Medical research finds link between bisphosphonates, irregular heartbeat
WINSTON-SALEM, N.C. New research at Wake Forest University School of Medicine released Monday evaluated the link between a common class of drugs used to prevent bone fractures in osteoporosis patients and the development of irregular heartbeat.
Researchers found that bisphosphonate use was associated with a significant increase in the incidence of “serious” heart rhythm disturbances, classified by hospitalization, disability or death resulting from the condition. However, when they included “non-serious” cases in their analysis, they found no overall increased risk of atrial fibrillation.
“Our findings were discordant, with conflicting results,” stated Sonal Singh, an assistant professor of internal medicine and lead investigator for the study. “The challenge now is to figure out what it all means.”
Early studies indicated that the use of bisphosphonates might cause problems with heart rhythm, or atrial fibrillation, which increases the risk for stroke or heart attack. For the study published this month, researchers analyzed the data from previous observational studies and clinical trials to determine the link between bisphosphonate therapy and irregular heart beat.
“Some trials show there could be a potential link between the use of bisphosphonates and the development of serious heart rhythm problems, but in our study the link wasn’t conclusive,” Singh said. “So we urge that additional investigations be conducted.”
Bisphosphonates, found in prescription drugs including Boniva (ibandronate sodium), Fosomax (alendronate), Reclast (zoledronic acid) and Actonel (risedronate sodium), inhibit the breakdown of bones, which reduces the risk of fractures, especially those of the spine and hips in older patients. The first such drugs were approved for use in the mid-1990s.
In the clinical trials reviewed, medical records of more than 13,000 patients who had osteoporosis or fractures and were given bisphosphonates were compared to the records of more than 13,000 patients who received a placebo during study participation. Researchers were looking for the incidence of irregular heartbeat first, and then stroke or death caused by stroke or heart attack as a secondary outcome. The patient files reviewed were primarily of women who were treated with bisphosphonates and were generally in their early 70s, according to the study.
“We found no risk of stroke and cardiovascular mortality in the trials,” Singh said. “That was very reassuring.”
Given these results, physicians should not change they way they prescribe the drugs for the majority of patients with osteoporosis, Singh said, and patients should not stop taking them. He cautioned, however, that patients with pre-existing heart conditions and those with risk factors for rhythm disturbance should be especially vigilant for the development of atrial fibrillation, and doctors should continue to closely monitor patients at risk for atrial fibrillation who are taking bisphosphonates.
The study’s findings appear in the current issue of Drug Safety, a publication of the International Society of Pharmacovigilance covering the safe and proper use of medicines.
FDA to host meeting regarding ‘economically motivated adulteration’
WASHINGTON The Food and Drug Administration on May 1 will host a meeting around “economically motivated adulteration,” the association announced Monday through the Federal Register.
“The purpose of the meeting is to stimulate and focus a discussion about ways in which the food (including dietary supplements and animal food), drug, medical device and cosmetic industries, regulatory agencies and other parties can better predict and prevent economically motivated adulteration with a focus on situations that pose the greatest public health risk,” the agency stated.
Zegerid new formulation filed; OTC switch of original still in play
SAN DIEGO Santarus, a specialty pharmaceutical company, on Monday announced that the Food and Drug Administration has accepted for filing the company’s drug application for a new tablet formulation to add to its Zegerid (omeprazole/sodium bicarbonate) family of branded prescription pharmaceutical products.
“In late January, we submitted to the FDA an NDA for an immediate release tablet formulation of Zegerid, which combines omeprazole with a mix of buffers,” Gerald Proehl, Santarus president and CEO, told analysts last month. “We believe this new tablet has the potential to provide features and benefits that … will be important to physicians and their patients with GERD. Our objectives [are] to have the new Zegerid tablet product commercially available in the United States in the fourth quarter of 2009.”
Pursuant to Prescription Drug User Fee Act guidelines, Santarus expects the FDA will complete its review or otherwise respond to the NDA by Dec. 4.
In connection with the FDA’s acceptance for filing of the NDA for a new tablet formulation, Santarus is providing notice to the NDA holder for Prilosec (omeprazole) delayed-release capsules and related patent holders that the new tablet formulation does not infringe the patents listed in the Orange Book for Prilosec or that those patents are invalid.
On a separate front, Schering-Plough, in partnership with Santarus, is currently seeking to switch the current Zegerid formulation (20-mg) from prescription-only to over-the-counter. Schering-Plough HealthCare Products received a Complete Response Letter regarding that switch application in January.
“Santarus believes that the response will be based on further analysis of existing data,” Proehl said. “While we can’t predict with certainty what the FDA will require if the analysis of the existing data is acceptable to the FDA, Santarus does not believe there will be a need for any additional clinical study.”