Dual cross-linked pulsatile beads for chronotherapy of asthma: development and evaluation

Area of Science:

• Pharmaceutical Sciences
• Drug Delivery Systems
• Materials Science

Background:

• Asthma management often requires precise drug release timing.
• Chronotherapy aims to align drug delivery with circadian rhythms for improved efficacy.
• Pulsatile drug delivery systems can provide delayed release to match physiological needs.

Purpose of the Study:

• To develop and characterize dual-cross-linked beads for pulsatile theophylline release.
• To achieve a specific lag time for chronotherapeutic application in asthma.
• To evaluate the in vitro and in vivo performance of the formulated beads.

Main Methods:

• Ionic gelation technique using sodium alginate and Delonix regia gum (DRG).
• Dual cross-linking with calcium chloride and aluminum chloride solutions.
• Coating with Eudragit L & S 100 for controlled lag time.
• In vitro drug release studies and in vivo radio imaging in rabbits.

Main Results:

• Theophylline-loaded beads exhibited pulsatile release with a lag time of 5–7 hours.
• Beads remained intact for up to 6 hours, ensuring delayed drug availability.
• In vitro release profiles were consistent with the intended chronotherapeutic application.
• In vivo radio imaging studies in rabbits corroborated the in vitro findings.

Conclusions:

• Dual-cross-linked beads formulated with DRG and Eudragit L & S 100 provide a promising pulsatile delivery system for theophylline.
• The achieved lag time is suitable for managing early morning asthmatic symptoms.
• This approach supports chronotherapy for chronic asthma patients, potentially improving treatment outcomes.