Tsuchiya-Kawano Y, Shiraishi Y, Kiyomi F, et al. - For the first time ever in a prospective study, the emphasis is placed on the intracranial response to immune checkpoint inhibitor (ICI) therapy combined with platinum-based chemotherapy in cases with untreated brain metastases secondary to non-small cell lung cancer (NSCLC). This regimen could potentially serve as a new treatment option for such individuals only if the study shows intracranial efficacy for this patient population.

• Brain metastases occur in approximately 20% of patients with advanced NSCLC, and are associated with poor prognosis.

• The impact of ICI therapy combined with platinum-based chemotherapy on untreated brain metastases derived from NSCLC, was investigated.

• Participants include patients (20 years of age or older) with chemotherapy-naïve advanced NSCLC and at least one brain metastasis ≥ 5 mm in size that has not been previously treated.

• Patients (30 patients over 2.5 years at 27 oncology facilities in Japan) undergo nivolumab plus ipilimumab intravenously combined with histology-based platinum doublet chemotherapy (two cycles).

• Intracranial response rate, the primary endpoint, was assessed by modified Response Evaluation Criteria in Solid Tumors for brain metastases of ≥ 5 mm as target lesions.

• An increased treatment efficacy for brain metastases secondary to NSCLC is expected to be conferred by the addition of ipilimumab, an antibody to cytotoxic T lymphocyte antigen–4, to a programmed cell death–1–targeting antibody.