PharmAust (ASX: PAA) has completed assessment of the first five dogs in a phase IIb trial of its anti-cancer drug monepantel on treatment-naïve B cell lymphoma in canines, revealing only minimal side effects.
The biotech company started the trial in January on six dogs with stage four or five B cell lymphoma across five participating trial sites. One of the dogs was withdrawn from the trial due to non-compliance with dosing instructions (monepantel to be administered after a meal).
A further six pet dogs that were not eligible for the trial are also treated with monepantel under compassionate use in varying combinations with other anti-cancer drugs.
Of the five dogs that completed the trial to date, PharmAust reported a “mild and occasional” lack of appetite in some dogs but said it appears “insiginificant” and difficult to attribute solely to monepantel.
“Pleasingly, side-effect levels to date are below those of other conventional anti-cancer drugs and trial veterinarians report that, at day 28, all participating dogs have been in good spirits and well within themselves,” the company stated in Tuesday’s announcement.
“As such the owners have elected to continue treating their dogs with monepantel on compassionate use, post-trial.”
PharmAust chief scientific officer Dr Richard Mollard said it was “very satisfying” to see minimal side effects after the observed inappetence during the first trial with the tablets.
“This gives PharmAust plenty of room to further monepantel testing as a standalone therapy or in combination with other drugs in future larger trials,” he added.
PharmAust said it will next perform an interim analysis of the monepantel and monepantel sulfone blood levels being achieved in this study.
Determination of these levels will provide a conservative baseline threshold for the very satisfactory side effect profile observed. The levels will also provide invaluable information for establishing future standalone and/or combination treatment regimens for phase III trials in dogs.
In addition, the pharmacokinetic data extracted is expected to provide important data for forthcoming trials in humans.
The phase IIb trial is still recruiting and progressing.
The principal investigator is evaluating results and the release of further trial data will be announced when clear and meaningful outcomes arise.