Tailoring the dose of oral corticosteroids in people with severe asthma according to their levels of blood eosinophils can reduce the number of exacerbations, improve asthma symptoms and reduce overall steroid usage, a small Australian pilot study shows.
Speaking to the limbic lead author Peter Wark from the Centre for Asthma and Respiratory Disease at the University of Newcastle said that most patients with severe asthma required long-term oral steroids which had many well-documented side effects.
The aim of their study was to see whether using a simple biomarker – blood eosinophil count – was a better way to adjust steroid doses in these patients compared to usual clinician assessment based on patient symptoms.
The pilot study included 11 patients with severe asthma who were on optimal treatment with inhaled steroids.
All patients had an initial 7-day course of prednisone at 37.5 mg daily before proceeding to a dose adjustment of 15 mg daily for a month if their peripheral eosinophil count (PBE) was less than 0.2 x 109/L. After this point their dosage was titrated up or down depending on whether they maintained the PBE cut off of <0.2 (see paper for precise algorithm).
The research team discovered that adjustment of oral steroid dose using the algorithm was successful in preventing exacerbations, improving asthma control and resulted in lower overall doses of prednisone.
For instance patients had a median of five exacerbations in the six months prior to treatment but during treatment with the algorithm over half of the patients had no exacerbations, two had one exacerbation, and one patient who continued to smoke had three.
The total prednisone dose used in the six-month treatment period resulted in a mean total dose of 509 mg compared to 1820 mg in the previous six months.
While the findings were limited to a small number of severe asthma patients, “the careful characterization and then selection based on a biomarker of both disease activity and treatment response appeared to be successful and easily executed in the clinical setting,” the researchers concluded in their paper published in Respirology.
If confirmed in a larger clinical trial with a control arm the findings could substantially change clinical practice, Wark said.