tolerability and very consistent pharmacokinetic properties in the first dose escalation stage of MF‐101. This is very much in line with the results from our phase 1 healthy volunteer study reported last year. Further data from this first dose will be available in coming weeks but based on the pharmacokinetic profile I anticipate that we will see significant inhibition of all lysyl oxidase enzymes even at this lowest level of dose. We look forward to seeing the data from the next two dose cohorts in 2H 2021 and delivering safety and efficacy data from the 6‐month dose expansion study by the end of next year.”

PXS‐5505 is an orally taken drug that inhibits the lysyl oxidase family of enzymes. In pre‐clinical models of myelofibrosis PXS‐5505 reversed the bone marrow fibrosis that drives morbidity and mortality in myelofibrosis and reduced many of the abnormalities associated with this disease. It has already received IND approval and Orphan Drug Designation for the treatment of myelofibrosis from the FDA.

The phase 1c/2a trial cleared by the FDA under the Investigational New Drug (IND) scheme aims to demonstrate that PXS‐5505, the lead asset in Pharmaxis’ drug discovery pipeline, is safe and effective as a monotherapy in myelofibrosis patients who are intolerant, unresponsive or ineligible for treatment with approved JAK inhibitor drugs.

While Pharmaxis’ primary focus is the development of PXS‐5505 for myelofibrosis, the drug also has potential in several other cancers including liver and pancreatic cancer where it aims to breakdown the fibrotic tissue in the tumour and enhance the effect of chemotherapy treatment.