Clinical Evaluation of Sustained-Release Theophylline Administered Three Times a Day with a Controlled-Release Theophylline Dosed Twice Daily in Children with Asthma

Twenty asthmatic children aged 7-12 years were enrolled in an open, sequential crossover, clinical comparison of long-acting theophylline formulations. The efficacy and safety of sustained-released theophylline (SR) preparations taken t.i.d. and a controlled-release theophylline (CR) formulation administered b.i.d. were compared in children whose asthma had previously been uncontrolled on twice-daily SR theophylline. Based on categorical ratings of none, mild, moderate, or severe, both physician and patient subjectively assessed symptom control: cough, wheeze, chest tightness, and dyspnea. Patients monitored peak flow at home three times daily. At the end of each of the two study phases, patients were examined 8-12 hours after dosing. Spirometry was used to measure FEV₁ and PEFR. The CR preparation dosed twice daily was equal in effectiveness to the patients' previous theophylline regimens given t.i.d. when either objective or subjective parameters of pulmonary function were compared. No patient experienced an adverse drug reaction that was considered directly drug-related during either study phase. Seventeen of 20 participating patients (85%) preferred the CR theophylline formulation, presumably because of its twice-daily dosing schedule.