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増大特集 てんかんの新しい治療
ファルマコゲノミクス検査によるてんかんのテーラーメイド医療
著者： 吉田秀一12 菅原貴征23 西尾卓広1 兼子直2
所属機関： 1浜松医科大学医学部総合人間科学講座 2弘前大学大学院医学研究科神経精神医学講座 3東北化学薬品生命システム情報研究所
ページ範囲：P.295 - P.299
文献概要
はじめに
抗てんかん薬（antiepileptic drug：AED）による薬物療法は，てんかんの発作抑制を目指す最も有用な治療手段である。一方で，発作型からAEDを選択し，try and errorを繰り返しながらの投与量設定は，発作抑制まで長期間を要し，重篤な副作用も予見できない。加えて，約30％の患者は，十分な治療効果が得られず難治てんかんへと移行するため，さらなる有効な治療戦略の開発が望まれる。
AEDの血中濃度や作用部位（脳内）濃度を規定するcytochrome P450（CYP）などの薬物代謝酵素や薬物排出トランスポーターの薬理遺伝学的研究が飛躍的な進展を遂げ，これら遺伝子多型と薬剤反応性や副作用発現との関連が明らかになりつつある。将来的にこのようなファルマコゲノミクス情報の蓄積は，個々の患者の遺伝情報から最適なAEDおよびその投与量を設定する「テーラーメイド医療」を実現するための鍵となる1）。本稿では，これまでのてんかんのファルマコゲノミクス研究の現状について概説し，「てんかんのテーラーメイド医療」の実現に向けた課題について考察する。
抗てんかん薬（antiepileptic drug：AED）による薬物療法は，てんかんの発作抑制を目指す最も有用な治療手段である。一方で，発作型からAEDを選択し，try and errorを繰り返しながらの投与量設定は，発作抑制まで長期間を要し，重篤な副作用も予見できない。加えて，約30％の患者は，十分な治療効果が得られず難治てんかんへと移行するため，さらなる有効な治療戦略の開発が望まれる。
AEDの血中濃度や作用部位（脳内）濃度を規定するcytochrome P450（CYP）などの薬物代謝酵素や薬物排出トランスポーターの薬理遺伝学的研究が飛躍的な進展を遂げ，これら遺伝子多型と薬剤反応性や副作用発現との関連が明らかになりつつある。将来的にこのようなファルマコゲノミクス情報の蓄積は，個々の患者の遺伝情報から最適なAEDおよびその投与量を設定する「テーラーメイド医療」を実現するための鍵となる1）。本稿では，これまでのてんかんのファルマコゲノミクス研究の現状について概説し，「てんかんのテーラーメイド医療」の実現に向けた課題について考察する。
参考文献
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