For more than a century, scientists have been attempting to harness the immune system to fight cancer — trying to get the antibodies and cells that protect us from viruses and bacteria to kill diseased cells. Every once in a while, a tantalizing success occurred but could not be duplicated.

This time, the success was repeated in multiple advanced melanoma patients.

Researchers believe the same approach could work for kidney, lung and other cancers.

Already the researchers are planning a nationwide clinical trial to determine if the findings can allow the drug to help many more patients with advanced melanoma.

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