{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,28]],"date-time":"2026-03-28T06:46:31Z","timestamp":1774680391002,"version":"3.50.1"},"reference-count":60,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T00:00:00Z","timestamp":1774483200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biologics"],"abstract":"<jats:p>Background\/Objectives: The continuous emergence of immune-evasive SARS-CoV-2 variants underscores the need for adaptable and accessible therapeutics that complement vaccination. Single-domain antibodies (sdAbs) offer advantages in size, stability, and production costs compared to conventional monoclonal antibodies, but their clinical utility is limited by rapid clearance. This study aimed to develop a rabbit-derived sdAb with broad SARS-CoV-2 neutralization capacity and improved pharmacokinetic properties. Methods: A rabbit-derived variable light-chain (VL) sdAb library was constructed and subjected to phage display selection to identify high-affinity binders. Candidate sdAbs were characterized for cross-variant binding and neutralization. The lead sdAb, B3, was fused to the albumin-binding domain (ABD) of the Streptococcus zooepidemicus Zag protein to enhance in vivo half-life. Expression, albumin-binding capacity, and in vitro neutralization were assessed, followed by biodistribution studies in mice. Results: The selected sdAb, B3, showed strong binding and cross-variant neutralization against multiple SARS-CoV-2 lineages, including Delta and Omicron. Fusion to ABD(Zag) preserved neutralization potency, increased expression yields ~5-fold, and enabled cross-species albumin binding. In vivo, B3-ABD(Zag) exhibited markedly extended blood retention, showing a 21.2-fold increase at 24 h post-injection (5.30 vs. 0.25% I.A.\/g), and reduced renal uptake by 40% compared with unmodified B3. Conclusions: Rabbit-derived VL sdAbs fused to ABD(Zag) provide a promising platform for next-generation SARS-CoV-2 biologics. The enhanced pharmacokinetic profile of B3-ABD(Zag) supports its potential as a scalable therapeutic modality and highlights the broader utility of this approach for future emerging infectious threats.<\/jats:p>","DOI":"10.3390\/biologics6020010","type":"journal-article","created":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T13:50:15Z","timestamp":1774533015000},"page":"10","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Rabbit-Derived Single-Domain Antibody Fused to the Streptococcus zooepidemicus Zag Protein Engineered for SARS-CoV-2 Neutralization and Extended Half-Life"],"prefix":"10.3390","volume":"6","author":[{"given":"Isa","family":"Moutinho","sequence":"first","affiliation":[{"name":"Center for Interdisciplinary Research in Animal Health (CIISA), Faculty of Veterinary Medicine, University of Lisbon, 1300-477 Lisbon, Portugal"},{"name":"Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 1300-477 Lisbon, Portugal"}]},{"given":"Rafaela","family":"Marimon","sequence":"additional","affiliation":[{"name":"Center for Interdisciplinary Research in Animal Health (CIISA), Faculty of Veterinary Medicine, University of Lisbon, 1300-477 Lisbon, Portugal"},{"name":"Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 1300-477 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3665-9571","authenticated-orcid":false,"given":"R\u00faben D. M.","family":"Silva","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares and Departamento de Engenharia e Ci\u00eancias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Estrada Nacional 10, 2695-066 Bobadela, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2119-8293","authenticated-orcid":false,"given":"C\u00e9lia","family":"Fernandes","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares and Departamento de Engenharia e Ci\u00eancias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Estrada Nacional 10, 2695-066 Bobadela, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7186-2060","authenticated-orcid":false,"given":"Lurdes","family":"Gano","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares and Departamento de Engenharia e Ci\u00eancias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Estrada Nacional 10, 2695-066 Bobadela, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7847-4906","authenticated-orcid":false,"given":"Jo\u00e3o D. G.","family":"Correia","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares and Departamento de Engenharia e Ci\u00eancias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Estrada Nacional 10, 2695-066 Bobadela, Portugal"}]},{"given":"Jo\u00e3o","family":"Gon\u00e7alves","sequence":"additional","affiliation":[{"name":"Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, University