A phase I study of LCL161, a novel oral pan-inhibitor of apoptosis protein (IAP) antagonist, in Japanese patients with advanced solid tumors

INTRODUCTION

LCL161 is a novel oral pan-inhibitor of apoptosis protein (IAP) antagonist. LCL161 enhances paclitaxel activity in cell lines and xenograft models. A phase I study of LCL161 combined with paclitaxel for the treatment of Japanese patients with advanced solid tumors was conducted.

METHODS

Each patient received oral LCL161 in a single weekly dose on days 1, 8, and 15 of a 21-day treatment cycle. In the second cycle, patients received a combination treatment with weekly paclitaxel (80 mg/m² ) whenever possible. A Bayesian logistic regression model by escalation with the overdose control principle was used.

RESULTS

Nine patients were treated with LCL161 at a dose of 600 mg (five patients) or 1200 mg (four patients). Seven patients were treated with LCL161 plus paclitaxel, and two patients received only LCL161 monotherapy. Because this study was terminated early due to a change in the LCL161 development strategy, the maximum tolerated dose (MTD) was not determined. One patient treated with LCL161 monotherapy at a dose of 1200 mg experienced dose limitind toxicity (grade 3 maculopapular rash). Another patient died on day 86 of bacterial pneumonia, which was suspected to be related to the study treatment. The most common serious adverse events were infections and infestations (n = 3).

CONCLUSION

The present study suggests that the risk of infection may increase when LCL161 is combined with paclitaxel, but other conclusions about the MTD, pharmacokinetic profile, and preliminary activity of the combination of LCL161 plus paclitaxel were not drawn.

Limited increase in antibody titers following mRNA SARS-CoV-2 vaccination for more than 3 years after final dose of anti-CD20 antibody

We investigated the efficacy of BNT162b2 mRNA COVID-19 vaccine in patients with B-cell malignancies treated with anti-CD20 antibody. Although T-cell-mediated immune responses were detected even in patients receiving R-CHOP treatment, the S1 antibody titer following BNT162b2 vaccination remained only marginally increased for more than 3 years after the final dose of anti-CD20 antibody. We found no relationship between the percent of B-cells and S1 antibody titer. The duration of this suppression was much longer than we anticipated. Further protection and treatment strategies against COVID-19 for these patients are warranted.

Microsatellite instability-high colorectal cancer patient-derived xenograft models for cancer immunity research

Context

There is an increasing demand for appropriate preclinical mice models for evaluating the efficacy of cancer immunotherapies.

Aims

Therefore, we established a humanized patient-derived xenograft (PDX) model using microsatellite instability-high (MSI-H) colorectal cancer (CRC) tissues and patient-derived peripheral blood mononuclear cells (PBMCs).

Subjects and Methods

The CRC tissues of patients scheduled for surgery were tested for MSI status, and CRC tumors were transplanted into NOD/LtSz-scid/IL-2Rg-/-(NSG) mice to establish MSI-H PDX models. PDX tumors were compared to the original patient tumors in terms of histological and genetic characteristics. To humanize the immune system of MSI-H PDX models, patient PBMCs were injected through the tail vein.

Results

PDX models were established from two patients with MSI-H CRC; one patient had a germline mutation in MLH1 (c.1990-2A > G), and the other patient had MLH1 promoter hypermethylation. PDX with the germline mutation was histologically similar to the patient tumor, and retained the genetic characteristics, including MSI-H, deficient mismatch repair (dMMR), and MLH1 mutation. In contrast, the histological features of the other PDX from a tumor with MLH1 promoter hypermethylation were clearly different from those of the original tumor, and MLH1 promoter hypermethylation and MSI-H/dMMR were lost in the PDX. When T cells from the same patient with MLH1 mutation were injected into the PDX through the tail vein, they were detected in the PDX tumor.

Conclusions

The MSI-H tumor with an MMR mutation is suitable for MSI-H PDX model generation. The PBMC humanized MSI-H PDX has the potential to be used as an efficient model for cancer immunotherapy research.

Safety and Immunogenicity of the COVID-19 vaccine BNT162b2 in patients undergoing chemotherapy for solid cancer

Background

Although COVID-19 severity in cancer patients is high, the safety and immunogenicity of the BNT162b2 mRNA COVID-19 vaccine in patients undergoing chemotherapy for solid cancers in Japan have not been reported.

Methods

We investigated the safety and immunogenicity of BNT162b2 in 41 patients undergoing chemotherapy for solid cancers and in healthy volunteers who received 2 doses of BNT162b2. We evaluated serum IgG antibody titers for S1 protein by ELISA at pre-vaccination, prior to the second dose and 14 days after the second vaccination in 24 cancer patients undergoing cytotoxic chemotherapy (CC group), 17 cancer patients undergoing immune checkpoint inhibitor therapy (ICI group) and 12 age-matched healthy volunteers (HV group). Additionally, inflammatory cytokine levels were compared between the HV and ICI groups at pre and the next day of each vaccination.

