Differential binding of sarilumab and tocilizumab to IL-6Rα and effects of receptor occupancy on clinical parameters
We evaluated interleukin-6 (IL-6) receptor-α subunit (IL-6Rα) signaling inhibition with sarilumab and tocilizumab, the association between IL-6Rα receptor occupancy (RO) and C-reactive protein (CRP), and the potential clinical relevance of any differences. For this, we measured IL-6Rα binding and si...
| Autores: | , , , , , , , , , , , , , , |
|---|---|
| Tipo de recurso: | artículo |
| Estado: | Versión aceptada para publicación |
| Fecha de publicación: | 2020 |
| País: | España |
| Institución: | Universitat Pompeu Fabra |
| Repositorio: | Repositorio Digital de la UPF |
| OAI Identifier: | oai:repositori.upf.edu:10230/56325 |
| Acceso en línea: | http://hdl.handle.net/10230/56325 http://dx.doi.org/10.1002/jcph.1795 |
| Access Level: | acceso abierto |
| Palabra clave: | C-reactive protein Interleukin-6 Receptors Rheumatoid arthritis Sarilumab Tocilizumab |
| Sumario: | We evaluated interleukin-6 (IL-6) receptor-α subunit (IL-6Rα) signaling inhibition with sarilumab and tocilizumab, the association between IL-6Rα receptor occupancy (RO) and C-reactive protein (CRP), and the potential clinical relevance of any differences. For this, we measured IL-6Rα binding and signaling inhibition with sarilumab and tocilizumab in vitro, simulated soluble IL-6Rα RO over time for approved sarilumab subcutaneous (SC) and tocilizumab intravenous (IV) and SC doses, and assessed associations between calculated RO and CRP reduction, 28-joint Disease Activity Score based on CRP, and 20%/50%/70% improvement in American College of Rheumatology responses from clinical data. Sarilumab binds IL-6Rα in vitro with 15- to 22-fold higher affinity than tocilizumab, and inhibits IL-6-mediated classical and trans signaling via membrane-bound and soluble IL-6Rα. Sarilumab 200 and 150 mg SC every 2 weeks achieved >90% RO after first and second doses, respectively, maintained throughout the treatment period. At steady-state trough, RO was greater with sarilumab 200 mg (98%) and 150 mg SC every 2 weeks (94%), and tocilizumab 162 mg SC weekly (>99%) and 8 mg/kg IV every 4 weeks (99%), vs tocilizumab 162 mg SC every 2 weeks (84%) and 4 mg/kg IV every 4 weeks (60%). Higher RO was associated with greater CRP reduction and 28-joint Disease Activity Score based on CRP reduction, and more sarilumab patients achieving 20%/50%/70% improvement in American College of Rheumatology responses. The greatest reduction in CRP levels was observed with sarilumab (both doses) and tocilizumab 8 mg/kg IV every 4 weeks (reductions proportionally smaller with 4 mg/kg IV every 4 weeks). Higher IL-6Rα binding affinity translated into higher RO with sarilumab vs tocilizumab 4 mg/kg every 4 weeks or 162 mg every 2 weeks; tocilizumab required the higher dose or increased frequency to maintain the same degree of RO and CRP reduction. Higher RO was associated with clinical parameter improvements. |
|---|