Purpose: This is a phase Ib trial of TAS-116, an oral HSP90 inhibitor, plus nivolumab for colorectal cancer and other solid tumors. Patients and Methods: Enrolled patients received TAS-116 plus nivolumab in a dose-finding part to estimate the recommended dose. Additional patients were enrolled in a dose-expansion part. TAS-116 monotherapy (orally once daily, 80–160 mg) was administered for 2 weeks followed by the combination with nivolumab (intravenously every 2 weeks, 3 mg/kg). The primary endpoint was dose-limiting toxicities (DLT). We also conducted biomarker research using paired samples from repeated blood collections and tumor biopsies. Results: A total of 44 patients with colorectal cancer (n = 29), gastric cancer (n = 8), sarcoma (n = 5), non–small cell lung cancer (n = 1), and melanoma (n = 1) were enrolled. Eleven patients had previously received immune-checkpoint inhibitors. No DLTs were observed at all dose levels, and TAS-116 160 mg was determined as recommended dose. The common grade 3 or worse treatment-related adverse events included liver transaminase increased (7%), creatinine increased (5%), and platelet count decreased (5%). Objective tumor response was observed in 6 patients, including 4 microsatellite stable (MSS) colorectal cancers, 1 microsatellite instability-high colorectal cancer, and 1 leiomyosarcoma, resulting in an objective response rate of 16% in MSS colorectal cancer without prior immune-checkpoint inhibitors. Biomarker analysis showed that TAS-116 inhibited the activity of regulatory T cells in peripheral blood mononuclear cells and tumor-infiltrating lymphocytes. Conclusions: TAS-116 160 mg plus nivolumab had manageable safety profiles and antitumor activity, especially for MSS colorectal cancer patients.

The previous second-line treatment for HER2-positive metastatic breast cancer were ado-trastuzumab emtansine (T-DM1); however, its activity is decreased in tumors with heterogenous, reduced, or loss of HER2 expression. Trastuzumab deruxtecan (T-DXd) has recently been developed as a novel antibody-drug conjugate to overcome resistance to T-DM1. However, clinical evidence on its ability to overcome this resistance is limited. We retrospectively analyzed data for patients with HER2-positive metastatic breast cancer who received T-DXd at our institution from April 2020 to March 2021. We evaluated the associations between clinicopathological and molecular biomarkers and the efficacy of T-DXd. Twenty-two patients were enrolled in this study. The median progression-free survival (PFS) was 9.7 months (95% confidence interval [CI], 7.0–not reached [NR]), and the objective response rate (ORR) was 61.9%. The ORR and PFS were comparable between patients with HER2 immunohistochemistry scores of 3+ and 2+/1+ at initial diagnosis (ORR: 50.0% vs. 72.7%, p = 0.39; median PFS, 9.7 months [95%CI, 2.6–NR] vs. 8.3 months [95%CI, 7.1–NR]; hazard ratio, 1.86 [95%CI, 0.53–6.57], p = 0.34). Two patients with heterogenous HER2 expression had a partial response or long stable disease (≥6 months). Three of four patients with re-biopsy samples after anti-HER2 targeted therapy and with latest HER2 immunohistochemistry scores of 1+ experienced partial responses (75.0%) to T-DXd, but none had responded to prior T-DM1. T-DXd demonstrated favorable activity in clinical practice. Moreover, T-DXd showed meaningful benefit in patients with heterogeneity, reduction, or loss of HER2 expression.

Uterine leiomyosarcoma (uLMS) is a rare gynecologic malignancy for which the currently available treatments do not consistently provide long-term disease control. This study aimed to reveal the current clinical status of uLMS to support future clinical trials. This study enrolled patients with uLMS treated at 53 Japanese institutions from 2000 to 2012. Central pathological review (CPR) was performed. All cases were confirmed by CPR, and epidemiological features, treatment, and prognosis were analyzed statistically. A total of 307 patients were enrolled. A diagnosis of uLMS was confirmed in 266 patients (86.6%) of patients after CPR, of whom data for 259 were analyzed. Of these, 186 (71.8%) patients underwent complete gross resection as primary therapy. Ninety-eight patients received no additional adjuvant therapy, while docetaxel and gemcitabine was the most frequent regimen among 155 patients treated with adjuvant chemotherapy. In all cases, the median overall survival (OS) was 44.2 months. Multivariate analyses of prognostic factors in all cases identified stage III and IV disease, high serum lactate dehydrogenase level, and menopausal status as poor prognostic factors. However, in stage I cases, high serum lactate dehydrogenase level and no adjuvant treatment were identified as poor prognostic factors. The 5-year OS of patients with stage I uLMS treated with adjuvant chemotherapy was significantly better than that of those without adjuvant treatment (67.8% vs 46.7%, P = 0.0461). Despite complete removal of the primary lesion, the clinical course of patients with uLMS was poor due to recurrence of distant metastasis. The application of a suitable biomarker and effective adjuvant chemotherapy are required to improve the prognosis of patients with uLMS.

Morisada T, et al. J Gynecol Oncol. 2025 Apr;36(3):e119. https://doi.org/10.3802/jgo.2025.36.e119

Purpose: We conducted a first-in-human, dose-escalation study, to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics, and activity of TAK-931, a cell division cycle 7 inhibitor, in Japanese patients with advanced solid tumors.Experimental Design: Patients ages ≥20 years received oral TAK-931: once daily for 14 days in 21-day cycles (schedule A; from 30 mg); once daily or twice daily for 7 days on, 7 days off in 28-day cycles (schedule B; from 60 mg); continuous once daily (schedule D; from 20 mg); or once daily for 2 days on, 5 days off (schedule E; from 100 mg) in 21-day cycles.Results: Of the 80 patients enrolled, all had prior systemic treatment and 86% had stage IV disease. In schedule A, 2 patients experienced dose-limiting toxicities (DLTs) of grade 4 neutropenia and the maximum tolerated dose (MTD) was 50 mg. In schedule B, 4 patients experienced DLTs of grade 3 febrile neutropenia (n = 3) or grade 4 neutropenia (n = 1); the MTD was 100 mg. Schedules D and E were discontinued before MTD determination. The most common adverse events were nausea (60%) and neutropenia (56%). Time to maximum plasma concentration of TAK-931 was approximately 1–4 hours postdose; systemic exposure was approximately dose proportional. Posttreatment pharmacodynamic effects correlating to drug exposure were observed. Overall, 5 patients achieved a partial response.Conclusions: TAK-931 was tolerable with a manageable safety profile. TAK-931 50 mg once daily days 1–14 in 21-day cycles was selected as a recommended phase II dose and achieved proof of mechanism.Trial registration ID: NCT02699749Significance: This was the first-in-human study of the CDC7 inhibitor, TAK-931, in patients with solid tumors. TAK-931 was generally tolerable with a manageable safety profile. The recommend phase II dose was determined to be TAK-931 50 mg administered once daily on days 1–14 of each 21-day cycle. A phase II study is ongoing to confirm the safety, tolerability, and antitumor activity of TAK-931 in patients with metastatic solid tumors.

Okamoto A, et al. J Gynecol Oncol. 2020 Oct;32:e16. https://doi.org/10.3802/jgo.2021.32.e16