Results

Anti-S1 antibody levels were significantly lower in the ICI and CC groups than in the HV group after the second dose (median optimal density: 0.241 [0.063–1.205] and 0.161 [0.07–0.857] vs 0.644 [0.259–1.498], p = 0.0024 and p < 0.0001, respectively). Adverse effect profile did not differ among the three groups, and no serious adverse event occurred. There were no differences in vaccine-induced inflammatory cytokines between the HV and ICI groups.

Conclusion

Although there were no significant differences in adverse events in three groups, antibody titers were significantly lower in the ICI and CC groups than in the HV group. Further protection strategies should be considered in cancer patients undergoing CC or ICI.

Open-label phase II study of the efficacy of nivolumab for cancer of unknown primary

BACKGROUND

Cancer of unknown primary (CUP) has a poor prognosis. Given the recent approval of immune checkpoint inhibitors for several cancer types, we carried out a multicenter phase II study to assess the efficacy of nivolumab for patients with CUP.

PATIENTS AND METHODS

Patients with CUP who were previously treated with at least one line of systemic chemotherapy constituted the principal study population. Previously untreated patients with CUP were also enrolled for exploratory analysis. Nivolumab (240 mg/body) was administered every 2 weeks for up to 52 cycles. The primary endpoint was objective response rate in previously treated patients as determined by blinded independent central review according to RECIST version 1.1.

RESULTS

Fifty-six patients with CUP were enrolled in the trial. For the 45 previously treated patients, objective response rate was 22.2% [95% confidence interval (CI), 11.2% to 37.1%], with a median progression-free survival and overall survival of 4.0 months (95% CI, 1.9-5.8 months) and 15.9 months (95% CI, 8.4-21.5 months), respectively. Similar clinical benefits were also observed in the 11 previously untreated patients. Better clinical efficacy of nivolumab was apparent for tumors with a higher programmed death-ligand 1 expression level, for those with a higher tumor mutation burden, and for microsatellite instability-high tumors. In contrast, no differences in efficacy were apparent between tumor subgroups based on estimated tissue of origin. Adverse events were consistent with the known safety profile of nivolumab. No treatment-related death was observed.

CONCLUSIONS

Our results demonstrate a clinical benefit of nivolumab for patients with CUP, suggesting that nivolumab is a potential additional therapeutic option for CUP.

Device-related Mycobacterium mageritense Infection in a Patient Treated with Nivolumab for Metastatic Breast Cancer

Treatment with anti-programmed cell death-1 (PD-1) antibodies improves the anti-cancer immune response and can provide a meaningful clinical benefit to cancer patients. However, this treatment can result in specific autoimmune toxicities, termed immune-related adverse events (irAEs). Although irAEs are well recognized, the development of infectious diseases due to this treatment is not often observed. Some recent reports have indicated that patients who receive anti-PD-1 antibodies are at a higher risk for tuberculosis than others. However, reports on nontuberculous mycobacterial infection during anti-PD-1 antibody treatment are still rare. We herein report the first case of Mycobacterium mageritense infection during anti-PD-1 antibody treatment.

Pharmacokinetics, Safety, and Efficacy of Trastuzumab Deruxtecan with Concomitant Ritonavir or Itraconazole in Patients with HER2-Expressing Advanced Solid Tumors

PURPOSE

To evaluate drug-drug interactions between the human epidermal growth factor receptor 2 (HER2)-targeted antibody-drug conjugate trastuzumab deruxtecan (T-DXd; DS-8201a) and the OATP1B/CYP3A inhibitor ritonavir or the strong CYP3A inhibitor itraconazole.

PATIENTS AND METHODS

Patients with HER2-expressing advanced solid tumors were enrolled in this phase I, open-label, single-sequence crossover study (NCT03383692) and received i.v. T-DXd 5.4 mg/kg every 3 weeks. Patients received ritonavir (cohort 1) or itraconazole (cohort 2) from day 17 of cycle 2 through the end of cycle 3. Primary endpoints were maximum serum concentration (C max) and partial area under the concentration-time curve from beginning of cycle through day 17 (AUC17d) for T-DXd and deruxtecan (DXd) with (cycle 3) and without (cycle 2) ritonavir or itraconazole treatment.

