Improvement of rabies post-exposure prophylaxis for category III exposure

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K08957
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 54030:Infectious disease medicine-related
• Research Institution: Oita University
• Principal Investigator: Nishizono Akira 大分大学, 医学部, 教授 (70218155)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 狂犬病 / 曝露後発症予防治療 / 抗ウイルス薬 / 脳血液関門

Outline of Final Research Achievements

In rabies, which is an incurable disease, severe bites classified as Category III may be fatal even after exposure (PEP) with immunoglobulin preparations (RIG) and continuous rabies vaccines. Effective administration of the antiviral drug Favipiravir was examined for the proposal of PEP regimen which is accessible and more effective for severe bite exposure. In order to update the permeability of the brain blood barrier (BBB) of the drug, modification by cyclodextrin was performed, and the effect was examined, but sufficient results were not obtained. However, it was considered that sufficient prevention effect was obtained by administering favipiravir orally continuously immediately after severe exposure and continuing continuous administration of the vaccine, and it was possible to advocate it as a new PEP regimen.

Free Research Field

ウイルス学

Academic Significance and Societal Importance of the Research Achievements

当初の研究目的で挙げた、狂犬病発症後の脳血液関門の透過性を上昇させる結果は最終的に得られなかったが、これまでに狂犬病ウイルスに対する抗ウイルス効果を確認できている薬剤ファビピラビルをウイルス曝露直後に経口投与し、その後に狂犬病ワクチンの連続接種を行うことで、抗狂犬病免疫グロブリンの効果と遜色無い、100％での発症予防効果を確認できた。このことは、カテゴリーIIIの重度曝露に対する新たな発症後治療のレジメを提示できたものと考えられ、本研究の最終目的の達成に適うと考えられた。