of Lisbon, 1649-003 Lisbon, Portugal"}]},{"given":"Lu\u00eds","family":"Tavares","sequence":"additional","affiliation":[{"name":"Center for Interdisciplinary Research in Animal Health (CIISA), Faculty of Veterinary Medicine, University of Lisbon, 1300-477 Lisbon, Portugal"},{"name":"Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 1300-477 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3821-419X","authenticated-orcid":false,"given":"Frederico","family":"Aires-da-Silva","sequence":"additional","affiliation":[{"name":"Center for Interdisciplinary Research in Animal Health (CIISA), Faculty of Veterinary Medicine, University of Lisbon, 1300-477 Lisbon, Portugal"},{"name":"Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 1300-477 Lisbon, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"106054","DOI":"10.1016\/j.ijantimicag.2020.106054","article-title":"Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2): A Global Pandemic and Treatment Strategies","volume":"56","author":"Sharma","year":"2020","journal-title":"Int. J. Antimicrob. Agents"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"110","DOI":"10.1136\/postgradmedj-2020-138386","article-title":"SARS-CoV-2 and the Pandemic of COVID-19","volume":"97","author":"Adil","year":"2020","journal-title":"Postgrad. Med. J."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"105924","DOI":"10.1016\/j.ijantimicag.2020.105924","article-title":"Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and Coronavirus Disease-2019 (COVID-19): The Epidemic and the Challenges","volume":"55","author":"Lai","year":"2020","journal-title":"Int. J. Antimicrob. Agents"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"e193","DOI":"10.1016\/S1473-3099(25)00079-9","article-title":"Virological Characteristics of the SARS-CoV-2 LP.8.1 Variant","volume":"25","author":"Chen","year":"2025","journal-title":"Lancet Infect. Dis."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"e443","DOI":"10.1016\/S1473-3099(25)00356-1","article-title":"Virological Characteristics of the SARS-CoV-2 NB.1.8.1 Variant","volume":"25","author":"Uriu","year":"2025","journal-title":"Lancet Infect. Dis."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"e374","DOI":"10.1016\/S1473-3099(25)00308-1","article-title":"Antigenic and Virological Characteristics of SARS-CoV-2 Variants BA.3.2, XFG, and NB.1.8.1","volume":"25","author":"Guo","year":"2025","journal-title":"Lancet Infect. Dis."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Saha, A., Ghosh Roy, S., Dwivedi, R., Tripathi, P., Kumar, K., Nambiar, S.M., and Pathak, R. (2025). Beyond the Pandemic Era: Recent Advances and Efficacy of SARS-CoV-2 Vaccines Against Emerging Variants of Concern. Vaccines, 13.","DOI":"10.3390\/vaccines13040424"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"101349","DOI":"10.1016\/j.coviro.2023.101349","article-title":"Antigenic Evolution of SARS Coronavirus 2","volume":"62","author":"Mykytyn","year":"2023","journal-title":"Curr. Opin. Virol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"179","DOI":"10.3233\/HAB-200441","article-title":"A Review of Monoclonal Antibodies in COVID-19: Role in Immunotherapy, Vaccine Development and Viral Detection","volume":"29","author":"Tabll","year":"2021","journal-title":"Hum. Antibodies"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Calder\u00f3n-Parra, J., Guisado-Vasco, P., Montejano-S\u00e1nchez, R., Estrada, V., Cuevas-Tasc\u00f3n, G., Aguareles, J., Arribas, J., Erro-Iribarren, M., Calvo-Salvador, M., and Fern\u00e1ndez-Cruz, A. (2023). Use of Monoclonal Antibodies in Immunocompromised Patients Hospitalized with Severe COVID-19: A Retrospective Multicenter Cohort. J. Clin. Med., 12.","DOI":"10.3390\/jcm12030864"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"228","DOI":"10.1016\/j.ijid.2023.06.021","article-title":"Monoclonal Antibodies as COVID-19 Prophylaxis Therapy in Immunocompromised Patient Populations","volume":"134","author":"Cowan","year":"2023","journal-title":"Int. J. Infect. Dis."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"894","DOI":"10.1016\/j.cell.2020.03.045","article-title":"Structural and Functional Basis of SARS-CoV-2 Entry by Using Human ACE2","volume":"181","author":"Wang","year":"2020","journal-title":"Cell"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"e311","DOI":"10.1016\/S1473-3099(22)00311-5","article-title":"Monoclonal Antibody Therapies against SARS-CoV-2","volume":"22","author":"Focosi","year":"2022","journal-title":"Lancet Infect. Dis."