RESULTS

Forty patients were enrolled (cohort 1, n = 17; cohort 2, n = 23). T-DXd C max was similar whether combined with ritonavir [cohort 1, cycle 3/cycle 2; 90% confidence interval (CI): 1.05 (0.98-1.13)] or itraconazole [cohort 2, 1.03 (0.96-1.09)]. T-DXd AUC17d increased from cycle 2 to 3; however, the cycle 3/cycle 2 ratio upper CI bound remained at ≤1.25 for both cohorts. For DXd (cycle 3/cycle 2), C max ratio was 0.99 (90% CI, 0.85-1.14) for cohort 1 and 1.04 (0.92-1.18) for cohort 2; AUC17d ratio was 1.22 (1.08-1.37) and 1.18 (1.11-1.25), respectively. The safety profile of T-DXd plus ritonavir or itraconazole was consistent with previous studies of T-DXd monotherapy. T-DXd demonstrated promising antitumor activity across HER2-expressing solid-tumor types.

CONCLUSIONS

T-DXd was safely combined with ritonavir or itraconazole without clinically meaningful impact on T-DXd or DXd pharmacokinetics.

Efficacy and safety of nivolumab in Japanese patients with first recurrence of glioblastoma: an open-label, non-comparative study

BACKGROUND

An open-label, non-comparative study assessed the efficacy and safety of nivolumab in Japanese patients with first recurrence glioblastoma.

METHODS

Patients with first recurrence of histologically confirmed World Health Organization Grade IV glioma, after treatment with temozolomide and radiotherapy, received nivolumab 3 mg/kg every 2 weeks until confirmed disease progression (Response Assessment in Neuro-Oncology criteria) or toxicity. Primary endpoint was 1-year overall survival rate assessed by Bayesian approach. The prespecified efficacy criterion was that the Bayesian posterior probability threshold for exceeding the 1-year overall survival of bevacizumab (34.5%) from the Japanese phase 2 study (JO22506) would be 93%.

RESULTS

Of the 50 enrolled patients, 44 (88.0%) had recurrent malignant glioma (glioblastoma, gliosarcoma), and of these, 26 (59.1%) had at least one measurable lesion at baseline. The Bayesian posterior mean 1-year overall survival (90% Bayesian credible intervals) with nivolumab was 54.4% (42.27-66.21), and the Bayesian posterior probability of exceeding the threshold of the 1-year overall survival rate of bevacizumab (34.5%) was 99.7%. Median (90% confidence interval) overall and progression-free survival was 13.1 (10.4-17.7) and 1.5 (1.4-1.5) months, respectively. One partial response was observed (objective response rate 1/26 evaluable patients [3.8%]). Treatment-related adverse event rates were 14.0% for Grade 3-4 and 2.0% for Grade 5; most adverse events resolved and were manageable.

CONCLUSIONS

The 1-year overall survival with nivolumab monotherapy in Japanese patients with glioblastoma met the prespecified efficacy criterion. The safety profile of nivolumab was consistent with that observed in other tumor types.

CLINICAL TRIAL REGISTRATION

JapicCTI-152967.

Deep-Red/Near-Infrared Turn-On Fluorescence Probes for Aldehyde Dehydrogenase 1A1 in Cancer Stem Cells

Accumulating evidence supports that cancer stem cells (CSCs) are responsible for cancer proliferation, metastasis, and therapy resistance; therefore, an effective strategy to identify and isolate CSCs is required urgently. Because of their low invasiveness and high signal/noise ratio, "turn-on" fluorescence probes working in the deep-red/near-infrared (DR/NIR) region are one of the most attractive yet undeveloped tools for CSC detection. Herein, we report DR/NIR turn-on fluorescence probes, CS5-A and CS7-A, targeted to aldehyde dehydrogenase 1A1 as an intracellular CSC marker. In contrast to the conventional "always-on" green-fluorescent ALDEFLUOR, we succeeded in generating high-contrast (signal/noise ratio > 8.3) and wash-free in vitro CSC imaging with the DR probe C5S-A. This probe can facilitate CSC isolation with minimal contamination by autofluorescence from other tissues through fluorescence-activated cell sorting. Furthermore, the NIR absorbance/emission and turn-on properties of C7S-A allow simple and rapid CSC detection in vivo within 15 min.

Docetaxel plus cisplatin in recurrent and/or metastatic non-squamous-cell head and neck cancer: a multicenter phase II trial

