Abstracts

Rationale: We wished to assess current prescribing practices in newly diagnosed focal epilepsy. The Human Epilepsy Project (HEP) is a prospective, observational study whose goal is to identify markers of treatment response in newly diagnosed focal epilepsy. We assessed the AED exposures over the first 2 years of treatment. Methods: Subjects were recruited from 33 sites in the US, Australia, Austria, and Finland. Inclusion criteria included: focal epilepsy, within 4 months of initial diagnosis, and all data related to AED therapy initiation available. 450 subjects have been enrolled. We selected those initiated on monotherapy and with two years or more data since AED start (N=403).  We also excluded subjects who did not have medical records available (10), did not have a known treatment start date (65), or had missing data (64), leaving 264 for analysis. We assessed only the AEDs used in the first 2 years. Results: 157 (59.5%) initiated levetiracetam (LEV), 49 (18.6%) lamotrigine (LTG), 21 (8%) oxcarbazepine (OXC), 11 (4.2%) phenytoin, 5 (1.9%) topiramate, 12 (4.5%) carbamazepine, (CBZ)  2 (0.8%) lacosamide, 5 (1.9%) valproic acid, 1 (0.4%) pregabalin, and 1 (0.4%) zonisamide.Of the 157 started on LEV, 63 (31.6%) remained on the drug in monotherapy, 76 (48%) switched to another AED, 12 (7.6%) added an AED in conjunction, and 6 (3.8%) ceased AED usage. Of the 49 started on LTG,  34 (69.4%) remained on the drug in monotherapy,  10 (20%) switched to another AED, 4 (8.2%) added an AED in conjunction, and 1 (2%) ceased AED usage. Of the 21 started on OXC, 11 (52.4%) remained on the drug in monotherapy, 9(43%) switched to another AED, 1 (4.8%) added an AED in conjunction. Of the 12 started on CBZ, 6 (50%) remained on the drug for at least 2 years, 3 (25%) switched AEDs, and 3 (25%) ceased usage. Combining the sodium channel blockers LTG, OXC, and CBZ, (PHT excluded since often d/c’d after start in the ER) 51/82 (62%) of patients remained on initial monotherapy. By the end of the study, pts were receiving the following AEDs alone or in combination: LEV 36.0%, LTG 37.5%, CBZ 6.8%, OXC 17.0%, PHT 0.8%, topiramate 2.3%, lacosamide 7.2%, valproic acid 1.9%, zonisamide 4.9%, lorazepam 0.8%, clobazam 0.4%, clonazepam 0.4%. 79.9% of patients were on monotherapy, 16.7% on polytherapy, and 2.7% discontinued AED usage. Conclusions: LEV is by far the most commonly initiated AED for focal epilepsy (3 X more than any other single AED). The likelihood of remaining on initial monotherapy was twice as high for a sodium channel blocker as for LEV in the first 2 years of treatment. (P=.001) Funding: The HEP study is supported by the Epilepsy Study Consortium (ESCI), a non-profit organization dedicated to accelerating the development of new therapies in epilepsy to improve patient care. The funding provided to ESCI to support HEP comes from industry, philanthropy, and foundations (UCB Pharma, Eisai, Pfizer, Lundbeck, Sunovion, The Andrews Foundation, The Vogelstein Foundation, Finding A Cure for Epilepsy and Seizures [FACES], Friends of Faces and others).