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"ofab268","DOI":"10.1093\/ofid\/ofab268","article-title":"Monoclonal Antibodies for Early Treatment of COVID-19 in a World of Evolving SARS-CoV-2 Mutations and Variants","volume":"8","author":"Pogue","year":"2021","journal-title":"Open Forum Infect. Dis."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"77","DOI":"10.4161\/mabs.2.1.10786","article-title":"Antibody Fragments","volume":"2","author":"Nelson","year":"2010","journal-title":"MAbs"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"eabh0319","DOI":"10.1126\/sciadv.abh0319","article-title":"Inhalable Nanobody (PiN-21) Prevents and Treats SARS-CoV-2 Infections in Syrian Hamsters at Ultra-Low Doses","volume":"7","author":"Nambulli","year":"2021","journal-title":"Sci. Adv."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1016\/j.pharmthera.2016.06.012","article-title":"Nanobodies\u00ae as Inhaled Biotherapeutics for Lung Diseases","volume":"169","author":"Allosery","year":"2017","journal-title":"Pharmacol. Ther."},{"key":"ref_18","first-page":"164","article-title":"A VHH Single-Domain Platform Enabling Discovery and Development of Monospecific Antibodies and Modular Neutralizing Bispecifics against SARS-CoV-2 Variants","volume":"7","author":"Yang","year":"2024","journal-title":"Antib. Ther."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Schl\u00f6r, A., Hirschberg, S., Amor, G.B., Meister, T.L., Arora, P., P\u00f6hlmann, S., Hoffmann, M., Pfaender, S., Eddin, O.K., and Kamhieh-Milz, J. (2022). SARS-CoV-2 Neutralizing Camelid Heavy-Chain-Only Antibodies as Powerful Tools for Diagnostic and Therapeutic Applications. Front. Immunol., 13.","DOI":"10.3389\/fimmu.2022.930975"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"278","DOI":"10.1038\/s41586-021-03676-z","article-title":"Nanobodies from Camelid Mice and Llamas Neutralize SARS-CoV-2 Variants","volume":"595","author":"Xu","year":"2021","journal-title":"Nature"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1111\/j.1600-065X.1998.tb01428.x","article-title":"Diversification of Rabbit VH Genes by Gene-Conversion-like and Hypermutation Mechanisms","volume":"162","author":"Mage","year":"1998","journal-title":"Immunol. Rev."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Makdasi, E., Levy, Y., Alcalay, R., Noy-Porat, T., Zahavy, E., Mechaly, A., Epstein, E., Peretz, E., Cohen, H., and Bar-On, L. (2021). Neutralizing Monoclonal Anti-SARS-CoV-2 Antibodies Isolated from Immunized Rabbits Define Novel Vulnerable Spike-Protein Epitope. Viruses, 13.","DOI":"10.3390\/v13040566"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1390","DOI":"10.1080\/22221751.2021.1942227","article-title":"Potent RBD-Specific Neutralizing Rabbit Monoclonal Antibodies Recognize Emerging SARS-CoV-2 Variants Elicited by DNA Prime-Protein Boost Vaccination","volume":"10","author":"Chen","year":"2021","journal-title":"Emerg. Microbes Infect."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"4837","DOI":"10.1038\/s41598-023-31568-x","article-title":"Rabbit Derived VL Single-Domains as Promising Scaffolds to Generate Antibody-Drug Conjugates","volume":"13","author":"Dias","year":"2023","journal-title":"Sci. Rep."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Andr\u00e9, A.S., Dias, J.N.R., Moutinho, I., Loureiro, J., Leonardo, A., Nogueira, S., Marimon, R.P., Bule, P., Correia, J., and Malh\u00f3, R. (2025). A New Treatment for Canine B-Cell Lymphoma Based on a Recombinant Single-Domain Antibody Immunotoxin Derived from Pseudomonas Aeruginosa Exotoxin A. Front. Vet. Sci., 12.","DOI":"10.3389\/fvets.2025.1491934"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Aguiar, S.I., Dias, J.N.R., Andr\u00e9, A.S., Silva, M.L., Martins, D., Carrapi\u00e7o, B., Castanho, M., Carri\u00e7o, J., Cavaco, M., and Gaspar, M.M. (2021). Highly Specific Blood-Brain Barrier Transmigrating Single-Domain Antibodies Selected by an In Vivo Phage Display Screening. Pharmaceutics, 13.","DOI":"10.3390\/pharmaceutics13101598"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"868","DOI":"10.1016\/j.copbio.2011.06.012","article-title":"Strategies for Extended Serum Half-Life of Protein Therapeutics","volume":"22","author":"Kontermann","year":"2011","journal-title":"Curr. Opin. Biotechnol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"215","DOI":"10.1007\/s40259-015-0133-6","article-title":"Fusion Proteins for Half-Life Extension of Biologics as a Strategy to Make Biobetters","volume":"29","author":"Strohl","year":"2015","journal-title":"BioDrugs"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/j.jbiotec.2017.05.017","article-title":"Albumin-Binding Domain from Streptococcus zooepidemicus Protein Zag as a Novel Strategy to Improve the Half-Life of Therapeutic Proteins","volume":"253","author":"Cantante","year":"2017","journal-title":"J. Biotechnol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"2678","DOI":"10.1038\/s41598-022-06549-1","article-title":"Characterization of the Canine CD20 as a Therapeutic Target for Comparative Passive Immunotherapy","volume":"12","author":"Dias","year":"2022","journal-title":"Sci. Rep."