The clinical utility of systemic therapy and genomic profiling in non-squamous-cell head and neck cancer (NSCHNC) has not been fully elucidated. This phase II trial evaluated the efficacy and safety of docetaxel and cisplatin combination in the first-line setting. Eligibility criteria were recurrent and/or metastatic NSCHNC; progressive disease within the last 6 months; no prior systemic therapy; and ECOG performance status of 0-1. Patients received docetaxel (75 mg/m² on day 1) and cisplatin (75 mg/m² on day 1), repeated every 21 days for 6 cycles. The primary endpoint was confirmed objective response rate (ORR). The secondary endpoints included progression-free survival (PFS), overall survival (OS), and adverse events. Next-generation sequencing (NGS) was performed using the Ion AmpliSeq Cancer Hotspot Panel v2. Twenty-three patients were enrolled from November 2012 to October 2016, of whom 8 were male. Median age was 57 years. Ninety-six percent of cases were metastatic. Among 22 evaluable patients, confirmed ORR was 45% (95% confidential interval 24-68%). With a median follow-up period of 18.8 months, median PFS and OS were 6.7 and 20.1 months, respectively. Grade 3/4 adverse events included febrile neutropenia (39%) and anemia (22%). No treatment-related deaths were observed. NGS analysis revealed potential treatment targets, including ERBB2, KIT, and ALK. The docetaxel and cisplatin combination regimen can be considered a new treatment option in recurrent and/or metastatic NSCHNC, although primary prophylaxis for febrile neutropenia should be considered. Diverse genomic alterations may lead novel treatment options.This trial was registered with the UMIN Clinical Trials Registry as UMIN000008333 on [September 1st, 2012].

Immunosuppressive effects and mechanisms of three myeloid-derived suppressor cells subsets including monocytic-myeloid-derived suppressor cells, granulocytic-myeloid-derived suppressor cells, and immature-myeloid-derived suppressor cells

Context

Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of immune cells of myeloid lineage. Recent reports have suggested that human MDSC are divided into three subsets: monocytic MDSC (M-MDSC), granulocytic MDSC (G-MDSC), and immature MDSC (I-MDSC). However, the characteristics of each human MDSC subset still remain unclear.

Materials and Methods

To evaluate the immunosuppressive effects and mechanisms, we first performed a T-cell suppression assay using cells obtained from healthy donor peripheral blood samples. The levels of immune inhibitory molecules in the culture supernatant of each MDSC subset were measured to reveal the T-cell suppressive mechanisms. Then, we compared these results with the results from cells obtained from cancer patient blood samples. Finally, we investigated the difference in the frequency of each MDSC subset between the healthy donors and the cancer patients.

Results

Although M-MDSC and G-MDSC suppressed T-cell activation, I-MDSC had no T-cell suppressive effect. We found that the culture supernatant of M-MDSC and G-MDSC contained high levels of interleukin-1 receptor antagonist (IL-1RA) and arginase, respectively, in both healthy donors and cancer patients. No inhibitory molecules were detected in the culture supernatant of I-MDSC. The population of functional MDSC (M-MDSC and G-MDSC) in the total MDSC was significantly increased in cancer patients compared with that in healthy donors.

Conclusions

Although M-MDSC and G-MDSC, which released IL-1RA and arginase, respectively, suppressed T-cell activation, I-MDSC did not have an immunosuppressive effect. The population of functional MDSC was increased in cancer patients compared with that in healthy donors.

Adipsin-Dependent Secretion of Hepatocyte Growth Factor Regulates the Adipocyte-Cancer Stem Cell Interaction

Simple Summary

Obesity, which is characterized by the excess of adipose tissue, is associated with an increased risk of multiple cancers. We have previously reported that adipsin, a secreted factor from adipocytes, enhances cancer cell proliferation and stem cell properties. In this study, we found that adipsin affected adipocytes themselves and enhanced their secretion of hepatocyte growth factor (HGF). We found that HGF enhanced the adipocyte-cancer cell interactions as a downstream effector of adipsin. Understanding the adipocyte-cancer cell interaction will provide a novel strategy to treat cancers whose initiation, invasion, and metastatic progression are associated with adipose tissues.

Abstract

Adipose tissue is a component of the tumor microenvironment and is involved in tumor progression. We have previously shown that adipokine adipsin (CFD) functions as an enhancer of tumor proliferation and cancer stem cell (CSC) properties in breast cancers. We established the Cfd-knockout (KO) mice and the mammary adipose tissue-derived stem cells (mADSCs) from them. Cfd-KO in mADSCs significantly reduced their ability to enhance tumorsphere formation of breast cancer patient-derived xenograft (PDX) cells, which was restored by the addition of Cfd in the culture medium. Hepatocyte growth factor (HGF) was expressed and secreted from mADSCs in a Cfd-dependent manner. HGF rescued the reduced ability of Cfd-KO mADSCs to promote tumorsphere formation in vitro and tumor formation in vivo by breast cancer PDX cells. These results suggest that HGF is a downstream effector of Cfd in mADSCs that enhances the CSC properties in breast cancers.

