Clinical trial of a new slow-release theophylline preparation (‘Nadm’ SR)

Summary

The absorption of theophylline from a new sustained-release formulation (‘Nuelin’ SR) relative to drug absorption from a conventional formulation was assessed at steady state in a multiple-dose study. Ten healthy adult subjects were studied using a two 5-day period, double-blind, crossover design. Mean trough plasma concentrations of theophylline in the morning (08.00 hours) for each formulation were nearly equivalent from Days 2 to 5 of the study, indicating steady-state plasma levels attained by Day 4 with both formulations. The concentrations, however, were significantly higher after the slow-release formulation. Overall, the plasma level data from this study indicate that the sustained-release tablet has acceptable sustained-release characteristics and should provide both reliable and complete drug absorption, giving it considerable advantage over conventional formulations during chronic therapy of patients with reversible obstructive lung disease.

Key Words::

• Theophylline
• sustained-release preparations
• biological availability