Old cancer drug gets fresh look

Heidi Ledford in Nature:

When Dave deBronkart was diagnosed with advanced kidney cancer in 2007, he learned about a treatment called high-dose interleukin-2 (IL-2) that fires up the body’s immune system to fight the disease. The response rate was not great — tumours shrank in only about 15% of patients. And as many as 4% of people died from the treatment. But some of those who responded survived for years or even decades. DeBronkart’s prognosis was grim — only 8% of people with his disease survive for five years past diagnosis. He says that he was willing to risk what life he might have had left for the possibility of stopping his cancer’s growth: “I said, ‘Lethal side effects? OK.’ ” Now, nearly seven years after his treatment, deBronkart’s immune system continues to hold his cancer in check.

When researchers gather this week for the annual American Society of Clinical Oncology (ASCO) meeting in Chicago, Illinois, the spotlight will be on immunotherapies — a class of drugs that, like IL-2, kindle the immune system’s ability to fend off cancer (see Nature 508, 24–26; 2014). Attendees will hear the latest about a new generation of these drugs — particularly those targeting a protein called PD-1, which cancers use to fend off immune-system attack. Pharmaceutical companies are racing to bring these PD-1 inhibitors to market. Other data to be presented at the meeting suggest that IL-2, the drug that saved deBronkart and the first cancer immunotherapy approved by the US Food and Drug Administration (FDA), may be on the verge of a revival after having fallen out of favour. Two years after he finished the therapy, deBronkart learned that because of IL-2’s risks, three-quarters of eligible patients are never told that it is an option. “There are patients who are dying without ever getting a potentially curative treatment,” says Steven Rosenberg, an oncologist at the US National Cancer Institute in Bethesda, Maryland. “It’s a real problem.”

More here.