Extended-release drug formulations for the treatment of epilepsy

ABSTRACT

Introduction: Extended-release (ER) preparations are either available or have been tested for several antiepileptic drugs (AEDs). Indeed, they may be helpful in improving efficacy, tolerability, adherence, compared to the corresponding immediate release (IR) preparations available. The use of ER preparations has been advocated in women of childbearing age and is – depending on the drug – especially helpful in patients who are treated in combination with enzyme inducing AEDs as well as in children.

Areas covered: Clinical and pharmacokinetic studies on ER formulations of AEDs were identified by a PubMed literature research. Further references were added from the authors’ personal knowledge and from the reference lists of the identified studies. Reviews and expert commentaries were included, where necessary.

Expert opinion: Unfortunately, studies providing direct comparisons of ER and IR formulations of a given drug are only available for a handful of drugs. ER preparations are especially helpful in drugs with a short elimination half-life and concentration-depending efficacy and tolerability.

KEYWORDS:

• Epilepsy
• treatment
• antiepileptic drugs
• pharmacokinetics

Article highlights

• Despite considerable progress of epilepsy treatment within the last 25 years, there is still a high number of patients with drug-refractory epilepsy.

• ER formulations especially of AEDs with short half-lives offer some benefit from a theoretical point-of-view.

• Potential benefits of ER formulations include improving adherence and tolerability.

• Besides CBZ, OXC and VPA, there is only very sparse evidence of a clinical benefit of ER-AEDs.

• Switch or comparison studies between IR and ER formulations with clinically meaningful outcome parameters are necessary.

This box summarizes key points contained in the article.

Declaration of Interest

C Brandt has received personal compensation from Actelion, Desitin, Eisai, Otsuka, Pfizer Inc, SKS Pharma, UCB, and USL Pharma for serving on a scientific advisory board or for speaking activities or congress travel. Furthermore, his institution has received financial support for research activities from Otsuka and UCB Pharma. TW May has received financial support from UCB (Monheim, Germany) and Desitin (Hamburg, Germany) for visiting scientific meetings, and has received honoraria for speaking engagements from Eisai (Frankfurt, Germany) and Desitin. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. Peer reviewers on this manuscript have no relevant financial or other relationships to disclose

Additional information

Funding

This manuscript has not been funded.