Østergaard Michael E, Carrer Michele, Anderson Brooke A, Afetian Megan, Bakooshli Mohsen A, Santos Jinro A, Klein Stephanie K, Capitanio Juliana, Freestone Graeme C, Tanowitz Michael, Galindo-Murillo Rodrigo, Gaus Hans J, Dwyer Chrissa A, Jackson Michaela, Jafar-Nejad Paymaan, Rigo Frank, Seth Punit P, Gaynor Katherine U, Stanway Steven J, Urbonas Liudvikas, St Denis Megan A, Pellegrino Simone, Bezerra Gustavo A, Rigby Michael, Gowans Ellen, Van Rietschoten Katerine, Beswick Paul, Chen Liuhong, Skynner Michael J, Swayze Eric E
Ionis Pharmaceuticals Inc., 2855 Gazelle Court, Carlsbad, CA 92010, United States.
Bicycle Therapeutics, Portway Building, Granta Park, Cambridge CB21 6GS, United Kingdom.
Nucleic Acids Res. 2025 Apr 10;53(7). doi: 10.1093/nar/gkaf270.
Improving the delivery of antisense oligonucleotides (ASOs) and small interfering RNAs (siRNAs) to skeletal and cardiac muscles remains a pivotal task toward the broader application of oligonucleotide therapeutics. The targeting of myofibers and cardiomyocytes via conjugation of ASOs and siRNAs to ligands that bind the human transferrin receptor 1 (TfR1) has gathered significant interest in recent years. However, the selection of ligands with low molecular weight and optimal biophysical and binding properties is crucial to maximize the potential of the TfR1 ligand-conjugated antisense (LICA) technology. Here, through effective combination of phage display and peptide medicinal chemistry, we identified and characterized a bicyclic peptide (Bicycle® molecule BCY17901), with a molecular weight of ∼2 kDa, that binds human TfR1 with high affinity and specificity. Conjugation to BCY17901 improved ASO and siRNA potency in skeletal and cardiac muscles of human TfR1 knock-in mice, after either intravenous or subcutaneous administration. Furthermore, single-nucleus RNA sequencing showed that conjugation to BCY17901 enhanced ASO activity in myonuclei of different muscle fiber types. Importantly, we demonstrated good translatability of our TfR1-targeting platform in skeletal and cardiac muscles of nonhuman primates. Our results offer great promise toward potential future applications of low-molecular-weight Bicycle LICA therapeutics for the treatment of diseases affecting skeletal muscle and heart.
提高反义寡核苷酸（ASO）和小干扰RNA（siRNA）向骨骼肌和心肌的递送效率，仍然是推动寡核苷酸疗法更广泛应用的关键任务。近年来，通过将ASO和siRNA与结合人转铁蛋白受体1（TfR1）的配体偶联来靶向肌纤维和心肌细胞，已引起了广泛关注。然而，选择具有低分子量以及最佳生物物理和结合特性的配体，对于最大化TfR1配体偶联反义（LICA）技术的潜力至关重要。在此，通过噬菌体展示和肽药物化学的有效结合，我们鉴定并表征了一种分子量约为2 kDa的双环肽（Bicycle®分子BCY17901），它能以高亲和力和特异性结合人TfR1。在静脉内或皮下给药后，与BCY17901偶联可提高ASO和siRNA在人TfR1基因敲入小鼠的骨骼肌和心肌中的效力。此外，单核RNA测序表明，与BCY17901偶联可增强ASO在不同肌纤维类型的肌核中的活性。重要的是，我们证明了我们的TfR1靶向平台在非人灵长类动物的骨骼肌和心肌中具有良好的可转化性。我们的结果为低分子量Bicycle LICA疗法未来潜在应用于治疗影响骨骼肌和心脏的疾病带来了巨大希望。
