Synapse - Phase II single-arm study of durvalumab and tremelimumab with concurrent radiotherapy in patients with mismatch repair-proficient metastatic colorectal cancer

Phase II single-arm study of durvalumab and tremelimumab with concurrent radiotherapy in patients with mismatch repair-proficient metastatic colorectal cancer Journal Article

Authors:	Segal, N. H.; Cercek, A.; Ku, G.; Wu, A. J.; Rimner, A.; Khalil, D. N.; Reidy-Lagunes, D.; Cuaron, J.; Yang, T. J.; Weiser, M. R.; Romesser, P. B.; Stadler, Z. K.; Varghese, A. M.; Ganesh, K.; Yaeger, R.; Connell, L. C.; Faleck, D.; Abou-Alfa, G. K.; McAuliffe, K. C.; Vaiskauskas, P.; Solter, M. L.; Ogle, M.; Adamow, M. J.; Holland, A.; Vedantam, P.; Wong, P.; Merghoub, T.; Vakiani, E.; Hollmann, T. J.; Juluru, K.; Chou, J. F.; Capanu, M.; Erinjeri, J.; Solomon, S.; Yamada, Y.; Kemeny, N.; Crane, C. H.; Saltz, L. B.
Article Title:	Phase II single-arm study of durvalumab and tremelimumab with concurrent radiotherapy in patients with mismatch repair-proficient metastatic colorectal cancer
Abstract:	PURPOSE: Immune checkpoint inhibition (ICI) alone is not active in mismatch repair-proficient (MMR-P) metastatic colorectal cancer (mCRC), nor does radiotherapy alone result in objective systemic benefit. However, combined radiotherapy plus ICI can induce systemic antitumor immunity in preclinical and clinical models. PATIENTS AND METHODS: In this single-center, phase II study, patients with chemotherapy-refractory MMR-P mCRC received durvalumab 1,500 mg plus tremelimumab 75 mg every 4 weeks plus radiotherapy. The primary endpoint was objective response rate (ORR) in nonirradiated lesions. Treatment and efficacy were correlated with peripheral immune cell profiles. RESULTS: We enrolled 24 patients, and report outcomes after a median follow-up of 21.8 (range: 15.9-26.3) months. The ORR was 8.3% (2 patients) [95% confidence interval (CI), 1.0-27.0]. The median progression-free survival was 1.8 (95% CI, 1.7-1.9) months, median overall survival was 11.4 (95% CI, 10.1-17.4) months. Twenty five percent of patients (n = 6) had treatment-related grade 3-4 adverse events. We observed increased circulating CD8+ T lymphocyte activation, differentiation, and proliferation in patients with objective response. CONCLUSIONS: This combination of radiotherapy plus ICI study did not meet the prespecified endpoint criteria to be considered worthwhile for further study. However, rare instances of systemic immune augmentation and regression in nonirradiated lesions were observed (an abscopal response). Combination durvalumab and tremelimumab plus radiotherapy is feasible in MMR-P mCRC with a manageable safety profile. Further studies of novel immunotherapy combinations, and identification of biomarkers predictive of abscopal response are warranted. ©2021 American Association for Cancer Research.
Journal Title:	Clinical Cancer Research
Volume:	27
Issue:	8
ISSN:	1078-0432
Publisher:	American Association for Cancer Research
Date Published:	2021-04-15
Start Page:	2200
End Page:	2208
Language:	English
DOI:	10.1158/1078-0432.Ccr-20-2474
PUBMED:	33504552
PROVIDER:	scopus
PMCID:	PMC8499477
DOI/URL:	https://www.scopus.com/inward/record.uri?eid=2-s2.0-85104326667&doi=10.1158%2f1078-0432.CCR-20-2474&partnerID=40&md5=6182435d0142b6ded163ba1edaee407f
Notes:	Article -- Export Date: 3 May 2021 -- Source: Scopus