{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T16:52:34Z","timestamp":1792515154151,"version":"4.5.0"},"reference-count":50,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,8,5]],"date-time":"2021-08-05T00:00:00Z","timestamp":1628121600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Acyclovir, valacyclovir, and famciclovir are used for the treatment of herpes simplex virus (HSV) and varicella-zoster virus (VZV) infections. Helicase-primase inhibitors (HPIs) inhibit replication fork progression that separates double DNA strands into two single strands during DNA synthesis. The HPIs amenamevir and pritelivir have novel mechanisms of anti-herpetic action, and their once-daily administration has clinical efficacy for genital herpes. Among HPIs, amenamevir has anti-VZV activity. The concentrations of HSV-1 and VZV required for the 50% plaque reduction of amenamevir were 0.036 and 0.047 \u03bcM, respectively. We characterized the features of amenamevir regarding its mechanism, resistance, and synergism with acyclovir. Its antiviral activity was not influenced by the viral replication cycle, in contrast to acyclovir. A clinical trial of amenamevir for herpes zoster demonstrated its non-inferiority to valacyclovir. To date, amenamevir has been successfully used in over 1,240,000 patients with herpes zoster in Japan. Post-marketing surveillance of amenamevir in Japan reported side effects with significant potential risk identified by the Japanese Risk Management Plan, including thrombocytopenia, gingival bleeding, and palpitations, although none of these were serious. The clinical efficacy and safety profiles of amenamevir were established in patients with herpes zoster. Therefore, amenamevir as an HPI opens a new era of anti-herpes therapy.<\/jats:p>","DOI":"10.3390\/v13081547","type":"journal-article","created":{"date-parts":[[2021,8,5]],"date-time":"2021-08-05T09:35:32Z","timestamp":1628156132000},"page":"1547","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":90,"title":["Amenamevir, a Helicase-Primase Inhibitor, for the Optimal Treatment of Herpes Zoster"],"prefix":"10.3390","volume":"13","author":[{"given":"Kimiyasu","family":"Shiraki","sequence":"first","affiliation":[{"name":"Faculty of Nursing, Senri Kinran University, 5-25-1 Fujishirodai, Suita, Osaka 565-0873, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shinichiro","family":"Yasumoto","sequence":"additional","affiliation":[{"name":"Yasumoto Dermatology Clinic, Tsukushino, Fukuoka 818-0083, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nozomu","family":"Toyama","sequence":"additional","affiliation":[{"name":"Toyama Dermatologic Clinic, Aburatsu, Nichinan City, Miyazaki 887-0001, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroaki","family":"Fukuda","sequence":"additional","affiliation":[{"name":"Maruho Co., Ltd., Nakatsu, Osaka 531-0071, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5716","DOI":"10.1073\/pnas.74.12.5716","article-title":"Selectivity of action of an antiherpetic agent, 9-(2-hydroxyethoxymethyl) guanine","volume":"74","author":"Elion","year":"1977","journal-title":"Proc. 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