A French national real-world survey of people with multi-resistant HIV-1 viruses receiving an antiretroviral regimen including fostemsavir or ibalizumab

Abstract Background Attachment inhibitor fostemsavir (FTR) and post-attachment inhibitor ibalizumab (IBA), are used in highly treatment-experienced people with HIV-1 (PWH) harboring multidrug-resistant viruses, and real-world data remain limited. We describe population characteristics and pharmaco-virological outcomes of PWH initiating FTR- or IBA-based regimens. Methods We conducted a French retrospective observational study within the ANRS|MIE virology&pharmacology network. Virological failure (VF) was defined as two consecutive plasma viral loads (VL) ≥50 c/mL; non-virological response as a VL decrease <1 log10 c/mL or failure to achieve virological suppression. Results Among 70 PWH receiving FTR-based treatment, 50% were virologically-suppressed at initiation; median VL among viremic individuals was 3.6 log10 c/mL. Resistance to at least two ARVs was observed in 96%, 94%, 74%, and 64% of participants for NRTI, NNRTI, PI, and INSTI classes, respectively. Genotypic susceptibility score (GSS) was ≤1 in 47%, and median follow-up was 20 months. Eight VFs and eight non-virological responses occurred. At failure, emergence of FTR resistance-associated mutations occurred in one case. Suboptimal temsavir concentrations were observed in 2/8 participants in failure. Eleven viremic PWH initiated IBA-based treatment, GSS was ≤1 in four, and median follow-up was 7 months, with five VF and two non-virological responses. One new resistance mutation (N74D, capsid) was detected at VF; suboptimal plasma concentrations of oral ARV were observed in 3/5 participants. Conclusions PWH receiving FTR or IBA had extensive multidrug-resistance and limited therapeutic options. Virological success was achieved in 63% and 36% of viremic PWH initiating FTR- and IBA-based regimens, respectively, and maintained in 91% of virologically-suppressed PWH starting FTR-based regimen.

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Publication Details

Journal
Open Forum Infectious Diseases
Published
2026-08-14
DOI
https://doi.org/10.1093/ofid/ofag495
Primary Topic
HIV/AIDS drug development and treatment
Type
article
Field-Weighted Citation Impact
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article

A French national real-world survey of people with multi-resistant HIV-1 viruses receiving an antiretroviral regimen including fostemsavir or ibalizumab

Pauline Coulon, Caroline Proux, Clotilde Allavena, Constance Delaugerre et al.
Open Forum Infectious Diseases
HIV/AIDS drug development and treatment
article

A French national real-world survey of people with multi-resistant HIV-1 viruses receiving an antiretroviral regimen including fostemsavir or ibalizumab

Pauline Coulon, Caroline Proux, Clotilde Allavena, Constance Delaugerre, Vincent Cálvez, Véronique Avettand-Fènoël, Jade Ghosn, Gilbert Mchantaf, Élodie Alessandri-Gradt, Alice Moisan, Camille Vellas, Anne‐Geneviève Marcelin, Jean‐Michel Molina, Diane Descamps, Yoann Conan, Marc Wirden, Sidonie Lambert-Niclot, Enagnon Kazali Alidjinou, David Chirio, Valérie Pourcher, Pierre Delobel, Lynda Handala, Karl Stéfic, Gilles Peytavin, Kévin Alexandre, Mayda Rahi, Marie‐Laure Chaix, Antoine Bachelard, Stéphanie Raymond, Karine Lacombe, C. Rioux, Pascal Puglièse, Éric Cua, Anne De Monte, Audrey Rodallec, Charles Cazanave, Pantxika Bellecave, Adrien Lemaignen, Djeneba Fofana, Camille Tumiotto, Elisabeth Garnier, Bao Phung, Minh Lê, Estibalitz Lazaro, G Martin-Blondel, Justine Sourice, Laurent Hocqueloux, the Entry Inhibitors Observatory Study Group, Olivier Robineau, Fabrice Bonnet, Charlotte Charpentier
article en

Abstract

Abstract Background Attachment inhibitor fostemsavir (FTR) and post-attachment inhibitor ibalizumab (IBA), are used in highly treatment-experienced people with HIV-1 (PWH) harboring multidrug-resistant viruses, and real-world data remain limited. We describe population characteristics and pharmaco-virological outcomes of PWH initiating FTR- or IBA-based regimens. Methods We conducted a French retrospective observational study within the ANRS|MIE virology&pharmacology network. Virological failure (VF) was defined as two consecutive plasma viral loads (VL) ≥50 c/mL; non-virological response as a VL decrease <1 log10 c/mL or failure to achieve virological suppression. Results Among 70 PWH receiving FTR-based treatment, 50% were virologically-suppressed at initiation; median VL among viremic individuals was 3.6 log10 c/mL. Resistance to at least two ARVs was observed in 96%, 94%, 74%, and 64% of participants for NRTI, NNRTI, PI, and INSTI classes, respectively. Genotypic susceptibility score (GSS) was ≤1 in 47%, and median follow-up was 20 months. Eight VFs and eight non-virological responses occurred. At failure, emergence of FTR resistance-associated mutations occurred in one case. Suboptimal temsavir concentrations were observed in 2/8 participants in failure. Eleven viremic PWH initiated IBA-based treatment, GSS was ≤1 in four, and median follow-up was 7 months, with five VF and two non-virological responses. One new resistance mutation (N74D, capsid) was detected at VF; suboptimal plasma concentrations of oral ARV were observed in 3/5 participants. Conclusions PWH receiving FTR or IBA had extensive multidrug-resistance and limited therapeutic options. Virological success was achieved in 63% and 36% of viremic PWH initiating FTR- and IBA-based regimens, respectively, and maintained in 91% of virologically-suppressed PWH starting FTR-based regimen.

Open Forum Infectious Diseases
Université de Tours (FR), Université d'Orléans (FR), Centre National de la Recherche Scientifique (FR), Université de Bordeaux (FR), Inserm (FR), Université Paris Cité (FR), Université de Lille (FR), Centre Hospitalier Universitaire de Bordeaux (FR), Centre Hospitalier Universitaire de Nice (FR), Centre Hospitalier Universitaire de Nantes (FR), Sorbonne Université (FR), Centre Hospitalier Universitaire de Tours (FR), Assistance Publique – Hôpitaux de Paris (FR), Normandie Université (FR), Centre de Physiopathologie de Toulouse-Purpan (FR), Centre d'Investigation Clinique de Nantes (FR), Institut Pierre Louis d‘Épidémiologie et de Santé Publique (FR), Hôpital Purpan (FR), Hôpital Saint-Louis (FR), Centre hospitalier universitaire d'Orléans (FR), Hôpital Bichat-Claude-Bernard (FR), Institut Polytechnique de Bordeaux (FR), Université de Rouen Normandie (FR)
Styrelsen för Internationellt Utvecklingssamarbete, European Commission
Good health and well-being
Openalex Percentile: Top 10%
HIV/AIDS drug development and treatment
DOIOpen Access PDFOpenAlex
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