Salmeterol Should Not Be Used Alone, Company Says
In a press release issued Jan. 23, the company said its interim analysis of data from the Serevent Multi-Center Asthma Research Trial indicated that patients who used the long-acting beta2-agonist in addition to their regular therapy tended to fare worse than the other patients.
Compared with the patients who stayed strictly with their regular therapy, a higher number of salmeterol users had a life-threatening episode of asthma or died of the disease, according to the company and the Food and Drug Administration (FDA). The difference between the two treatment groups was not significant in statistical terms but was enough for GlaxoSmithKline to halt the study before enrolling all of the patients the company had planned.
Also contributing to the decision to stop the study early were findings from the interim analysis of data from two subgroups:
- African American users of salmeterol; this subgroup had a significantly higher number of asthma-related life-threatening or fatal episodes than comparable nonusers did.
- Salmeterol users whose regular therapy did not include an inhaled corticosteroid; this group had a significantly higher number of asthma-related deaths than the group that took a placebo in addition to regular therapy.
The company said that, because the actual number of asthma-related events was small, "no conclusions can be drawn from the interim analysis of the data."
Leslie Hendeles, Pharm.D., a professor of pharmacy and pediatrics at the University of Florida, said the recently revealed analysis shows that long-acting beta2-agonists hide the underlying, ongoing inflammation in asthma patients' airways. A government-sponsored study, he said, had already found that asthma therapy with salmeterol alone, without a corticosteroid, was problematic.
Also, he said, the 1997 guidelines (PDF) from the National Asthma Education and Prevention Program Expert Panel recommend that, in asthma patients, long-acting inhaled beta2-agonists be used only with an antiinflammatory medication. Hendeles represents ASHP on the program's coordinating committee.
The findings from the company-sponsored study of salmeterol inhalation aerosol, he said, have "nothing to do with the delivery device" and apply also to the inhalation powder.
Pharmacists, he said, should contact a patient's physician when they notice a prescription for salmeterol but none for an inhaled corticosteroid and advise the addition of the antiinflammatory agent. This course of action, however, is not clear-cut if the patient is African American.
|Update 5 February 2003Hendeles noted that his advice applies only to patients with asthma, not to patients with chronic obstructive pulmonary disease, who should rarely be treated with inhaled corticosteroids.|
The recent findings from the African American subgroup make Hendeles wonder whether pharmacogenomics played a part. He suggested that pharmacists advise salmeterol users who are African American to discuss their asthma status and management regimen with their physician.
FDA, in announcing the halt of the study, said the agency plans to obtain more details from GlaxoSmithKline so as to better interpret the new information about salmeterol's risk to asthma patients. The current labeling for Serevent states that the medication "may be used alone or in combination with inhaled or systemic corticosteroid therapy."