Exploratory Analysis to Predict Optimal Tumor Burden for Starting Lenvatinib in Patients With Radioiodine-Refractory Differentiated Thyroid Cancer

Background

We previously reported that a high tumor burden is a prognostic factor based on an analysis of 26 patients with radioactive iodine-refractory differentiated thyroid cancer (RR-DTC) who were treated with lenvatinib. However, the optimal tumor burden for starting lenvatinib still remains to be defined. The aim of this retrospective study was to further explore in the same patient cohort the optimal timing for the start of lenvatinib by focusing on the pre- and post-treatment tumor burden.

Methods

The 26 patients were treated with lenvatinib from 2012 to 2017. We explored the optimal timing for the start of lenvatinib by comparing the characteristics of long-term responders who were defined as patients with progression-free survival ≥ 30 months and non-long-term responders.

Results

Long-term responders had a smaller post-treatment tumor burden at maximum shrinkage than non-long-term responders. Further, post-treatment tumor burden had a strong linear correlation with baseline tumor burden. We created an estimation formula for baseline tumor burden related to prognosis, using these regression lines. Patients with a sum of diameters of target lesions < 60 mm or maximum tumor diameter < 34 mm at baseline were estimated to have significantly better survival outcomes.

Conclusions

We found a strong linear correlation between pre- and post-treatment tumor burden. Our results suggested a cut-off value for baseline tumor burden for long-term prognosis among patients treated with lenvatinib.

Abstract 3083: Role of S100A10 in the metastatic colonization of breast cancer stem cells

Breast cancer is now the most frequently diagnosed cancer and the leading global cause of cancer death in women. Despite advances in the diagnosis and treatment of human breast cancer, advanced stage, metastatic breast cancers are difficult to cure. Among the common target organs for breast cancer metastasis, post recurrence survival is worst when multiple metastasis was observed in the liver. Cancer stem cells (CSCs) are a sub-population of the cells that retain high tumorigenic capacity and, at the same time, are able to sustain the formation of tumors that recreate the cellular diversity of the parent lesions from which they have been originally isolated. We and others have shown that in epithelial malignancies such as breast and colorectal cancers, self-renewal ability of cancer cells with CSC properties is epigenetically regulated by their expression of microRNAs, such as with miR-200c, miR-142 and miR-221. Because of their highly tumorigenic properties, CSCs with are associated with metastatic progression, especially at the initial steps of metastases. We have previously established the breast cancer patient-derived tumor xenograft (PDX) mouse model in which CSC marker CD44+ cancer cells formed spontaneous microscopic metastases in the liver. Comparison of gene expression profiles between the CD44+ human breast cancer cells metastasized to the liver (‘metastasized CSCs') and those in the primary site (‘primary CSCs') revealed that S100A10 was upregulated in metastasized CSCs than in primary CSCs. Knockdown of S100A10 in breast cancer cells reduced the matrix metalloproteinase activity and suppressed their invasion abilities in transwell cell invasion assays in which upper surface of transwell inserts were precoated with Matrigel. Knockdown of S100A10 suppressed, and overexpression of S100A10 enhanced the 3D organoid formation capacities of breast cancer PDX cells in vitro. Finally, constitutive knockdown of S100A10 significantly reduced their metastatic ability to the liver in vivo. Upregulation of S100 family protein expression is observed in many human cancers, including breast, lung, bladder and gastric cancers. These findings suggest that S100A10 functions as a metastasis promoter of breast CSCs by conferring both invasion ability and CSC properties in breast cancers.

Citation Format: Yohei Shimono, Hisano Yanagi, Takashi Watanabe, Tatsunori Nishimura, Takanori Hayashi, Seiji Okada, Motoshi Suzuki, Kenji Kawada, Hironobu Minami, Noriko Gotoh. Role of S100A10 in the metastatic colonization of breast cancer stem cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 3083.

Efficacy and safety of blinatumomab: Post hoc pooled analysis in Asian adults with relapsed/refractory B-cell precursor acute lymphoblastic leukemia

Background

Global studies have demonstrated the efficacy and safety of blinatumomab—a BiTE^® (bispecific T‐cell engager) targeted immuno‐oncology therapy that mediates the lysis of cells expressing CD19 in patients with relapsed/refractory acute lymphoblastic leukemia (R/R ALL). Because limited data are available in Asian patients, we conducted a post hoc pooled analysis in 45 Asian adult patients with R/R ALL—19 from the blinatumomab arm of TOWER (NCT02013167) and 26 from Study 265, a phase 1b/2 study in Japanese adults (NCT02412306).

Methods

Patients received a maximum of two cycles of induction blinatumomab for 4 weeks by continuous intravenous infusion (cycle 1/week 1: 9 μg/day; cycle 1/weeks 2–4: 28 μg/day) followed by 2 weeks of no blinatumomab (each 6‐week cycle); patients received 28 μg/day blinatumomab in subsequent cycles.