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"7978","DOI":"10.1073\/pnas.88.18.7978","article-title":"Assembly of Combinatorial Antibody Libraries on Phage Surfaces: The Gene III Site","volume":"88","author":"Barbas","year":"1991","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_32","unstructured":"(2010). Engineered Rabbit Antibody Variable Domains and Uses Thereof (Standard No. WO2008136694A9)."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1543922","DOI":"10.1155\/tbed\/1543922","article-title":"SARS-CoV-2 Seroprevalence in Indoor House Cats from the Lisbon Area During the COVID-19 Pandemic, 2019\u20132021","volume":"2024","author":"Moutinho","year":"2024","journal-title":"Transbound. Emerg. Dis."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Moutinho, I., Cardoso, S., Henriques, M., Gon\u00e7alves, J., Tavares, L., Gil, S., Nunes, T., and Aires-da-Silva, F. (2025). Seroprevalence of SARS-CoV-2 in Cats from COVID-19 Positive Households in the Lisbon Area. Front. Vet. Sci., 12.","DOI":"10.3389\/fvets.2025.1542397"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1146\/annurev-immunol-083122-043054","article-title":"SARS-CoV-2: The Interplay Between Evolution and Host Immunity","volume":"43","author":"Case","year":"2025","journal-title":"Annu. Rev. Immunol."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"e0075124","DOI":"10.1128\/mbio.00751-24","article-title":"Distinct Patterns of SARS-CoV-2 BA.2.87.1 and JN.1 Variants in Immune Evasion, Antigenicity, and Cell-Cell Fusion","volume":"15","author":"Li","year":"2024","journal-title":"mBio"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"126153","DOI":"10.1016\/j.vaccine.2024.07.054","article-title":"Impact of Vaccination on SARS-CoV-2 Evolution and Immune Escape Variants","volume":"42","author":"Jena","year":"2024","journal-title":"Vaccine"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Rotundo, S., Serapide, F., Berardelli, L., Gull\u00ec, S.P., Mongiardi, S., Tassone, M.T., Trecarichi, E.M., and Russo, A. (2025). Early Combined Therapy for COVID-19 in Immunocompromised Patients: A Promising Approach against Viral Persistence and Drug Resistance. BMC Infect. Dis., 25.","DOI":"10.1186\/s12879-025-11012-3"},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Razonable, R.R. (2024). Protecting the Vulnerable: Addressing the COVID-19 Care Needs of People with Compromised Immunity. Front. Immunol., 15.","DOI":"10.3389\/fimmu.2024.1397040"},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Berber, E., and Ross, T.M. (2024). Factors Predicting COVID-19 Vaccine Effectiveness and Longevity of Humoral Immune Responses. Vaccines, 12.","DOI":"10.3390\/vaccines12111284"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"238","DOI":"10.1056\/NEJMoa2035002","article-title":"REGN-COV2, a Neutralizing Antibody Cocktail, in Outpatients with COVID-19","volume":"384","author":"Weinreich","year":"2021","journal-title":"N. Engl. J. Med."},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Quiros-Roldan, E., Amadasi, S., Zanella, I., Degli Antoni, M., Storti, S., Tiecco, G., and Castelli, F. (2021). Monoclonal Antibodies against SARS-CoV-2: Current Scenario and Future Perspectives. Pharmaceuticals, 14.","DOI":"10.3390\/ph14121272"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"2451789","DOI":"10.1080\/19420862.2025.2451789","article-title":"Cost and Supply Considerations for Antibody Therapeutics","volume":"17","author":"Chen","year":"2025","journal-title":"mAbs"},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Wu, Y., Jiang, S., and Ying, T. (2017). Single-Domain Antibodies as Therapeutics against Human Viral Diseases. Front. Immunol., 8.","DOI":"10.3389\/fimmu.2017.01802"},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Swart, I.C., Van Gelder, W., De Haan, C.A.M., Bosch, B.-J., and Oliveira, S. (2024). Next Generation Single-Domain Antibodies against Respiratory Zoonotic RNA Viruses. Front. Mol. Biosci., 11.","DOI":"10.3389\/fmolb.2024.1389548"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"e305","DOI":"10.1038\/emm.2017.23","article-title":"From Rabbit Antibody Repertoires to Rabbit Monoclonal Antibodies","volume":"49","author":"Weber","year":"2017","journal-title":"Exp. Mol. Med."