{"id":54594,"date":"2026-08-30T23:09:40","date_gmt":"2026-08-30T23:09:40","guid":{"rendered":"https:\/\/i-base.info\/htb\/?p=54594"},"modified":"2026-08-30T23:15:31","modified_gmt":"2026-08-30T23:15:31","slug":"macaque-study-eradicates-simian-hiv-shiv-with-combination-treatment-in-very-early-infection","status":"publish","type":"post","link":"https:\/\/i-base.info\/htb\/54594","title":{"rendered":"Macaque study eradicates simian HIV (SHIV) with combination treatment in very early infection"},"content":{"rendered":"

Simon Collins, HIV i-Base<\/strong><\/p>\n

A exciting study published in the journal Nature Microbiology tentatively reports potentially curing SHIV-infected young macaques following very early treatment with a combination of immune-based therapies plus a short course of ART. [1]<\/strong><\/p>\n

These findings are remarkable results because the animals all had confirmed SHIV infection with high viral load following high dose inoculation and had no detectable infection more than 18 months after stopping ART.<\/p>\n

The intervention involved a complex treatment combination initiated during a very short window period after infection, but these circumstances do reflect a real-world need when viral load tests confirm infection that would otherwise require lifelong treatment.<\/p>\n

The paper by Jonah B Sacha from Oregon Health & Science University and colleagues was published in Nature Microbiology and the study involved various treatments in 55 animals, mainly in groups of 6-8 and including a control group of untreated animals. The infant animals were all aged 1 month when orally infected with a single high dose of a highly pathogenic strain of SHIV, to mimic peripartum human infection during very late pregnancy, or during or shortly after birth.<\/p>\n

The effective combination that prevented both reservoir seeding and post-treatment viral rebound included two env-targetting bNAbs (VRC07-523LS and PGT121), a CCR5-targetting bNAb (leronlimab), and daily ART\u00a0(TDF\/FTC\/DTG), all started at 72 hours post-infection. VRC07-523LS and PGT121 were given as a single infusion, leronlimab was given by weekly subcutaneous injections for six weeks at a higher dose and three weeks at a lower dose, and ART was given daily for 27 weeks and then stopped (when washout of bNAbs and leronlimab was confirmed).<\/p>\n

None of these treatments was effective as monotherapy or in dual combinations in earlier stages of the research or in comparison groups. Even though some interventions reduced reservoir size, none prevented it from being established. Two untreated control animals experienced rapid viraemia to >10 million c\/mL within two weeks of infection. Two other animals given only bNAbs and ART, had viral rebound after ART was stopped (both HIV RNA and HIV DNA), at weeks 4 and 7 respectively. Interestingly, and not discussed in the paper, both animals then controlled viraemia at detectable but low levels <1,000 c\/mL out to week 60, perhaps showing a vaccinal effect from the bNAbs.<\/p>\n

By comparison, all eight animals in the triple combination group maintained undetectable viral load for six months after ART was stopped. All eight animals had previously had high levels of viraemia before treatment but cell-associated viral DNA wasn\u2019t detected in PBMCs or tissue samples in any animal throughout follow up, suggesting establishing the viral reservoir was prevented. No Gag-specific CD8+ T cells were found in any of the eight animals. Finally, after animals were euthanised at week 84, extensive sampling found no evidence of either intact nor defective virus.<\/p>\n

Although limitations in these results include perhaps needing more extensive tissue sampling and the duration of response was limited to 84 weeks after infection, the results were consistent for all animals receiving the combination treatment.<\/p>\n

The authors comment that these apparent cures appeared more related to preventing the viral reservoir rather than being immune mediated, but also that they cannot explain the mechanism responsible for their results.<\/p>\n

Reference<\/p>\n

Sacha JB et al. Combination therapy with broadly neutralizing antibodies, antiretroviral therapy and CCR5 blockade limits viral reservoir seeding in infant macaque model of HIV.\u00a0Nat Microbiol\u00a0(2026).
\nhttps:\/\/doi.org\/10.1038\/s41564-026-02444-x<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

Simon Collins, HIV i-Base A exciting study published in the journal Nature Microbiology tentatively reports potentially curing SHIV-infected young macaques following very early treatment with a combination of immune-based therapies plus a short course of ART. [1] These findings are …<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[20],"tags":[],"class_list":["post-54594","post","type-post","status-publish","format-standard","hentry","category-cure-research"],"_links":{"self":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/54594","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/comments?post=54594"}],"version-history":[{"count":3,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/54594\/revisions"}],"predecessor-version":[{"id":54597,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/54594\/revisions\/54597"}],"wp:attachment":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/media?parent=54594"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/categories?post=54594"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/tags?post=54594"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}