Trileptal (oxcarbazepine) tablets and oral suspension
Detailed View: Safety Labeling Changes Approved By FDA Center for Drug Evaluation and Research (CDER) – February 2013 and June 2014
WARNINGS AND PRECAUTIONS
Serious Dermatological Reactions Association with HLA-B*1502
- Patients carrying the HLA-B*1502 allele may be at increased risk for SJS/TEN with Trileptal treatment.
- Human Leukocyte Antigen (HLA) allele B*1502 increases the risk for developing SJS/TEN in patients treated with carbamazepine. The chemical structure of Trileptal is similar to that of carbamazepine. Available clinical evidence, and data from nonclinical studies showing a direct interaction between Trileptal and HLA-B*1502 protein, suggest that the HLA-B*1502 allele may also increase the risk for SJS/TEN with Trileptal.
- The frequency of HLA-B*1502 allele ranges from 2 to 12% in Han Chinese populations, is about 8% in Thai populations, and above 15% in the Philippines and in some Malaysian populations. Allele frequencies up to about 2% and 6% have been reported in Korea and India, respectively. The frequency of the HLA-B*1502 allele is negligible in people from European descent, several African populations, indigenous peoples of the Americas, Hispanic populations, and in Japanese (< 1%).
- Testing for the presence of the HLA-B*1502 allele should be considered in patients with ancestry in genetically at-risk populations, prior to initiating treatment with Trileptal. The use of Trileptal should be avoided in patients positive for HLA-B*1502 unless the benefits clearly outweigh the risks. Consideration should also be given to avoid the use of other drugs associated with SJS/TEN in HLA-B*1502 positive patients, when alternative therapies are otherwise equally acceptable. Screening is not generally recommended in patients from populations in which the prevalence of HLAB*1502 is low, or in current Trileptal users, as the risk of SJS/TEN is largely confined to the first few months of therapy, regardless of HLA B*1502 status.
- The use of HLA-B*1502 genotyping has important limitations and must never substitute for appropriate clinical vigilance and patient management. The role of other possible factors in the development of, and morbidity from, SJS/TEN, such as antiepileptic drug (AED) dose, compliance, concomitant medications, comorbidities, and the level of dermatologic monitoring have not been well characterized.
Post-Marketing and Other Experience
- Metabolism: hypothyroidism