A phase 2 clinical trial assessing the efficacy and safety of pembrolizumab and radiotherapy in patients with metastatic triple-negative breast cancer Journal Article
| Authors: | Ho, A. Y.; Barker, C. A.; Arnold, B. B.; Powell, S. N.; Hu, Z. I.; Gucalp, A.; Lebron-Zapata, L.; Wen, H. Y.; Kallman, C.; D'Agnolo, A.; Zhang, Z.; Flynn, J.; Dunn, S. A.; McArthur, H. L. |
| Article Title: | A phase 2 clinical trial assessing the efficacy and safety of pembrolizumab and radiotherapy in patients with metastatic triple-negative breast cancer |
| Abstract: | Background: The current study was conducted to evaluate the efficacy and safety of pembrolizumab-mediated programmed cell death protein 1 inhibition plus radiotherapy (RT) in patients with metastatic triple-negative breast cancer who were unselected for programmed death-ligand 1 expression. Methods: The current study was a single-arm, Simon 2-stage, phase 2 clinical trial that enrolled a total of 17 patients with a median age of 52 years (range, 37-73 years). An RT dose of 3000 centigrays (cGy) was delivered in 5 daily fractions. Pembrolizumab was administered intravenously at a dose of 200 mg within 3 days of the first RT fraction, and then every 3 weeks ± 3 days until disease progression. The median follow-up was 34.5 weeks (range, 2.1-108.3 weeks). The primary endpoint of the current study was the overall response rate (ORR) at week 13 in patients with unirradiated lesions measured using Response Evaluation Criteria in Solid Tumors (RECIST; version 1.1). Secondary endpoints included safety and progression-free survival. Exploratory objectives were to identify biomarkers predictive of ORR and progression-free survival. Results: The ORR for the entire cohort was 17.6% (3 of 17 patients; 95% CI, 4.7%-44.2%), with 3 complete responses (CRs), 1 case of stable disease, and 13 cases of progressive disease. Eight patients died prior to week 13 due to disease progression. Among the 9 women assessed using RECIST version 1.1 at week 13, 3 (33%) achieved a CR, with a 100% reduction in tumor volume outside of the irradiated portal. The CRs were durable for 18 weeks, 20 weeks, and 108 weeks, respectively. The most common grade 1 to 2 toxicity (assessed according to the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0) was dermatitis (29%). Four grade 3 adverse events were attributed to pembrolizumab: fatigue, lymphopenia, and infection. No were no grade 4 adverse events or treatment-related deaths reported. Conclusions: The combination of pembrolizumab and RT was found to be safe and demonstrated encouraging activity in patients with poor-prognosis, metastatic, triple-negative breast cancer who were unselected for programmed death-ligand 1 expression. Larger clinical trials of checkpoint blockade plus RT with predictive biomarkers of response are needed. © 2019 American Cancer Society |
| Keywords: | immunotherapy; metastatic; checkpoint blockade; radiotherapy (rt); triple-negative breast cancer (tnbc) |
| Journal Title: | Cancer |
| Volume: | 126 |
| Issue: | 4 |
| ISSN: | 0008-543X |
| Publisher: | Wiley Blackwell |
| Date Published: | 2020-02-15 |
| Start Page: | 850 |
| End Page: | 860 |
| Language: | English |
| DOI: | 10.1002/cncr.32599 |
| PUBMED: | 31747077 |
| PROVIDER: | scopus |
| DOI/URL: | |
| Notes: | Article -- Export Date: 3 February 2020 -- Source: Scopus |
Altmetric
Citation Impact
BMJ Impact Analytics
MSK Authors
Related MSK Work