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"628","DOI":"10.4161\/mabs.28059","article-title":"The Functional Repertoire of Rabbit Antibodies and Antibody Discovery via Next-Generation Sequencing","volume":"6","author":"Kodangattil","year":"2014","journal-title":"mAbs"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"364","DOI":"10.1038\/s42003-023-04759-5","article-title":"Mechanism of a Rabbit Monoclonal Antibody Broadly Neutralizing SARS-CoV-2 Variants","volume":"6","author":"Guo","year":"2023","journal-title":"Commun. Biol."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1016\/j.bbrc.2023.04.002","article-title":"Mechanism of an RBM-Targeted Rabbit Monoclonal Antibody 9H1 Neutralizing SARS-CoV-2","volume":"660","author":"Chu","year":"2023","journal-title":"Biochem. Biophys. Res. Commun."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"112014","DOI":"10.1016\/j.celrep.2023.112014","article-title":"Bivalent Intra-Spike Binding Provides Durability against Emergent Omicron Lineages: Results from a Global Consortium","volume":"42","author":"Callaway","year":"2023","journal-title":"Cell Rep."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1186\/s12951-021-00768-w","article-title":"Development of Multivalent Nanobodies Blocking SARS-CoV-2 Infection by Targeting RBD of Spike Protein","volume":"19","author":"Lu","year":"2021","journal-title":"J. Nanobiotechnol."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"2100099","DOI":"10.1002\/adtp.202100099","article-title":"Engineered Multivalent Nanobodies Potently and Broadly Neutralize SARS-CoV-2 Variants","volume":"4","author":"Zupancic","year":"2021","journal-title":"Adv. Ther."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"105259","DOI":"10.1016\/j.isci.2022.105259","article-title":"Biparatopic Nanobodies Targeting the Receptor Binding Domain Efficiently Neutralize SARS-CoV-2","volume":"25","author":"Pymm","year":"2022","journal-title":"iScience"},{"key":"ref_54","doi-asserted-by":"crossref","unstructured":"Harmsen, M.M., Ackerschott, B., and de Smit, H. (2024). Serum Immunoglobulin or Albumin Binding Single-Domain Antibodies That Enable Tailored Half-Life Extension of Biologics in Multiple Animal Species. Front. Immunol., 15.","DOI":"10.3389\/fimmu.2024.1346328"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"1015","DOI":"10.1002\/emmm.201201379","article-title":"Fc-Fusion Proteins: New Developments and Future Perspectives","volume":"4","author":"Czajkowsky","year":"2012","journal-title":"EMBO Mol. Med."},{"key":"ref_56","doi-asserted-by":"crossref","unstructured":"Li, C., Li, T., Tian, X., An, W., Wang, Z., Han, B., Tao, H., Wang, J., and Wang, X. (2024). Research Progress on the PEGylation of Therapeutic Proteins and Peptides (TPPs). Front. Pharmacol., 15.","DOI":"10.3389\/fphar.2024.1353626"},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"795","DOI":"10.1007\/s40259-024-00684-z","article-title":"Adverse Impacts of PEGylated Protein Therapeutics: A Targeted Literature Review","volume":"38","author":"Lee","year":"2024","journal-title":"BioDrugs"},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"235","DOI":"10.1042\/BST20241419","article-title":"Advances in Nanobody Multimerization and Multispecificity: From in Vivo Assembly to in Vitro Production","volume":"53","author":"Chen","year":"2025","journal-title":"Biochem. Soc. Trans."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"1752529","DOI":"10.1080\/19420862.2020.1752529","article-title":"Multimeric Antibodies with Increased Valency Surpassing Functional Affinity and Potency Thresholds Using Novel Formats","volume":"12","author":"Miller","year":"2020","journal-title":"mAbs"},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"1494","DOI":"10.1021\/acs.bioconjchem.2c00220","article-title":"Generation of Multivalent Nanobody-Based Proteins with Improved Neutralization of Long \u03b1-Neurotoxins from Elapid Snakes","volume":"33","author":"Wade","year":"2022","journal-title":"Bioconjug. Chem."}],"container-title":["Biologics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2673-8449\/6\/2\/10\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,28]],"date-time":"2026-03-28T05:22:45Z","timestamp":1774675365000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2673-8449\/6\/2\/10"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3,26]]},"references-count":60,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["biologics6020010"],"URL":"https:\/\/doi.org\/10.3390\/biologics6020010","relation":{},"ISSN":["2673-8449"],"issn-type":[{"value":"2673-8449","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,3,26]]}}}