Monday, June 2, 2008
The Washington Post reports on a new study showing some extra positives from taking high doses of Celebrex, it may help prevent lung cancer in heavy smokers. Julie Steenhuysen writes,
A high dose of the arthritis drug Celebrex showed early signs that it may help prevent lung cancer in heavy smokers, U.S. researchers said on Sunday. The Pfizer Inc <PFE.N> drug, also known as celecoxib, works by blocking the COX-2 enzyme that causes inflammation, which has been linked with cancer.
A six-month study of 212 current or heavy smokers found a reduction in a specific type of precancerous change in lung cells in people who took a high dose of Celebrex compared with those who took a placebo. None of the study participants had any heart-related problems such as those with Merck & Co Inc's <MRK.N> now withdrawn arthritis drug Vioxx, another COX-2 inhibitor. . . .
"This is not a study where we go tell someone who is a heavy smoker to start taking Celebrex to prevent lung cancer," Kim said in an interview. Lung cancer is the leading cause of cancer death in the United States, according to the American Cancer Society. In 2008, about 215,000 people will be diagnosed with lung cancer and about 114,000 people will die from it. . . .
Rather than a direct measure of cancer prevention, which could take many years, Kim said the researchers were looking for early changes in the body that might suggest the drug could reduce the chances of developing lung cancer.
The researchers tested Celebrex in the study because studies in cells, mice and in people have shown the COX-2 enzyme is present at higher than normal levels in lung cancer and in precancerous lesions of the lung, Kim said. COX-2 is thought to play a role in the development of blood vessels that feed tumors. Kim's study measured levels of the Ki-67 protein, a marker for cell growth. The researchers wanted to see if Celebrex had an impact on levels of this protein in tissue samples taken from the lungs of heavy smokers.
At the beginning of the study, the researchers took lung samples from six predetermined areas of the lung. People in the study either got a 200 milligram or a 400 milligram dose of Celebrex twice a day, or a placebo. After three months, they took more lung samples, and they took samples again at six months. Kim said the group that got the higher dose of Celebrex saw a reduction in levels of the Ki-67 protein. Kim said it will be important to find better ways of identifying people who are at the highest risk for lung cancer for whom the benefits of taking a high-dose COX-2 inhibitor would outweigh any potential heart risks.