A new immunotherapy drug has produced striking early results in men with advanced prostate cancer.
Researchers reported that the treatment shrank tumours in several patients.
The therapy, called VIR-5500, directs the body’s killer T-cells toward cancer cells.
It activates mainly inside tumours, which helps limit harmful side effects.
Most participants experienced only mild reactions during the trial.
Fifty-eight men joined the phase one study after other treatments stopped working.
At the highest dose, many showed major drops in prostate-specific antigen levels.
Some patients recorded reductions of more than ninety percent.
Doctors also observed measurable tumour shrinkage in nearly half of the evaluated cases.
One patient saw multiple liver lesions disappear after repeated treatment cycles.
Researchers described the findings as unprecedented for prostate cancer.
The disease has long resisted immunotherapy because of its weak immune response.
Specialists welcomed the results but called for larger and more diverse trials.
They want to confirm long-term safety, effectiveness, and survival benefits.
Prostate cancer affects about 1.5 million men each year worldwide.
Experts say new treatments remain urgently needed for advanced stages.
Further studies will now test whether the drug can extend lives and move toward potential cures.
