The strategy may still produce some wins.

"There is plenty of opportunity for serendipity now," says Robert Vonderheide, who studies CD40 at the University of Pennsylvania in Philadelphia.

But as the field matures, he says, this could give way to a more-systematic approach, similar to the careful planning and testing of variables used for pediatric leukemias.


Despite his concerns, Garon is excited to be a part of the immunotherapy wave.


Last autumn, he and his colleagues held a banquet for the patients who had been enrolled in his first immunotherapy trials three years earlier. These were the lucky survivors - the few who had shown a dramatic response.


As he looked around the table at the guests of honor, he marveled at their recovery. All had been diagnosed with advanced lung cancer, and many had been too weak to work.


Now they were talking about their families, re-embarking on careers and taking up old hobbies such as golf and running.

"We've never been able to hold a banquet like that before," he says. "I would love to hold many more."