Levetiracetam Modified-Release Matrix Tablet

The development of extended-release (ER) formulations for highly water-soluble high-load drugs presents unique formulation challenges. Due to their rapid dissolution and diffusion characteristics, achieving controlled and predictable drug release often requires careful optimisation of matrix-forming polymers and their functional properties.  

Levetiracetam, a highly soluble and highly permeable antiepileptic drug classified as a BCS Class I compound, was selected as a model drug for this investigation. Because of their relatively short elimination half-life, conventional immediate-release formulations typically require multiple daily doses, creating opportunities for extended-release dosage forms that may improve patient convenience.  

Hypromellose (HPMC) is one of the most widely used polymers in hydrophilic matrix systems, with higher molecular weight grades generally expected to form stronger gel structures and slow drug release. However, for highly water-soluble APIs, the impact of polymer viscosity on release kinetics is not always fully understood.  

To investigate this relationship, IMCD's Pharmaceutical Technical Centre (PTC) in Istanbul developed a series of levetiracetam ER matrix tablets incorporating different HPMC viscosity grades while maintaining a constant polymer concentration. The objective was to evaluate how HPMC molecular weight influences dissolution behaviour, release kinetics and drug release mechanisms in hydrophilic matrix tablets. 

This formulation concept is ideally suited for: 

This study aimed to determine the relationship between HPMC molecular weight and extended-release performance in a highly water-soluble model drug. Formulators would benefit from enhanced formulation flexibility, reduced development risk, and actionable insights to support the design of robust and predictable modified-release products.