{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T15:49:45Z","timestamp":1791474585744,"version":"4.3.4"},"reference-count":36,"publisher":"American Society for Microbiology","license":[{"start":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T00:00:00Z","timestamp":1791417600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T00:00:00Z","timestamp":1791417600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.asm.org\/non-commercial-tdm-license"}],"funder":[{"DOI":"10.13039\/100009947","name":"Merck Sharp and Dohme","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100009947","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["journals.asm.org"],"crossmark-restriction":true},"short-container-title":["Antimicrob Agents Chemother"],"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title\/>\n                    <jats:p>\n                      Ulonivirine is a non-nucleoside reverse transcriptase inhibitor in clinical development for once-weekly oral treatment of HIV-1 in combination with islatravir. This open-label, 3-period, Phase 1 study (MK-8507-016, NCT06619678) in adults without HIV evaluated the potential drug-drug interactions (DDIs) between ulonivirine and islatravir. In Period 1, participants received islatravir 2 mg on Day 1. In Period 2, participants received ulonivirine 200 mg on Days 1 and 8. In Period 3, a single dose of islatravir 2 mg was co-administered with ulonivirine 200 mg 7 days after the Day 8 dose in Period 2, followed by four doses of ulonivirine 200 mg once weekly. Thirty-six participants (58% female, 67% White, median age 43 years) were enrolled. Plasma pharmacokinetics of islatravir and ulonivirine were similar with and without coadministration. The 90%\n                      <jats:italic toggle=\"yes\">CIs<\/jats:italic>\n                      for geometric mean ratios of co-administration versus single administration of islatravir (AUC\n                      <jats:sub>0-168<\/jats:sub>\n                      , 1.06 [1.02\u20131.09]; C\n                      <jats:sub>168<\/jats:sub>\n                      , 1.05 [0.98\u20131.12]; C\n                      <jats:sub>max<\/jats:sub>\n                      , 1.10 [1.02\u20131.19]) and ulonivirine (AUC\n                      <jats:sub>0-168<\/jats:sub>\n                      , 1.07 [1.05\u20131.09]; C\n                      <jats:sub>168<\/jats:sub>\n                      , 1.08 [1.04\u20131.12]; C\n                      <jats:sub>max<\/jats:sub>\n                      , 1.03 [0.98\u20131.07]) were within standard bioequivalence bounds (0.8\u20131.25). During Period 3 (co-administration with ulonivirine), intracellular ISL-triphosphate AUC\n                      <jats:sub>0-168<\/jats:sub>\n                      , AUC\n                      <jats:sub>0-inf<\/jats:sub>\n                      , C\n                      <jats:sub>max<\/jats:sub>\n                      , and C\n                      <jats:sub>168<\/jats:sub>\n                      were approximately 21%, 15%, 16%, and 10% lower, respectively, compared with ISL alone. These differences may in part reflect variability in peripheral blood mononuclear cell counts. Adverse events, laboratory test results, and other safety parameters were comparable among all three periods. In conclusion, no clinically meaningful DDIs were observed between ulonivirine 200 mg and islatravir 2 mg, supporting continued development of this combination for HIV-1 treatment.