1257: Assessing the Effectiveness of Tocilizumab in Giant Cell Arteritis by PET: Multicenter Study of 101 Patients of Clinical Practice

Julio Sánchez-Martín¹, Javier Loricera¹, Santos Castañeda², Clara Moriano³, F. Javier Narváez⁴, Vicente Aldasoro⁵, Olga Maiz⁶, Rafael Melero⁷, Juan Ignacio Villa Blanco⁸, Paloma Vela-Casampere⁹, Susana Romero Yuste¹⁰, José Luis Callejas¹¹, Eugenio De Miguel¹², Eva Galíndez-Agirregoikoa¹³, Francisca Sivera¹⁴, Jesus Fernandez¹⁵, Carles Galisteo¹⁶, Ivan Ferraz Amaro¹⁷, Lara Sánchez-Bilbao¹, Monica Calderon-Goercke¹⁸, Miguel Ángel González-Gay¹⁹ and Ricardo Blanco²⁰, ¹Hospital Universitario Marqués de Valdecilla, Santander, Spain, ²Division of Rheumatology, Hospital Universitario de La Princesa, IIS-Princesa, Madrid, Spain, ³Complejo Asistencial Universitario de León, León, Spain, ⁴Rheumatology Department, Hospital Universitario de Bellvitge, Barcelona, Spain, ⁵Hospital Universitario de Navarra, Pamplona, Spain, ⁶Hospital Universitario de Donostia, San Sebastián, Spain, ⁷Complexo Hospitalario Universitario de Vigo, Vigo, Spain, ⁸Sierrallana Hospital, Torrelavega, Spain, ⁹Hospital General Universitario Alicante, Alicante, Spain, ¹⁰Complexo Hospitalario Universitario, Pontevedra, Spain, ¹¹Hospital San Cecilio, Granada, Spain, ¹²Hospital Universitario La Paz, Madrid, Spain, ¹³Basurto University Hospital, Bilbao, Spain, ¹⁴Hospital Universitario de Elda, San Vicente del Raspeig, Spain, ¹⁵Hospital de La Coruña, La Coruña, Spain, ¹⁶Hospital Parc Tauli,, Sabadel, Spain, ¹⁷Division of Rheumatology. Hospital Universitario de Canarias. Spain., Santa Cruz de Tenerife, Spain, ¹⁸Hospital de Sierrallana, Torrelavega, Spain, ¹⁹Department of Medicine and Psychiatry, Universidad de Cantabria; Rheumatology Division, Hospital Universitario Marqués de Valdecilla; Research group on genetic epidemiology and atherosclerosis in systemic diseases and in metabolic diseases of the musculoskeletal system, IDIVAL, Santander, Spain. Cardiovascular Pathophysiology and Genomics Research Unit, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa, ²⁰Hospital Universitario Marqués de Valdecilla, IDIVAL, Santander, Spain

Background/Purpose: Positron emission tomography (PET) is one of the tools available for the diagnosis of extracranial large-vessel vasculitis (1-5). Tocilizumab (TCZ) has shown efficacy in large-vessel vasculitis (LVV) including GCA. However, the improvement objectified by imaging techniques after TCZ therapy in extracranial GCA patients is controversial.

The purpose of this study is to assess the effectiveness of TCZ improving the wall vessel inflammation by PET in GCA patients with large-vessel involvement.

Methods: Observational, multicenter study of 101 GCA patients treated with TCZ. GCA was diagnosed according to: a) ACR criteria, and/or b) biopsy of temporal artery, and/or c) presence of signs of vessel wall inflammation by PET, defined by the presence of vascular wall uptake of Fluorodeoxyglucose (FDG). Patients were divided into two subgroups: a) with, and b) without signs of improvement (partial or total) in the follow-up PET.

Results: We studied 101 patients (74 women/27 men; mean age 69.7±9.3 years). Main clinical features of GCA with and without PET improvement are shown in TABLE. The group of patients which experienced PET improvement was older and was receiving higher doses of corticosteroids at TCZ onset.

Conclusion: TCZ seems to be effective controlling GCA including vascular involvement detected by PET. However, the improvement observed by PET is most often partial, and rarely complete.

References:

1. Loricera J, et al. Rev Esp Med Nucl Imagen Mol. 2015; 34: 372-7. PMID: 26272121
2. Loricera J, et al. Clin Exp Rheumatol. 2015; 33: S19-31. PMID: 25437450
3. Prieto-Peña D, et al. Ther Adv Musculoskelet Dis. 2021; 13: 1759720X211020917. PMID: 34211589
4. Martínez-Rodríguez I, et al. Semin Arthritis Rheum. 2018; 47: 530-537. PMID: 28967430
5. Prieto-Peña D, et al. Semin Arthritis Rheum. 2019; 48: 720-727. PMID: 29903537

Main features of 101 GCA patients treated with tocilizumab and with presence of signs of vessel wall inflammation by PET.

Improvement by PET according to the time of the test.
Disclosures: J. Sánchez-Martín, None; J. Loricera, None; S. Castañeda, Roche; C. Moriano, None; F. Narváez, None; V. Aldasoro, None; O. Maiz, None; R. Melero, None; J. Villa Blanco, None; P. Vela-Casampere, None; S. Romero Yuste, Pfizer, Lilly, AbbVie, Biogen, Sanofi; J. Callejas, None; E. De Miguel, None; E. Galíndez-Agirregoikoa, None; F. Sivera, None; J. Fernandez, None; C. Galisteo, None; I. Ferraz Amaro, AbbVie/Abbott, Merck/MSD, Janssen, Roche, AbbVie/Abbott, Pfizer, Roche, Amgen, Celgene, Merck/MSD; L. Sánchez-Bilbao, Eli Lilly; M. Calderon-Goercke, None; M. González-Gay, AbbVie/Abbott, Merck/MSD, Janssen, Roche, AbbVie/Abbott, Roche, Sanofi, Eli Lilly, Celgene, Sobi, Merck/MSD; R. Blanco, Eli Lilly, Pfizer, Roche, Janssen, MSD, AbbVie, Amgen, AstraZeneca, Bristol Myers Squibb, Galapagos, Novartis, Sanofi.