Introduction: Immune checkpoint inhibitors (ICIs) have demonstrated long survival for the treatment of advanced non-small cell lung cancer (NSCLC). However, the effect and safety of ICI rechallenge have not been fully evaluated. The aim of this study was to investigate the efficacy and safety of ICI rechallenge in NSCLC patients. Methods: We defined ‘rechallenge’ as re-administration of ICIs for patients who were previously treated with ICIs and discontinued treatment for any reason, and received subsequent chemotherapy. We retrospectively analyzed the histories of 434 patients with advanced NSCLC who received ICIs from December 2015 to December 2017 at seven centers. Results: A total of 317 patients discontinued the ICI treatment, and 14 patients (4.4%) received ICI rechallenge. All 14 patients discontinued the first ICI due to disease progression. Eight patients received the same kind of ICIs, and six patients received different ICIs. Median progression-free survival and overall survival were 1.5 months [95% confidence interval (CI): 0.8–2.6] and 6.5 months [95% CI: 1.4–19.0], respectively. The objective response rate was 7.1%, and the disease control rate was 21.4%. Two of three patients who achieved at least a stable disease, received radiotherapy between the first and second ICIs. Adverse events were not significantly different compared with the first ICIs. Conclusions: In this study, the effect of ICI rechallenge was limited. Careful consideration of the administration of ICI rechallenge is necessary. This report involved a small number of cases, so further large prospective studies are warranted to confirm the efficacy of ICI rechallenge and to investigate predictive markers to identify a patient population in which ICI rechallenge is effective.

Atezolizumab, an anti-programmed death-ligand 1 (PD-L1) agent, is effective and well tolerated in patients with pretreated advanced non-small-cell lung cancer (NSCLC). We assessed its efficacy and safety in Japanese patients through subgroup analyses of the phase 3 OAK study (NCT02008227). Key eligibility criteria of this randomized, controlled, open-label, international study include locally advanced/metastatic NSCLC, ≥ 1 prior platinum-based chemotherapy, age ≥ 18 years, measurable disease (Response Evaluation Criteria in Solid Tumors v1.1), and Eastern Cooperative Oncology Group performance status 0 or 1. Atezolizumab 1200 mg or docetaxel 75 mg/m² was provided intravenously every 3 weeks. Co-primary end points were overall survival (OS) in the intention-to-treat (ITT) population and those with ≥ 1% PD-L1 expression on tumor cells (TC) or tumor-infiltrating immune cells (IC; TC1/2/3 or IC1/2/3). Sixty-four ITT patients were Japanese; 19 had TC1/2/3 or IC1/2/3 status. In Japanese ITT patients, median OS in the atezolizumab arm (n = 36) was longer than the docetaxel arm (n = 28; 21.3 months [95% confidence interval (CI), 11.0-not estimable (NE)] versus 17.0 months [95% CI, 12.5-NE], respectively; hazard ratio 0.80 [95% CI, 0.41-1.57]). In the TC1/2/3 or IC1/2/3 population, median OS was 21.3 months (95% CI, 15.0-NE) and NE in the atezolizumab (n = 11) and docetaxel (n = 8) groups, respectively (hazard ratio, 0.81 [95% CI, 0.22-3.05]). Atezolizumab was generally well tolerated, with no treatment-related deaths. Atezolizumab was effective and well tolerated in pretreated Japanese patients with NSCLC. Results are consistent with the primary analysis of OAK.

