A new drug for osteoarthritis may sidestep the rise in blood pressure common with conventional nonsteroidal anti-inflammatory drugs (NSAIDs), hints a new study funded by the makers of the medication.
Last year the U.S. Food and Drug Administration did not approve naproxcinod, instead asking for more data. If the FDA does give its OK, the drug could be particularly useful for osteoarthritis patients with hypertension.
Naproxcinod is designed to break down into the popular NSAID naproxen, as well as nitric oxide. The latter compound dilates blood vessels, compensating for the blood pressure increase associated with the volume retention from the NSAID.
"Using new technology to link nitric oxide molecules to NSAIDs has shown that some of the 'hypertensive' effects of NSAIDs can be mitigated and, in some patients, that may make the drug more attractive," lead researcher Dr. William White of the University of Connecticut School of Medicine told Reuters Health in an email.
The new study, published online March 7 in The American Journal of Cardiology, was a safety analysis of data pooled from 3 phase III trials, in which 2,734 patients with osteoarthritis of the hip or knee were randomly assigned to receive twice-daily naproxcinod (375 mg or 750 mg), naproxen (500 mg), or placebo.
At baseline, the mean systolic blood pressure was between 125 and 128 mm Hg. After 13 weeks of treatment, naproxcinod had no effect on systolic blood pressure. Naproxen, however, increased systolic blood pressure relative to placebo by an average of 1.4 mm Hg, the authors found.
While the mean differences were small overall, Dr. White noted that the effects were clinically meaningful in patients who were taking angiotensin-converting enzyme inhibitors or angiotensin receptor blockers.
In the 44% of patients who were taking antihypertensive medications, naproxen raised systolic pressure by an average of 4.3 mm Hg compared to the higher dose of naproxcinod.
Based on epidemiologic studies, Dr. White said, a 2 mm Hg difference across the whole population would translate into about a 6% reduction in cardiovascular events over time. A drop of 5 mmHg could trim the rate by 15%, he said.
"Of course, the type of patient matters," said Dr. White. "So these numbers are for older, hypertensive individuals."
Naproxen and both doses of naproxcinod significantly reduced osteoarthritis pain compared to placebo, based on the Western Ontario and McMaster Universities Index pain subscale scores. Naproxen and the 750 mg dose of naproxcinod performed equally; the lower dose of the new drug did not cut pain quite as much as naproxen.
NicOx, the French company that makes the drug, funded the current research. Dr. White said that a decision by European regulatory authorities for approval is expected in April 2011.
Am J Cardiol 2011.
Lynne Peeples • Reuters Health Information © 2011