Rational design of anti-GITR-based combination immunotherapy.
Nat Med
; 25(5): 759-766, 2019 05.
Article
em En
| MEDLINE
| ID: mdl-31036879
ABSTRACT
Modulating T cell homeostatic mechanisms with checkpoint blockade can efficiently promote endogenous anti-tumor T cell responses1-11. However, many patients still do not benefit from checkpoint blockade12, highlighting the need for targeting of alternative immune pathways13. Glucocorticoid-induced tumor necrosis factor receptor-related protein (GITR) is an attractive target for immunotherapy, owing to its capacity to promote effector T cell (Teff) functions14,15 and hamper regulatory T cell (Treg) suppression16-20. On the basis of the potent preclinical anti-tumor activity of agonist anti-GITR antibodies, reported by us and others16,21,22, we initiated the first in-human phase 1 trial of GITR agonism with the anti-GITR antibody TRX518 ( NCT01239134 ). Here, we report the safety profile and immune effects of TRX518 monotherapy in patients with advanced cancer and provide mechanistic preclinical evidence to rationally combine GITR agonism with checkpoint blockade in future clinical trials. We demonstrate that TRX518 reduces circulating and intratumoral Treg cells to similar extents, providing an easily assessable biomarker of anti-GITR activity. Despite Treg reductions and increased TeffTreg ratios, substantial clinical responses were not seen. Similarly, in mice with advanced tumors, GITR agonism was not sufficient to activate cytolytic T cells due to persistent exhaustion. We demonstrate that T cell reinvigoration with PD-1 blockade can overcome resistance of advanced tumors to anti-GITR monotherapy. These findings led us to start investigating TRX518 with PD-1 pathway blockade in patients with advanced refractory tumors ( NCT02628574 ).
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Proteína Relacionada a TNFR Induzida por Glucocorticoide
/
Anticorpos Monoclonais Humanizados
/
Imunoterapia
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Nat Med
Assunto da revista:
BIOLOGIA MOLECULAR
/
MEDICINA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Estados Unidos