An experimental treatment called VIR-5500 has produced striking results in early trials.
Researchers reported tumour shrinkage in men with advanced prostate cancer.
Prostate cancer affects about 1.5 million men worldwide each year.
Many advanced cases eventually stop responding to standard therapies.
VIR-5500 uses immunotherapy to direct the body’s T-cells toward cancer.
The engineered antibody activates mainly inside the tumour.
This design reduces inflammation and may allow fewer treatment doses.
Scientists tested the drug in 58 men with treatment-resistant disease.
Most participants experienced only mild side effects.
Eighty-eight percent reported low toxicity.
Researchers measured prostate-specific antigen levels to track response.
Among patients receiving the highest dose, most showed major declines.
Fourteen of seventeen saw PSA fall by at least half.
Nine recorded drops of ninety percent or more.
Five reached reductions close to complete suppression.
Tumour scans also showed encouraging changes.
Five of eleven men had measurable tumour shrinkage.
One patient with liver spread saw multiple lesions disappear after treatment.
Experts called the findings unprecedented for an “immune-cold” cancer.
They stressed the results still require larger, peer-reviewed studies.
Scientists are planning further trials to confirm safety and long-term benefit.
Researchers also want broader patient groups to ensure equal effectiveness.
Cancer specialists say the approach could open a new treatment class.
They hope it will extend survival and improve quality of life for patients.