Results

Twenty of 45 patients enrolled (44%) achieved complete remission with full or partial hematologic recovery compared with 44% in TOWER and 80% and 38% in phase 1b and phase 2, respectively, of Study 265. The Kaplan–Meier (KM) median overall survival was 11.9 months (95% confidence interval [CI], 9.9–17.1) and the KM median duration of relapse‐free survival was 8.9 months (95% CI, 3.8–10.7). Ninety‐three percent of patients had grade ≥ 3 treatment‐emergent adverse events (AEs) compared with 87% in TOWER and 80% and 100% in phase 1b and phase 2, respectively, of Study 265. Five patients (11.4%) had fatal AEs.

Conclusions

The safety and efficacy of blinatumomab in Asian patients were comparable with those reported in previous global studies with no new safety signals.

Guidelines for clinical evaluation of anti-cancer drugs

Clinical studies intended for regulatory approval must demonstrate the clinical benefits of the drug in a target population. Clinical development of a drug proceeds by stepwise clinical studies; after safety and pharmacokinetics are evaluated and the recommended dosage and administration are determined, efficacy and safety are evaluated in an exploratory manner, and finally clinical benefits are compared with conventional standard therapies. Guidelines for the clinical evaluation of anti‐cancer drugs in Japan were established in 1991 and amended in 2006 after molecular‐targeted drugs were introduced. Recent progress in the development of drugs acting on the immune system and cancer genomic medicine targeting rare but important molecular subtypes have altered the strategy for development of anti‐cancer drugs. It is often difficult to conduct a confirmatory randomized controlled study using overall survival as the primary endpoint in rare molecular subtypes, and the primary evaluation of the efficacy of some drugs and subsequent approval is based on the tumor response. As conducting clinical studies for rare subtypes solely within Japan is difficult, drug development needs to be conducted within a global study. However, this requires robust monitoring to detect possible ethnic differences in pharmacokinetics and drug efficacy. Development using the conditional approval system for drugs enforced in 2020 may be considered, when clinical utility is evaluated based on surrogate endpoints. Because of these changes, we have revised the guidelines for the clinical evaluation of anti‐cancer drugs in Japan. To promote global development of anti‐cancer drugs involving Japan, the guidelines have been translated into English.

Recent progress in development of drugs acting on the immune system and cancer genomic medicine targeting rare but important molecular subtypes have altered the strategy for development of anti‐cancer drugs. As conducting clinical studies for rare subtypes solely within Japan is difficult, drug development needs to be conducted within a global study with monitoring possible ethnic differences. Because of these changes, we have revised the guidelines for the clinical evaluation of anti‐cancer drugs in Japan.

Incidence of venous thromboembolism in patients with solid cancers in Japan: retrospective study of 2735 patients

BACKGROUND

The incidence of cancer-associated venous thromboembolism (CA-VTE) in Japan has not been fully investigated.

METHODS AND RESULTS

Clinicopathological information from patients with solid malignancies who first visited our department between November 2011 and March 2018 were retrospectively reviewed from medical records. The primary outcome was incidence of CA-VTE, defined as deep-vein thrombosis (DVT) and/or pulmonary embolism (PE). On median follow-up of 187 days, 91 of 2735 patients (3.3%) developed CA-VTE during their clinical course, giving an incidence rate of 40.7 per 1000 person-years. Of the 91 patients, 75 (82%) were diagnosed with DVT alone, 6 (7%) with PE alone, and 10 (11%) with both DVT and PE. CA-VTE was most frequent in non-small cell lung cancer (10.8%), followed by cancer of unknown origin (5.8%). Forty-four patients (48%) had one or more symptoms at the initial diagnosis of VTE. Five patients (6%) had a normal D-dimer level (≤ 1.0 µg/mL); of these, 2 were asymptomatic.

CONCLUSIONS

In this retrospective study, the incidence of CA-VTE in Japanese patients with cancer was equivalent to that in Western populations. Approximately half of CA-VTE patients were asymptomatic and 6% had normal D-dimer levels, indicating the need for closer attention to occult CA-VTE.

Initial results from a dose finding study of TNO155, a SHP2 inhibitor, in adults with advanced solid tumors

