Comparison of a new sustained-release theophylline preparation, TheoBeads, with Theo-Dur tablets in children with asthma.

ABSTRACT

A new, slow-release theophylline formulation for children, TheoBeads, which has the potential for once-daily dosing, has become available. We report the results of a study of pediatric patients whose medication was changed from Theo-Dur tablets b.i.d. to TheoBeads q.d. Forty-nine children with asthma (aged 6-12 years) were treated with b.i.d. Theo-Dur to produce therapeutic maximum and minimum concentration levels (i.e., 8-20 micrograms/ml). Approximately half the patients were then transferred to TheoBeads given q.d. at the same total daily dose and retitrated; seven patients needed to be changed to b.i.d. dosing due to unacceptable fluctuations. The other half of the patients continued on b.i.d. Theo-Dur. Following at least 5 days of steady-state dosing, serum theophylline levels were assayed over a 24-hour period. It was found that 1. Children changed to q.d. TheoBeads showed no change in their overall asthma control based on clinical diary entries and peak flow measurements. 2. Lower Cmax and Cmin theophylline levels and a smaller area under the curve were noted for patients taking q.d. TheoBeads compared to those taking b.i.d. Theo-Dur. 3. Administration of TheoBeads q.d. resulted in a significantly larger overall peak-to-trough fluctuation and a higher percentage of patients with subtherapeutic theophylline levels in the second 12-hour period than did b.i.d. Theo-Dur administration. In summary, when children receiving b.i.d. Theo-Dur were transferred to q.d. TheoBeads, they did not maintain even and sustained therapeutic theophylline levels, although asthma control was not adversely affected during the short period of observation.