Pharmaxis Ltd (ASX:PXS), a clinical-stage drug development company, has revealed the results of data analysis from the second of three stages in its phase 1c clinical trial (MF‐101) studying a potential new treatment for the bone marrow cancer myelofibrosis.
The company has found that the increase in the dose of its PXS‐5505 drug led to a predictable increase in drug blood levels in patients and showed the same good tolerability seen in the first dose cohort.
The third dose cohort of the clinical trial is already fully recruited, and dosing of all patients is expected to commence at participating sites in Australian and South Korean hospitals later this week.
“Deliver results by the end of next year”
Pharmaxis CEO Gary Phillips said: “We’re working to apply PXS‐5505 to cancer treatment by inhibiting the LOX and LOXL2 enzymes, which play a significant role.
“The results from these second of three dose cohorts in our myelofibrosis clinical trial show a reassuring dose-related increase in blood drug levels and good tolerability.
“We anticipate that we will also see dose-related increases in levels of LOX and LOXL2 inhibition when that data becomes available later this month.
“We are on track to commence dosing in the six‐month dose-expansion study later this year and deliver results by the end of next year.”
Six-month dose-expansion phase
Pharmaxis will assess the safety and pharmacokinetics of the drugs PXS-5505 following 28 days on the third dose.
This assessment will select the optimal dose to use in the six‐month dose-expansion phase 2a to further evaluate safety and efficacy.
Sites in other countries, including the USA and Taiwan, are currently being engaged in anticipation of the dose-expansion phase commencing recruitment to 24 patients later this year.
Drug has potential in several other cancers
The phase 1c/2a trial MF‐101 cleared by the Food and Drug Administration (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.
An effective pan‐LOX inhibitor for myelofibrosis would open a market that is conservatively estimated at US$1 billion per annum.
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 break down the fibrotic tissue in the tumour and enhance the effects of chemotherapy treatment.