{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,27]],"date-time":"2026-06-27T10:31:12Z","timestamp":1782556272413,"version":"3.54.5"},"reference-count":26,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2022,9,7]],"date-time":"2022-09-07T00:00:00Z","timestamp":1662508800000},"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>My collaboration with Prof. Anton\u00edn Hol\u00fd, that spans a period of 3\u20134 decades (1976\u20132012), led to the discovery of several acyclic nucleoside phosphonates (ANPs) which were clinically developed by Gilead Sciences: cidofovir, adefovir, and tenofovir. The latter was further converted to two orally bioavailable prodrug forms, TDF and TAF, and both TDF and TAF were further combined with other antiviral drugs, thus giving rise to a broad array of antiviral drug combinations for the treatment of HIV infections. TDF and TAF are both available for the treatment of hepatitis B virus (HBV) infections, and, in combination with emtricitabine, also applicable as Truvada\u00ae and Descovy\u00ae, respectively, for the prophylaxis of HIV infections.<\/jats:p>","DOI":"10.3390\/v14091978","type":"journal-article","created":{"date-parts":[[2022,9,8]],"date-time":"2022-09-08T20:50:27Z","timestamp":1662670227000},"page":"1978","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["The Elegance of the Acyclic Nucleoside Phosphonates (ANPs), Honorary Tribute to Anton\u00edn Hol\u00fd, Who Passed Away on 16 July 2012, at the 10th Anniversary of His Death"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2985-8890","authenticated-orcid":false,"given":"Erik","family":"De Clercq","sequence":"first","affiliation":[{"name":"Rega Institute for Medical Research, Herestraat 49, B-3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"563","DOI":"10.1126\/science.200.4341.563","article-title":"(S)-9-(2,3-dihydroxypropyl)adenine: An aliphatic nucleoside analog with broad-spectrum antiviral activity","volume":"200","author":"Descamps","year":"1978","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"583","DOI":"10.1038\/272583a0","article-title":"9-(2-hydroxyethoxymethyl) guanine activity against viruses of the herpes group","volume":"272","author":"Schaeffer","year":"1978","journal-title":"Nature"},{"key":"ref_3","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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