BRAF V600 mutations are common in melanoma, thyroid, and non-small-cell lung cancers. Despite dabrafenib and trametinib being standard treatments for certain cancers, their efficacy across various solid tumours remains unelucidated. The BELIEVE trial assessed the efficacy of dabrafenib and trametinib in solid tumours with BRAF V600E/R or non-V600 BRAF mutations. Between October 1, 2019, and June 2022, at least 50 patients with measurable and seven without measurable diseases examined were enrolled in a subcohort of the BELIEVE trial (NCCH1901, jRCTs031190104). BRAF mutated solid tumour cases other than BRAF V600E mutated colorectal cancer, melanoma, and non-small cell lung cancer cases were included. Patients with solid tumours received dabrafenib (150 mg) twice daily and trametinib (2 mg) once daily until disease progression or intolerable toxicity was observed. The primary endpoint was overall response rate (ORR), and secondary endpoints included progression-free survival (PFS), 6-month PFS, and overall survival (OS). Bayesian analysis was performed using a prior distribution with a 30% expected response rate [Beta (0.6, 1.4)]. Fourty-seven patients with measurable disease, mainly with the BRAF V600E mutation (94%), and three others with non-V600E BRAF mutations (V600R, G466A, and N486_P490del) were enrolled. The primary sites included the thyroid gland, central nervous system, liver, bile ducts, colorectum, and pancreas. The confirmed ORR was 28.0%; the expected value of posterior distribution [Beta (14.6, 37.4)] was 28.1%, although the primary endpoint was achieved, not exceeding an unexpectedly high response rate of 60% obtained using Bayesian analysis. The disease control rate (DCR) was 84.0%. The median PFS was 6.5 months (95% confidence interval [CI]; 4.2–7.2 months, 87.8% at 6 months). Responses were observed across seven tumour types. Median OS was 9.7 months (95% CI, 7.5–12.2 months). Additional patients without measurable diseases had a median PFS of 4.5 months. Adverse events (AEs) were consistent with previous reports, with 45.6% of patients experiencing grade ≥3 AEs. This study reported promising efficacy against BRAF V600-mutant tumours. Dabrafenib and trametinib would offer a new therapeutic option for rare cancers, such as high-grade gliomas, biliary tract cancer, and thyroid cancer. This study was funded by the 10.13039/100009619 Japan Agency for Medical Research and Development (22ck0106622h0003) and a Health and Labour Sciences Research Grant (19EA1008).

Epidermal growth factor receptor (EGFR) is the most frequently mutated driver oncogene in nonsmoking-related, non–small cell lung cancer (NSCLC). EGFR-mutant NSCLC has a noninflamed tumor microenvironment (TME), with low infiltration by CD8+ T cells and, thus, immune-checkpoint inhibitors, such as antiprogrammed cell death-1 (anti–PD-1), have weak antitumor effects. Here, we showed that CD8+ T-cell responses were induced by an EGFR-tyrosine kinase inhibitor (TKI) in syngeneic Egfr-mutant NSCLC tumors, which was further pronounced by the sequential dual blockade of PD-1 and vascular endothelial growth factor receptor 2 (VEGFR2). However, the simultaneous triple blockade had no such effect. The PD-1/VEGFR2 dual blockade did not exert tumor-inhibitory effects without pretreatment with the EGFR-TKI, suggesting that the treatment schedule is crucial for the efficacy of the dual blockade therapy. Pretreatment with EGFR-TKI increased the CD8+ T-cell/regulatory T-cell (Treg) ratio, while also increasing the expression of immunosuppressive chemokines and chemokine receptors, as well as increasing the number of M2-like macrophages, in the TME. Discontinuing EGFR-TKI treatment reversed the transient increase of immunosuppressive factors in the TME. The subsequent PD-1/VEGFR2 inhibition maintained increased numbers of infiltrating CD8+ T cells and CD11c+ dendritic cells. Depletion of CD8+ T cells in vivo abolished tumor growth inhibition by EGFR-TKI alone and the sequential triple therapy, suggesting that EGFR inhibition is a prerequisite for the induction of CD8+ T-cell responses. Our findings could aid in developing an alternative immunotherapy strategy in patients with cancers that have driver mutations and a noninflamed TME.

Although chemoradiotherapy for locally advanced lung cancer has the potential for cure, treatment is avoided in patients with interstitial lung disease because of the risk for severe radiation pneumonitis. Interstitial lung abnormalities (ILA) can be evaluated using high-resolution computed tomography (HRCT) to assess interstitial changes. In this study, we retrospectively examined the feasibility and efficacy of chemoradiotherapy for locally advanced lung cancer patients with ILA. Patients who underwent chemoradiotherapy for locally advanced lung cancer at Okayama University Hospital between 2012 and 2015 were reviewed retrospectively. HRCT prior to treatment was evaluated by one pulmonologist and two radiologists using a sequential reading method. Of the 77 patients enrolled in this study, ILA was present in 25 (32.5%) and indeterminate ILA in 24 patients; 28 patients did not have ILA. Desaturation at rest (SpO2 < 95%) and honeycombing on HRCT were not observed in ILA patients. Only one patient with ILA had a low vital capacity (%VC < 80%). Severe radiation pneumonitis (≥Grade 2) occurred in 36.0% of the patients with ILA, but it was controllable; Grade 4 or 5 was not observed. Multivariate analysis showed that >25% of the lung volume receiving >20 Gy was risk factors of severe radiation pneumonitis, but ILA was not. The 2-year survival rates of patients with and without ILA were 56.8% and 74.1%, respectively, but the difference was not significant (P = 0.33). Chemoradiotherapy was feasible and effective in some patient population with ILA without desaturation, low VC and honeycombing on HRCT.