AUSTRALIAN JOURNAL OF BIOMEDICAL RESEARCH
Review Article
Jan 13, 2026 74 71

Gene Editing Therapies for Sickle Cell Disease and β-Thalassemia: A Systematic Review of Clinical Outcomes and Safety

Chidinma Lorretta Gab-Obinna 1 * ,
Ikemefula Oriaku 2,
Obiageri Ihuarulam Okeoma 3,
Adepeju Kafayat Olowookere 4,
Enobong Edoabasi Obong 5,
Nwamaka Nneka Onyedum 6,
Jazuli Isyaku Bala 7
1 Biomedical Science Department Kingston University London, England, UK2 Department of Medical Laboratory Science, University of Nigeria, Enugu Campus, Nigeria3 Department of Medical Laboratory Science, Trinity University Yaba, Lagos, Nigeria4 Department of Nanoscience., University of North Carolina at Greensboro, Greensboro, NC, USA5 Department of Neurology, Washington University, Saint Louis, MO, USA6 Department of Haematology, Nnamdi Azikiwe University Teaching Hospital, Nnewi, Anambra State, Nigeria 7 Department of Hematology and Transfusion Medicine, Faculty of Clinical Sciences, Bayero University Kano, Aminu Kano Teaching Hospital Kano (AKTH), Kano, Nigeria* Corresponding Author
Australian Journal of Biomedical Research, 2(1), 2026, aubm012, https://doi.org/10.63946/aubiomed/17736
Publication date: Jan 13, 2026
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ABSTRACT

Background: Sickle cell disease (SCD) and transfusion-dependent β-thalassemia (TDT) remain major global health burdens. Ex vivo gene-editing therapies aim to achieve durable fetal hemoglobin (HbF) induction or direct mutation correction.
Methods: We systematically reviewed clinical studies of CRISPR-Cas9 or base-editing therapies for SCD and TDT (MEDLINE, EMBASE, Web of Science, ClinicalTrials.gov, conference proceedings; 2010–03 December 2025). Eleven studies (>170 treated patients) reporting post-infusion outcomes were included.
Results: All therapies produced robust, pancellular HbF (30–65%) and total hemoglobin in/near the normal range. In TDT (n > 100 evaluable), transfusion independence (≥12 months, Hb ≥9 g/dL) was achieved in 89–100% across platforms, sustained up to >4 years. In SCD (n > 60 evaluable), adjudicated vaso-occlusive crises were eliminated for ≥12 months in ≥97% of patients treated with exagamglogene autotemcel and 100% in smaller cohorts (EDIT-301, BEAM-101). No graft failures occurred. Serious adverse events and one death were attributable to busulfan conditioning, not editing. No therapy-related malignancies or confirmed harmful off-target edits have been reported, although follow-up remains limited (median ~18 months, longest >4 years).
Conclusion: Current evidence from phase 1–3 trials demonstrates that ex vivo gene editing can achieve functional cure for many patients with TDT and severe SCD. Conditioning-related toxicity, limited long-term safety data, and delivery complexity remain critical barriers to broader implementation.

KEYWORDS

Gene Editing CRISPR-Cas9 Base Editing Sickle Cell Disease Β-Thalassemia Fetal Hemoglobin Transfusion Independence Systematic Review

CITATION (Vancouver)

Gab-Obinna CL, Oriaku I, Okeoma OI, Olowookere AK, Obong EE, Onyedum NN, et al. Gene Editing Therapies for Sickle Cell Disease and β-Thalassemia: A Systematic Review of Clinical Outcomes and Safety. Australian Journal of Biomedical Research. 2026;2(1):aubm012. https://doi.org/10.63946/aubiomed/17736
APA
Gab-Obinna, C. L., Oriaku, I., Okeoma, O. I., Olowookere, A. K., Obong, E. E., Onyedum, N. N., & Bala, J. I. (2026). Gene Editing Therapies for Sickle Cell Disease and β-Thalassemia: A Systematic Review of Clinical Outcomes and Safety. Australian Journal of Biomedical Research, 2(1), aubm012. https://doi.org/10.63946/aubiomed/17736
Harvard
Gab-Obinna, C. L., Oriaku, I., Okeoma, O. I., Olowookere, A. K., Obong, E. E., Onyedum, N. N., and Bala, J. I. (2026). Gene Editing Therapies for Sickle Cell Disease and β-Thalassemia: A Systematic Review of Clinical Outcomes and Safety. Australian Journal of Biomedical Research, 2(1), aubm012. https://doi.org/10.63946/aubiomed/17736
AMA
Gab-Obinna CL, Oriaku I, Okeoma OI, et al. Gene Editing Therapies for Sickle Cell Disease and β-Thalassemia: A Systematic Review of Clinical Outcomes and Safety. Australian Journal of Biomedical Research. 2026;2(1), aubm012. https://doi.org/10.63946/aubiomed/17736
Chicago
Gab-Obinna, Chidinma Lorretta, Ikemefula Oriaku, Obiageri Ihuarulam Okeoma, Adepeju Kafayat Olowookere, Enobong Edoabasi Obong, Nwamaka Nneka Onyedum, and Jazuli Isyaku Bala. "Gene Editing Therapies for Sickle Cell Disease and β-Thalassemia: A Systematic Review of Clinical Outcomes and Safety". Australian Journal of Biomedical Research 2026 2 no. 1 (2026): aubm012. https://doi.org/10.63946/aubiomed/17736
MLA
Gab-Obinna, Chidinma Lorretta et al. "Gene Editing Therapies for Sickle Cell Disease and β-Thalassemia: A Systematic Review of Clinical Outcomes and Safety". Australian Journal of Biomedical Research, vol. 2, no. 1, 2026, aubm012. https://doi.org/10.63946/aubiomed/17736

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