Saturday, September 18, 2010

New Drugs Stir Debate on Basic Rules of Clinical Trials - NYTimes.com

Growing up in California's rural Central Valley, the two cousins spent summers racing dirt bikes and Christmases at their grandmother's on the coast. Endowed with a similar brash charm, they bought each other matching hardhats and sought iron-working jobs together. They shared a love for the rush that comes with hanging steel at dizzying heights, and a knack for collecting speeding tickets.

And when, last year, each learned that a lethal skin cancer called melanoma was spreading rapidly through his body, the young men found themselves with the shared chance of benefiting from a recent medical breakthrough.

Only months before, a new drug had shown that it could safely slow the cancer's progress in certain patients. Both cousins had the type of tumor almost sure to respond to it. And major cancer centers, including the University of California, Los Angeles, were enrolling patients for the last, crucial test that regulators required to consider approving it for sale.

"Dude, you have to get on these superpills," Thomas McLaughlin, then 24, whose melanoma was diagnosed first, urged his cousin, Brandon Ryan. Mr. McLaughlin's tumors had stopped growing after two months of taking the pills.

But when Mr. Ryan, 22, was admitted to the trial in May, he was assigned by a computer lottery to what is known as the control arm. Instead of the pills, he was to get infusions of the chemotherapy drug that has been the notoriously ineffective recourse in treating melanoma for 30 years.

Even if it became clear that the chemotherapy could not hold back the tumors advancing into his lungs, liver and, most painfully, his spine, he would not be allowed to switch, lest it muddy the trial's results.

"I'm very sorry," Dr. Bartosz Chmielowski, the U.C.L.A. oncologist treating both cousins, told Mr. Ryan's mother, Jan. He sounded so miserable that afternoon that Mrs. Ryan, distraught, remembers pausing to feel sorry for the doctor.

Controlled trials have for decades been considered essential for proving a drug's value before it can go to market. But the continuing trial of the melanoma drug, PLX4032, has ignited an anguished debate among oncologists about whether a controlled trial that measures a drug's impact on extending life is still the best method for evaluating hundreds of genetically targeted cancer drugs being developed.

Defenders of controlled trials say they are crucial in determining whether a drug really does extend life more than competing treatments. Without the hard proof the trials can provide, doctors are left to prescribe unsubstantiated hope — and an overstretched health care system is left to pay for it. In melanoma, in particular, no drug that looked promising in early trials had ever turned out to prolong lives.

PLX4032 shrinks tumors in the right patients, for a limited time. But would those who took it live longer? No one knew for sure.

"I think we have to prove it," said Dr. Paul B. Chapman, a medical oncologist at Memorial Sloan-Kettering Cancer Center who is leading the trial. "I think we have to show that we're actually helping people in the long run."

But critics of the trials argue that the new science behind the drugs has eclipsed the old rules — and ethics — of testing them. They say that in some cases, drugs under development, PLX4032 among them, may be so much more effective than their predecessors that putting half the potential beneficiaries into a control group, and delaying access to the drug to thousands of other patients, causes needless suffering.

"With chemotherapy, you're subjecting patients to a toxic treatment, and the response rates are much lower, so it's important to answer 'Are you really helping the patient?' " said Dr. Charles L. Sawyers, chairman of human oncology at Sloan-Kettering. "But with these drugs that have minimal side effects and dramatic response rates, where we understand the biology, I wonder, why do we have to be so rigorous? This could be one of those defining cases that says, 'Look, our system has to change.' "

Dr. Richard Pazdur, director of the cancer drug office at the Food and Drug Administration, said in a recent interview that the new wave of drugs in development — especially for intractable cancers like melanoma — might require individual evaluation. "This is an unprecedented situation that will, hopefully, be increasingly common, and it may require a regulatory flexibility and an open public discussion," he said.

And doctors say that for them, the new wave of cancer drugs is intensifying the conflict between their responsibility to their patients and their commitment to gathering scientific knowledge for generations of the critically ill.

Of course, no single pair of patients can fairly represent the outcomes of a trial whose results are not yet known. Rather, the story of Thomas McLaughlin and Brandon Ryan is one of entwined paths that suddenly diverged, with a roll of the dice.

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http://www.nytimes.com/2010/09/19/health/research/19trial.html?src=twr