FDA Approves Celebrex for Rare Genetic Disorder
Dec. 23, 1999 (Atlanta) -- The FDA late Thursday approved the popular anti-inflammatory drug celecoxib (Celebrex) for use against a rare genetic disorder, and it may, in time, find use on a broad scale for cancer prevention and regression.
The disease is called familial adenomatous polyposis (FAP). People with this genetic predisposition develop precancerous polyps in their colons that inevitably lead to colon cancer at a young age. This is the first approved drug treatment for the rare disorder, accounting for less than 1% of colorectal cancers, but the drug's application could prove useful in the broader realm of colorectal cancers.
Celecoxib is a Cox-2 inhibitor, an anti-inflammatory agent with fewer gastrointestinal side effects, approved just a year ago for the management of arthritis pain.
Recent studies have focused on celecoxib's ability to inhibit polyp growth, presumably by inhibiting the growth of blood vessels. These data have sparked a number of studies investigating the ability of Cox-2 inhibitors to treat and prevent cancer.
The FDA approval comes after a 6-month accelerated trial involving 83 patients with FAP. The research showed a 28% reduction in the number of polyps in people taking the drug, compared to those taking a placebo. Further studies are being required of the manufacturer by the FDA to find whether reducing the number of polyps actually does benefit the patient. But these results are very encouraging for people with the disorder.
Lead author of the study Gideon Steinbach, MD, associate internist at M.D. Anderson Cancer Center in Houston, spoke to WebMD earlier this fall. He says this study "is more than three times larger than any of the previous trials. ... For the first time, it demonstrated the efficacy of Cox-2 inhibition in reducing or controlling colorectal adenomas." Steinbach says that in addition to reducing the number of polyps, the treatment also "resulted in a 30% reduction in polyp burden." According to Steinbach, polyp burden is an estimate of the number of polyps, the size of the polyps, and the area of colon affected by polyps. It is analogous, he says, to "reductions in tumor size used in the study of other cancers."
"What is especially interesting about FAP, or persons who have the germ line mutation, is that the development of tumors in FAP is similar to that in the general population with sporadic human colon cancer," Steinbach tells WebMD. "The only difference is that, in sporadic cancer, the mutation is not inherited; it happens randomly. ... By the time tumors develop, the patient has the mutations ... and the tumors progress in a similar fashion, but with many fewer tumors. That's why there is a lot of work with FAP, because it is very likely that drugs effective in FAP could be used in prevention of sporadic colon cancer."