PRODUCT QUALITY REQUIREMENTS FOR SUSTAINED-RELEASE THEOPHYLLINE PREPARATIONS

In consideration of the narrow therapeutic range and the pharmacology of theophylline (CAS 58-55-9), the pharmaceutic quality of sustained r elease theophylline preparations should be monitored carefully During the last few years, the following pharmacokinetic study programme was established as quality criterion to verify the safety and predictabili ty of theophylline concentration-time profiles: bioequivalence from ba tch to batch, lack of relevant food interaction, lack of relevant gast rointestinal pH or surfactant effects on absorption, pharmacokinetic p rofile following once-a-day and twice-a-day application, and pharmacok inetics in high-clearance patients. Smooth, predictable and safe conce ntration-time profiles can be guaranteed exclusively for preparations which fulfill all these quality criteria. Only such high quality formu lations allow to reduce or even avoid therapeutic drug monitoring and can be considered as safe and effective drugs for the chronic treatmen t of asthma.