It means the biotech now has patent protection for VAL201 in Japan, Europe and Australia, with further patents pending for the candidate in significant markets across the rest of the world.
The compound is currently in a "Phase I/II dose escalation study to assess safety and tolerability" for treating prostate cancer and other solid tumours.
So far results have been positive and VAL201 has met and exceeded predicted safety and tolerability criteria and most of the patients who have completed the study showed stable disease on imaging following treatment.
Dr Satu Vainikka, ValiRx's chief executive, said: "This latest patent strengthens our worldwide protection for VAL201 and the grant builds pleasingly on the back of VAL201's recent clinical trial success.
"This grant supports the potential value of the compound and solidifies our opportunity in ongoing discussions with potential partners."
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