3005

Background: SHP2 transduces signals from activated receptor tyrosine kinases to downstream pathways including MAPK. TNO155 is a selective, allosteric, oral inhibitor of SHP2. Methods: CTNO155X2101 (NCT03114319) is an ongoing first-in-human, open-label dose escalation/expansion trial of TNO155 in adults with advanced solid tumors. The primary objective is to characterize the safety and tolerability of TNO155 and identify regimen(s) for future study. Secondary assessments included pharmacokinetics, pharmacodynamics, and preliminary clinical efficacy. Here we present data from TNO155 single agent escalation. Results: As of 10/26/2020, 118 patients received TNO155 in variable schedules: once (QD; 1.5–70 mg; n = 55) or twice daily (BID; 30–50 mg; n = 25) in a 2 weeks on/1 week off (2w/1w) cycle; or QD in a 3w/1w cycle (30–60 mg; n = 32), or continuously (40 or 50 mg QD; n = 6). The most common cancer diagnoses treated were colorectal (54%), gastrointestinal stromal tumor (16%), non-small cell lung (12%), and head & neck (8%). The median number of prior antineoplastic therapies was 4 (range 1–10). Overall 109 patients (92%) have discontinued study treatment, 94 (80%) for progressive disease and 6 (5%) for adverse events (AEs). TNO155 showed rapid absorption (median day 1 Tmax ̃1.1 hours), an effective median T½ of ̃34 hours, and near dose-proportional exposure at day 14 (power model: AUCτ beta = 1.09 [90% CI 1.02–1.16]). AEs were mostly Grade 1/2 and generally consistent with on-target effects of SHP2 inhibition. The most common treatment-related AEs (all grades) were increased blood creatine phosphokinase (n = 33, 28%), peripheral edema (n = 31, 26%), diarrhea (n = 31, 26%), and acneiform dermatitis (n = 27, 23%). The most common treatment-related Grade ≥3 AEs were decreased platelets (n = 5, 4%), increased aspartate aminotransferase, diarrhea, and decreased neutrophils (each n = 4, 3%). The best observed response was stable disease (SD) per RECIST 1.1, reported in 24 (20%) patients, with a median duration of SD of 4.9 months (range 1.7–29.3). Evidence of SHP2 inhibition, as measured by change in DUSP6 expression by qPCR in paired pre- vs. on-treatment tumor samples, was seen in the majority of patients treated with TNO155 doses ≥20 mg/day (≥25% reduction, 38/42 [90%]; ≥50% reduction, 25/42 [60%]). Analysis of tumor whole-transcriptome RNA sequencing data is ongoing. Conclusions: TNO155 shows favorable pharmacokinetic properties and promising early safety and tolerability data at doses with evidence of target inhibition. The optimal dose using several schedules is still under evaluation. Studies of TNO155 in combination with other agents, including nazartinib (mutant-selective EGFR inhibitor[i]), adagrasib (KRAS G12Ci), spartalizumab (anti-PD-1 antibody), ribociclib (CDK4/6i), and dabrafenib (BRAFi) with LTT462 (ERKi), are ongoing (NCT03114319, NCT04330664, NCT04000529, NCT04294160). Clinical trial information: NCT03114319.

Five-year survival with nivolumab in previously untreated Japanese patients with advanced or recurrent malignant melanoma

We report the 5‐year follow‐up results from a single‐arm, open‐label, multicenter phase II study (ONO‐4538‐08) conducted in Japan. Twenty‐four patients with treatment‐naïve, recurrent, or unresectable stage III/IV malignant melanoma received 3 mg/kg nivolumab every 2 weeks until progressive disease or unacceptable toxicity occurred. The 5‐year overall survival (OS) rate was 26.1%. Five years after the start of nivolumab treatment, there were six survivors. The 5‐year OS rate was 66.7% for patients with a superficial spreading type, 14.3% for acral lentiginous type, and 16.7% for mucosal type. The 5‐year progression‐free survival rate was 17.2%. No new cases of partial response or complete response were observed after 3 years, and overall response and disease control rates were similar to those reported at 3 years. The treatment‐related adverse events reported between the 3‐ and 5‐year follow‐up periods were anemia (grade 2), white blood cell count decrease (grade 2), and psoriasiform dermatitis (grade 2) in one patient each. No new grade 3 or higher treatment‐related adverse events occurred in this period. In conclusion, first‐line treatment with nivolumab in Japanese patients with unresectable or metastatic melanoma resulted in confirmed long‐term survival. No new safety signals were reported in the studied population.

Surgical outcomes of metastatic bone tumors in the extremities (Surgical outcomes of bone metastases)

•

Prognostic factors: primary tumor, visceral metastases, and surgical procedure.

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PS, BI, EQ-5D, and NRS improved at 3 months after surgery.

•

The improvements of PS, BI, EQ-5D, and NRS were maintained for 6 M after surgery.

•

The management of bone metastases must be decided by a multidisciplinary team.

•

The proper management of bone metastasis will reduce postoperative complications.

Background

Skeletal related events due to metastatic bone tumors markedly affect the activities of daily living (ADL) and quality of life (QOL) in cancer patients. We focused on multidisciplinary therapy for metastatic bone tumors. This study aimed to evaluate the outcomes of surgical treatment for metastatic bone tumors in the extremities.

