medwireNews: Cabozantinib in combination with atezolizumab has “encouraging” antitumor activity, while cabozantinib alone has “modest” activity, in people who have received prior immune checkpoint inhibitor (ICI) treatment for advanced non-small-cell lung cancer (NSCLC), say trial investigators.
The findings from the multicohort phase 1b COSMIC-021 study were presented at the 2022 ASCO Annual Meeting in Chicago, Illinois, USA, by Joel Neal (Stanford Cancer Institute, Palo Alto, California, USA).
He explained that initial results from cohort 7 of the trial – which at that point included 30 ICI-treated patients with metastatic NSCLC – showed favorable outcomes with cabozantinib plus atezolizumab, warranting an expansion of the cohort.
In the current presentation, Neal reported on 81 participants of the expanded cohort 7 and 31 participants of cohort 20, all of whom had nonsquamous stage IV NSCLC lacking EGFR, ALK, ROS1, or BRAF V600E alterations for which they had received no more than two prior lines of systemic therapy, including one ICI.
Cohort 7 patients received oral cabozantinib 40 mg/day plus intravenous atezolizumab 1200 mg every 3 weeks, which achieved an objective response rate of 19% over a median follow-up of 24.7 months. All responses were partial and lasted for a median of 5.8 months. A further 62% of patients had stable disease, giving a disease control rate (DCR) of 80%.
The median progression-free survival (PFS) and overall survival (OS) times were 4.5 and 13.8 months, respectively.
Patients included in cohort 20 received cabozantinib alone at a daily dose of 60 mg and were followed up for a median of 21.5 months. The ORR in this cohort was “very low,” at 6%, and the DCR was 65%, reported Neal. The median duration of response was 10.6 months, while median PFS was 3.4 months and median OS was 9.4 months.
“Toxicities with both cabozantinib plus atezolizumab, and cabozantinib alone, were consistent with those previously reported,” said the presenter.
Treatment-emergent adverse events (TEAEs) of grade 3 or 4 occurred in 53% of patients in cohort 7 and 71% of those in cohort 20. Hypertension and asthenia were the most common events of this severity in cohort 7, each occurring in 6%, while hypertension was most common in cohort 20, at 23%, followed by asthenia and diarrhea, each in 10%.
There was one grade 5 TEAE in each cohort, a case of pneumonitis in cohort 7 and one of gastric ulcer hemorrhage in cohort 20.
In conclusion, Neal said that “we look forward to seeing” the results of “an ongoing randomized phase 2 clinical trial of cabozantinib plus nivolumab versus standard of care single-agent chemotherapy – the ECOG ACRIN 5191 study – as well as a phase 3 trial of cabozantinib plus atezolizumab versus docetaxel, the CONTACT-01 study,” in previously treated patients with NSCLC.
Discussant Christine Bestvina, from the University of Chicago Comprehensive Cancer Center, said that although the COSMIC-021 trial did not answer the question “is atezolizumab needed,” it showed “promising activity in an important area of unmet need.”
medwireNews is an independent medical news service provided by Springer Healthcare Ltd. © 2022 Springer Healthcare Ltd, part of the Springer Nature Group