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1128\/aac.00676-26","type":"journal-article","created":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T14:51:52Z","timestamp":1791471112000},"update-policy":"https:\/\/doi.org\/10.1128\/asmj-crossmark-policy-page","source":"Crossref","is-referenced-by-count":0,"title":["Open-label Phase 1 study to evaluate drug-drug interactions between ulonivirine and islatravir in adults without HIV"],"prefix":"10.1128","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3591-7041","authenticated-orcid":true,"given":"Jesse C.","family":"Nussbaum","sequence":"first","affiliation":[{"name":"Merck & Co., Inc.","place":["Rahway, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michelle M.","family":"Pham","sequence":"additional","affiliation":[{"name":"Merck & Co., Inc.","place":["Rahway, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-3300-1794","authenticated-orcid":true,"given":"Ryan","family":"Vargo","sequence":"additional","affiliation":[{"name":"Merck & Co., Inc.","place":["Rahway, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yang","family":"Liu","sequence":"additional","affiliation":[{"name":"Merck & Co., Inc.","place":["Rahway, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilias","family":"Triantafyllou","sequence":"additional","affiliation":[{"name":"Merck & Co., Inc.","place":["Rahway, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Natasha","family":"Boyette","sequence":"additional","affiliation":[{"name":"Merck & Co., Inc.","place":["Rahway, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8403-267X","authenticated-orcid":true,"given":"Randolph P.","family":"Matthews","sequence":"additional","affiliation":[{"name":"Merck & Co., Inc.","place":["Rahway, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8334-4815","authenticated-orcid":true,"given":"Marian","family":"Iwamoto","sequence":"additional","affiliation":[{"name":"Merck & Co., Inc.","place":["Rahway, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9111-4550","authenticated-orcid":true,"given":"Gillian","family":"Gillespie","sequence":"additional","affiliation":[{"name":"Merck & Co., Inc.","place":["Rahway, USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"235","published-online":{"date-parts":[[2026,10,8]]},"reference":[{"key":"e_1_3_4_2_2","unstructured":"UNAIDS. 2025. 2025 Fact sheet - global HIV statistics. Available from: https:\/\/www.unaids.org\/sites\/default\/files\/media_asset\/UNAIDS_FactSheet_en.pdf. Retrieved 6 Feb 2026."},{"key":"e_1_3_4_3_2","doi-asserted-by":"publisher","DOI":"10.1080\/13548506.2014.945601"},{"key":"e_1_3_4_4_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pmed.1002183"},{"key":"e_1_3_4_5_2","unstructured":"US Food and Drug Administration (FDA). 2025. CABENUVA (Cabotegravir) prescribing information. Available from: https:\/\/www.accessdata.fda.gov\/drugsatfda_docs\/label\/2025\/212888Orig1s017lbl.pdf. Retrieved 5 Aug 2026."},{"key":"e_1_3_4_6_2","unstructured":"ViiV Healthcare. Dosing and administration guide. Available from: https:\/\/cabenuvahcp.com\/in-your-practice\/dosing-and-administration\/#dosing-guide. Retrieved 55 AugAugust 2026. 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Accessed 16 September 2025. https:\/\/www.croiconference.org\/abstract\/mk-8591-potency-and-pk-provide-high-inhibitory-quotients-low-doses-qd-and-qw."},{"key":"e_1_3_4_15_2","volume-title":"March 6-10, 2021; Boston, MA, USA. Oral Abstract 129","author":"Diamond TL","unstructured":"Diamond TL, Lai M-T, Feng M, Xu M, Sachs NA, Hazuda D, Asante-Appiah E, Grobler JA. Resistance profile of MK-8507, a novel NNRTI suitable for weekly oral HIV treatment. March 6-10, 2021; Boston, MA, USA. Oral Abstract 129. . 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Conference on Retroviruses and Opportunistic Infections (CROI); February 19-22, 2023; Seattle, WA, USA."},{"key":"e_1_3_4_20_2","doi-asserted-by":"publisher","DOI":"10.1016\/S2352-3018(24)00030-4"},{"key":"e_1_3_4_21_2","doi-asserted-by":"publisher","DOI":"10.1016\/S2352-3018(24)00031-6"},{"key":"e_1_3_4_22_2","doi-asserted-by":"publisher","DOI":"10.1093\/infdis\/jiaf222:jiaf222"},{"key":"e_1_3_4_23_2","volume-title":"19th European AIDS Conference (EACS); October 18-21, 2023; Warsaw, Poland","author":"Lebron JA","unstructured":"Lebron JA, Sobol Z, Barnum J, Diamond TL, Ma D, Bhatt B, et al.. Investigational studies to understand the decreases in lymphocytes seen clinically with islatravir (ISL) and enabling the initiation of new clinical trials. 19th European AIDS Conference (EACS); October 18-21, 2023; Warsaw, Poland. 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