TM-5614

There is no established standard 3^rd line treatment for patients with advanced non-small cell lung cancer (NSCLC). Although cytotoxic chemotherapeutic agents that are not used as 1^st or 2^nd line treatment are administrated as 3^rd line treatment, their anti-tumor efficacy is insufficient. Anti-programmed death ligand-1 (PD-L1)/programmed death-1 (PD1) treatment is more effective and less toxic than chemotherapy in anti-PD-L1/PD-1 treatment-naïve patients with NSCLC. Therefore, anti-PD-L1/PD-1 therapy is considered an appropriate 3^rd line treatment. However, the anti-tumor efficacy is limited in patients previously treated with anti-PD-L1/PD-1 antibody. Today, new drugs are needed to increase the efficacy of anti-PD-L1/PD-1 antibodies.

This open-label, single-arm, investigator-initiated phase II study is designed to evaluate combination treatment of nivolumab and TM5614, a plasminogen activator inhibitor (PAI-1) inhibitor as 3^rd or more line treatment in NSCLC patients who underwent standard treatment. The primary endpoint is the objective response rate and the secondary endpoints are progression-free survival (PFS), overall survival (OS), duration of response (DOR) and safety. Recruitment began in September 2023 and is expected to continue for approximately three years.

Currently, there is no standard 3^rd line treatment for advanced NSCLC, and we hope that the findings of this study will facilitate more effective treatments in this setting. Ethics and dissemination: the study protocol conformed to the ethical principles outlined in the Declaration of Helsinki. All patients will provide written informed consent prior to enrollment. Results will be published in a peer-reviewed publication.

This study is registered to Japan Registry of Clinical Trials with number: jRCT2061230039 (19/July/2023).

Congenital fibroblast growth factor 23 (FGF23)‐related hypophosphatemic rickets/osteomalacia is a rare bone metabolism disorder characterized by hypophosphatemia and caused by genetic abnormalities that result in excessive secretion of FGF23. Hyp mice are a model of X‐linked hypophosphatemia (XLH) caused by deletion of the PHEX gene and excessive production of FGF23. The purpose of this study was to investigate the potential of TM5614 as a therapeutic agent for the treatment of congenital FGF23‐related hypophosphatemic rickets and osteomalacia in humans by administering TM5614 to Hyp mice and examining its curative effect on hypophosphatemia. After a single oral administration of TM5614 10 mg·kg−1 to female Hyp mice starting at 17 weeks of age, the serum phosphate concentration increased with a peak at 6 h after administration. ELISA confirmed that TM5614 administration decreased the intact FGF23 concentration in the blood. Expression of 25‐hydroxyvitamin D‐1α‐hydroxylase protein encoded by Cyp27b1 mRNA in the kidney was suppressed in Hyp mice, and treatment with 10 mg·kg−1 of TM5614 normalized the expression of 25‐hydroxyvitamin D‐1α‐hydroxylase protein and Cyp27b1 mRNA in the kidneys of these mice. Our data indicate that oral administration of TM5614 ameliorates hypophosphatemia in Hyp mice, suggesting that TM5614 may be an effective treatment for congenital FGF23‐related hypophosphatemic rickets and osteomalacia.