Cancer patients ignore breakthrough drugs

Only a fraction of patients with hard-to-treat lymphoma ever try two breakthrough "smart-bomb" drugs that bring radiation straight to cancerous cells - with just two shots a week apart, not the usual months of care.

The marketing failure has a manufacturer trying to sell off one of the drugs, and increasingly frustrated specialists worry it will jeopardize attempts to expand this promising new field to fight other cancers, too.

It's called radioimmunotherapy, harnessing homing device-like immune cells - antibodies - with a radioactive drug. The antibodies zero in on cancer and drop their payload, without as much damage to surrounding healthy tissue as chemotherapy can cause.

Only two such drugs are sold today, the lymphoma fighters Zevalin and Bexxar. But more than half a dozen early stage studies of others - against some particularly deadly malignancies, including pancreatic cancer, brain cancers, and advanced prostate cancer - are under way.

The issue: Despite research showing they work well, fewer than 10 percent of lymphoma patients who are candidates for Zevalin and Bexxar ever use them, says Dr. Mark Kaminski of the University of Michigan, a hematologist who co-invented Bexxar.

Why? Specialists cite a complex list of reasons, including that most oncologists aren't licensed to administer the radioactive infusion and must send their patients to a nuclear-medicine doctor.

There's also confusion about the risks of radiation, which studies suggest are minimal, and when the drugs work best - early, not as a last-ditch therapy.

"There's lots of reasons to use them, and seems to be an inertia against them," says Dr. Mitchell Smith, lymphoma chief at Fox Chase Cancer Center in Philadelphia. "I do see it as unfortunate."

Indeed, sales are so weak that Zevalin maker Biogen Idec announced in December it was hunting a buyer to take over the drug. While the company insists Zevalin won't come off the market, the move is prompting fear on cancer blogs and from patients considering radioimmunotherapy that the option may disappear.

"Basically, they hit a home run" scientifically, says Kaminski. "The shock wave that goes through here is that if you can't get this to work in the marketplace, what's the sense of developing anything else along this line?"