Full-Length Original Research
Potential role for human P-glycoprotein in the transport of lacosamide
Version of Record online: 29 MAR 2013
Wiley Periodicals, Inc. © 2013 International League Against Epilepsy
Volume 54, Issue 7, pages 1154–1160, July 2013
How to Cite
Zhang, C., Chanteux, H., Zuo, Z., Kwan, P. and Baum, L. (2013), Potential role for human P-glycoprotein in the transport of lacosamide. Epilepsia, 54: 1154–1160. doi: 10.1111/epi.12158
- Issue online: 1 JUL 2013
- Version of Record online: 29 MAR 2013
- Manuscript Accepted: 19 FEB 2013
- UCB Pharma
Antiepileptic drugs (AEDs) do not effectively treat 30–40% of patients with epilepsy. Export of AEDs by P-glycoprotein (Pgp, ABCB1, or MDR1), which is overexpressed in the blood–brain barrier in drug-resistant patients, may be a mechanism for resistance to AEDs. For most recently approved AEDs, whether they are transported by Pgp is unknown. We investigated whether a new AED, lacosamide (LCM), is a substrate of human Pgp.
LLC-PK1 and MDCKII cells transfected with the human MDR1 gene were used to determine the substrate status of LCM in concentration equilibrium transport assays (CETAs). An equal concentration of drug was initially loaded in both the apical and basal chambers, and the concentration in both chambers was measured up to 4 h. The experiments were repeated in the presence of the Pgp inhibitors verapamil and tariquidar. Caco-2 assays were used to determine the intrinsic permeability and efflux ratio of LCM as well as its potential to inhibit digoxin, a Pgp substrate.
Lacosamide was transported by MDR1-transfected cells from basolateral to apical sides. The efflux of LCM could be completely blocked by verapamil or tariquidar. In Caco-2 assays, LCM showed high permeability without a significant efflux ratio; it did not inhibit digoxin, a Pgp substrate.
Although LCM is a substrate of Pgp in CETA, Caco-2 data demonstrated that passive diffusion should play a major role in the overall disposition of LCM. The critical role of Pgp should be addressed in vivo.