Methods

We retrospectively reviewed 114 patients who underwent surgical treatment for metastatic bone tumors of the extremities between 2008 and 2019 and 69 patients were reassessed for more than 6 months after surgery. The most common primary tumor was renal, followed by lung, thyroid, and breast cancers. We assessed 69 patients’ performance status (PS), Barthel Index (BI) for ADL, EuroQol 5 Dimensions (EQ-5D) for QOL, and numerical rating scale (NRS) for pain and analyzed these postoperative values relative to preoperative values using Friedman’s test. The postoperative overall survival and the prognostic factors were evaluated using the Kaplan-Meier method, the log-rank test and Cox proportional hazards analysis.

Results

The 1-year overall survival rate was 59%, and the median survival time after surgery was 20 months. Primary tumor, visceral metastasis, and surgical procedure were risk factors correlated with overall survival. PS, BI, EQ-5D, and NRS improved at 3 months after surgery and these improvements were maintained for 6 months after surgery regardless of the surgical procedure.

Conclusions

The significant factors affecting survival after surgical treatment for bone metastases included the primary tumor, presence of visceral metastases, and internal fixation without tumor resection or curettage. Surgical treatment for metastatic bone tumors effectively reduced pain and improved PS, ADL, and QOL postoperatively after 3 months.

Abstract PS4-14: Immunological analysis of the combination therapy of nivolumab, paclitaxel and bevacizumab in patients with HER2-negative MBC in NEWBEAT trial (WJOG9917BTR)

Background: Synergistic antitumor effect of combined anti-PD-1 antibody and anti-VEGF agent has been expected, based on previous preclinical data. We have conducted NEWBEAT trial to evaluate efficacy of triple combination regimen of nivolumab + paclitaxel + bevacizumab in patients (pts)with HR+ HER2- MBC or metastatic TNBC, and clinical results were presented in SABCS 2019. A biomarker study (WJOG9917BTR) was conducted to evaluate the VEGF and immune status of these patients. Methods: HER2-negative breast cancer patients in the NEWBEAT trial were enrolled. To explore the biomarkers for the triple combination treatment, immune status and its dynamics were evaluated with multicolor flowcytometry, multiplex ELISA in peripheral blood before and after treatment. Results: Among the 57 patients who were enrolled to the NEWBEAT trial, 50 patients were registered to the biomarker study. The expression of Ki67 and inducible T-cell co-stimulator (ICOS) on T cells increased after treatment, indicating induction of the T cell proliferation and activation. In responder (defined as patients with progression-free survival longer than 1 year, n = 30), the number of naïve CD4+ T cells at pretreatment were higher and effector memory CD4+ T cells were lower than non-responder. On the other hand, CD86+ myeloid DC at pretreatment were lower in non-responder pts. The median concentration of VEGF-A in serum before treatment was 116.065 pg/ml (range: 0-740.23) and decreased below 37 pg/ml at day 8 after treatment. Although serum VEGF-A level is inversely correlated with clinical outcome of pts with anti-PD-1 antibody in previous reports, in this trial VEGF-A high subgroup had better objective response than VEGF-A low subgroup, suggesting that blockade of VEGF by bevacizumab may overcome immunosuppression via VEGF signaling. Interestingly, in recurrent pts , the number of VEGFR-2+ CD4+ T cells / Monocyte were higher, and PD-L1+ CD4+ T cells / Monocyte / myeloid Dendritic Cell tended to be higher than in de novo stage IV pts. These results suggested that immune status of recurrent pts were more immunosuppressive than de novo stage IV pts, and that it might be more effective by the combination therapy to block the VEGF and PD-1 pathways. Moreover, the changes of immune status and dynamics on CD8+ T cells were not observed, suggesting that the therapeutic strategy of breast cancer might require the re-activation of CD8+ effector T cells through the stimulation of antigen-presenting cells followed by modification of CD4+ helper T cells.Conclusions: Our analysis showed the different immune status depending stage, subtype and response in advanced breast cancer pts. The dynamic decrease of serum VEGF-A concentration and high expression of VEGFR-1 or VEGFR-2 in the immune suppressive cells in advanced breast cancer pts suggested that combination treatment with bevacizumab might clinically overcome the immune suppression via inhibition of VEGF-A. (UMIN000029590)

Citation Format: Yukinori Ozaki, Shigehisa Kitano, Junji Tsurutani, Tsutomu Iwasa, Masato Takahashi, Toru Mukohara, Norikazu Masuda, Manabu Futamura, Hironobu Minami, Koji Matsumoto, Hidetaka Kawabata, Makiko Yamashita, Kenichi Yoshimura, Toshimi Takano. Immunological analysis of the combination therapy of nivolumab, paclitaxel and bevacizumab in patients with HER2-negative MBC in NEWBEAT trial (WJOG9917BTR) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS4-14.