Pfizer's cancer drug crizotinib was able to shrink tumors of non-small-cell lung cancer patients whose tumors carried a specific genetic mutation, EML4-ALK, which fuses two genes. The early-stage study results were published in the New England Journal of Medicine.
More people die from lung cancer than any other type of cancer, the Centers for Disease Control and Prevention notes. In 2006, it accounted for more deaths than breast cancer, prostate cancer and colon cancer combined. Just over 200,000 people were diagnosed with lung cancer in 2006, and nearly 160,000 died from lung cancer that year.
"It Is Gratifying"
In the crizotinib trial, 82 patients had the gene mutation. The tumors of 46 patients who took the oral drug shrank by more than 30%. One patient's tumor disappeared entirely. That's 57% of patients who had either a complete or partial response to treatment. Crizotinib stopped tumor growth in 27 of the patients, or 33%. The study authors estimated that for 72% of patients, the disease wouldn't worsen for six months.
"It is gratifying to learn of responses like those seen in our study of crizotinib (PF-02341066), especially when you consider that most patients had already received two or more therapies by the time they entered the trial," said Dr. Eunice Kwak, from Harvard Medical School and lead author of the study.
But, as the study also notes, patients without the specific abnormality didn't have a response to treatment. And unfortunately, only 2% to 7% of people with non-small-cell lung cancer have the mutation. Further, another study published in the NEJM reported a patient who developed resistance to the drug. Still, 5% of lung cancer cases is about 10,000 patients in the U.S.
"While this is a Phase I study, the high response rates observed in patients with ALK-positive (lung cancer) who received crizotinib suggest that we may be one step closer to the development of 'precision' or 'personalized' cancer treatments that target specific genetic factors that drive certain tumors," said Pfizer's Dr. Mace Rothenberg in a statement.
A Phase III trial of the drug has already begun. And according to Reuters, Pfizer said it planned to start submitting data for approval of the drug to the U.S. Food and Drug Administration early next year.