藥物警訊

Potiga (ezogabine): Drug Safety Communication - FDA Determines 2013 Labeling Adequate to Manage Risks of Retinal Abnormalities, Potential Vision Loss, and Skin Discoloration

AUDIENCE: Neurology, Eye Care, Dermatology

ISSUE: Based on reviews of additional safety reports from patients treated with the anti-seizure drug Potiga (ezogabine), the FDA has determined that the potential risks of vision loss due to pigment changes in the retina and of skin discoloration can be adequately managed by following the current recommendations in the Potiga labeling. To further explore any potential long-term consequences of these pigment changes, FDA has required the Potiga manufacturer, GlaxoSmithKline, to conduct a long-term observational study.

FDA review of additional safety reports does not indicate that the pigment changes in the retina observed in some patients affect vision. Skin discoloration associated with the use of Potiga appears to be a cosmetic effect and does not appear to be associated with more serious adverse effects. Therefore, a modification of the Risk Evaluation and Mitigation Strategy (REMS) is not needed at this time to ensure that the benefits of Potiga outweigh the risks of retinal and skin pigment changes. FDA expects that the required long-term observational study will provide further information on whether pigment changes in the retina caused by Potiga can lead to vision loss or other long-term side effects. In addition, the study should provide more information on the relationship between pigment changes in the retina and skin discoloration.

BACKGROUND: Potiga is approved for use in combination with other anti-seizure drugs to treat partial-onset seizures in adult patients who have had an inadequate response to several alternative therapies and for whom the benefits of treatment outweigh the risks.

RECOMMENDATION: Health care professionals should continue to follow the recommendations provided in the Boxed Warning, FDA's most serious type of warning, and the Warnings and Precautions and Indications and Usage sections of the labeling.

Read the MedWatch safety alert, including a link to the FDA Drug Safety Communication, at:
http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHuma...

FDA回顧抗癲癇藥Potiga (ezogabine)之安全性報告，認為因視網膜色素改變造成視力喪失及皮膚變色之風險，目前可依循Potiga仿單中建議進行處置。為了更進一步探討此色素改變之長期潛在影響，FDA已要求廠商進行長期的觀察研究。

FDA檢閱安全性報告表示部分被發現視力受影響之病人並未觀察到有視網膜色素改變。因Potiga引起的皮膚變色為外觀的影響，未出現其他更嚴重之相關副作用。FDA認為目前不需修改藥品風險評估暨管控計畫(REMS)以確認服用此藥品之利益是否大於視網膜及皮膚變色的風險。FDA預期長期觀察研究將提供更多有關Potiga引起之視網膜色素改變是否導致視力喪失或其他長期副作用的資訊，以及視網膜色素改變和皮膚變色之相關性。

Potiga核准用於抗局部癲癇之輔助性治療，可與其他抗癲癇藥品合併使用在因其他替代療法效果不好的成年病人或用於經評估Potiga利大於弊之病人。FDA建議醫療人員應持續遵循仿單中加框警語、注意事項及適應症及用法的指示使用本藥。

相關訊息與連結請參考FDA網址：

http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHuma...

資料來源：美國FDA之藥物安全警訊
資料提供：台大醫院藥劑部