Purpose: Malignant pleural mesothelioma (MPM) is a rare and aggressive malignancy with poor prognosis. Patients with MPM who do not respond to standard first-line chemotherapy have limited treatment options. We evaluated the efficacy and safety of nivolumab, an immune checkpoint inhibitor, for the treatment of advanced or metastatic MPM. Patients and Methods: Japanese patients with unresectable, advanced, or metastatic MPM resistant or intolerant to ≤2 regimens of chemotherapy and ≥1 measurable lesion(s) were enrolled. Patients received nivolumab 240 mg intravenously every 2 weeks until progressive disease or unacceptable toxicity. The primary endpoint was objective response rate by central assessment according to the Modified Response Evaluation Criteria in Solid Tumors. Adverse events (AEs) and treatment-related AEs (TRAEs) were evaluated. Results: Thirty-four patients were enrolled between July 2016 and October 2016. Median follow-up was 16.8 (range: 1.8–20.2) months. Ten (29%, 95% confidence interval, 16.8–46.2) patients showed a centrally assessed objective response. The objective response rates were 26% (7/27), 67% (2/3), and 25% (1/4) patients for epithelioid, sarcomatoid, and biphasic histologic subtypes, respectively. Median duration of response was 11.1 months with a 68% disease control rate. Median overall survival and progression-free survival were 17.3 and 6.1 months, respectively. The objective response rate was 40% with programmed death-ligand 1 expression ≥1% and 8% with <1%. Thirty-two patients (94%) experienced AEs and 26 (76%) experienced TRAEs. Conclusions: Nivolumab met the primary endpoint as second- or third-line treatment for patients with MPM and showed promising efficacy with manageable toxicity. See related commentary by Mansfield and Zauderer, p. 5438

BACKGROUND. The PD-1–blocking antibody nivolumab persists in patients several weeks after the last infusion. However, no study has systematically evaluated the maximum duration that the antibody persists on T cells or the association between this duration and residual therapeutic efficacy or potential adverse events. METHODS. To define the duration of binding and residual efficacy of nivolumab after discontinuation, we developed a simplified strategy for T cell monitoring and used it to analyze T cells from peripheral blood from 11 non–small cell lung cancer patients previously treated with nivolumab. To determine the suitability of our method for other applications, we compared transcriptome profiles between nivolumab-bound and nivolumab-unbound CD8 T cells. We also applied T cell monitoring in 2 nivolumab-treated patients who developed progressive lung tumors during long-term follow-up. RESULTS. Prolonged nivolumab binding was detected more than 20 weeks after the last infusion, regardless of the total number of nivolumab infusions (2–15 doses) or type of subsequent treatment, in 9 of the 11 cases in which long-term monitoring was possible. Ki-67 positivity, a proliferation marker, in T cells decreased in patients with progressive disease. Transcriptome profiling identified the signals regulating activation of nivolumab-bound T cells, which may contribute to nivolumab resistance. In 2 patients who restarted nivolumab, T cell proliferation markers exhibited the opposite trend and correlated with clinical response. CONCLUSIONS. Although only a few samples were analyzed, our strategy of monitoring both nivolumab binding and Ki-67 in T cells might help determine residual efficacy under various types of concurrent or subsequent treatment. TRIAL REGISTRATION. University Hospital Medical Information Network Clinical Trials Registry, UMIN000024623. FUNDING. This work was supported by Japan Society for the Promotion of Science KAKENHI (JP17K16045, JP18H05282, and JP15K09220), Japan Agency for Medical Research and Development (JP17cm0106310, JP18cm0106335 and JP18cm059042), and Core Research for Evolutional Science and Technology (JPMJCR16G2).

A ketogenic diet is expected to be an effective support therapy for patients with cancer, but the degree and duration of carbohydrate restriction are unclear. We performed a case series study of a new ketogenic diet regimen in patients with different types of stage IV cancer. Carbohydrates were restricted to 10 g/day during week one, 20 g/day from week two for three months, and 30 g/day thereafter. A total of 55 patients participated in the study, and data from 37 patients administered the ketogenic diet for three months were analyzed. No severe adverse events associated with the diet were observed. Total ketone bodies increased significantly, and both fasting blood sugar and insulin levels were suppressed significantly for three months after completion of the study. Five patients showed a partial response on Positron emission tomography–computed tomography (PET-CT) at three months. Three and seven patients showed complete and partial responses, respectively at one year. Median survival was 32.2 (maximum: 80.1) months, and the three-year survival rate was 44.5%. After three months on the ketogenic diet, the serum Alb, BS, and CRP (ABC) score could be used to stratify the patients into groups with significantly different survival rates (p < 0.001, log-rank test). Our ketogenic diet regimen is considered to be a promising support therapy for patients with different types of advanced cancer.

Although previous studies suggest that cancer cachexia is a poor prognostic factor for immune checkpoint inhibitor monotherapy, the impact of cancer cachexia on chemoimmunotherapy is unclear. We investigated the impact of cancer cachexia on the therapeutic outcomes of chemoimmunotherapy for non-small cell lung cancer (NSCLC). We retrospectively analyzed patients’ medical records with NSCLC who received chemoimmunotherapy in 12 institutions in Japan between January and November 2019. We defined cancer cachexia as weight loss exceeding 5% of the total body weight or a body mass index of < 20 kg/m² and weight loss of more than 2% of the total body weight within 6 months before chemoimmunotherapy initiation, with laboratory results exceeding reference values. This study enrolled 235 patients with NSCLC, among whom 196 were eligible for analysis, and 50 (25.5%) met the criteria for cachexia diagnosis. Patients with cancer cachexia had a significantly higher frequency of a programmed death-ligand 1 (PD-L1) expression of ≥ 50% (48%, p = .01) and shorter progression-free survival (PFS; log-rank test: p = .04) than patients without cachexia. There was no significant difference in overall survival (OS) between the cachexia and no-cachexia groups (log-rank test: p = .14). In the PD-L1 ≥ 50% population, there was no significant difference in PFS and OS (log-rank test: p = .19 and p = .79, respectively) between patients with NSCLC in the cachexia or no-cachexia groups. Cancer cachexia might be a poor prognostic factor in patients with NSCLC receiving chemoimmunotherapy.

Combination therapy with immune checkpoint inhibitors and cytotoxic chemotherapies (chemoimmunotherapy) is associated with significantly better survival outcomes than cytotoxic chemotherapies alone in patients with advanced non-small cell lung cancer (NSCLC). However, there are no prognostic markers for chemoimmunotherapy. The prognostic nutritional index (PNI) and lung immune prognostic index (LIPI) are prognostic biomarkers for immune checkpoint inhibitor (ICI) monotherapy or cytotoxic chemotherapies. Thus, we aimed to examine whether these factors could also be prognostic markers for chemoimmunotherapy. We retrospectively examined 237 patients with advanced NSCLC treated with chemoimmunotherapy. In the total group, the median overall survival (OS) was not reached, and the median progression-free survival (PFS) was 8.6 months. Multivariate analysis of OS and PFS revealed significant differences based on PNI and LIPI. Programmed cell death ligand 1 (PD-L1) was also significantly associated with OS and PFS. PNI and a PD-L1 tumor proportion score (TPS) of <50% and poor LIPI (regardless of PD-L1 TPS) were associated with poor prognosis. PNI and LIPI predicted survival outcomes in patients with advanced NSCLC treated with chemoimmunotherapy, especially in patients with PD-L1 TPS <50%. For patients in this poor category, chemoimmunotherapy may result in a worse prognosis than expected.