Rebirth of the Cox-2 Inhibitors

You will recall that the Cox-2 inhibitors were brought down by the discovery of serious cardiovascular toxicity during clinical studies of their use in trying to prevent pre-malignant colon tumors. Now two of these studies have been completed, and their results reported at an American Association for Cancer Research meeting.

First, the toxicity: of a total of 46 cardiovascular ‘events’ (heart attack, severe angina, sudden death, or stroke), there were 7 in the placebo group, 16 with low-dose Celebrex, and 23 with high-dose Celebrex; that’s a frequencies of 1%, 2.3% and 3.4%, respectively.

Now, effectiveness: the number of adenomas (benign, polyp-like tumors) in patients at high risk of colorectal cancer was reduced from 65% (in the placebo group) by half in those taking Celebrex. And there were 66% fewer advanced tumors with help of the drug.

Findings in the second study were similar. It’s hard to know what to make of these results. Until a ‘better’ Cox-2 inhibitor is found (i.e. one with less cardiotoxicity and greater anti-colon tumor effectiveness) the researchers believe the use of Celebrex (and similar drugs) must be reserved for those people at high risk of colorectal cancer without any major cardiovascular risk factors.