By Clinical Research News Staff 

January 30, 2025 | Researchers in Japan have made significant strides in boron neutron capture therapy (BNCT), a specialized cancer treatment, by incorporating polyvinyl alcohol (PVA)—the primary component of children’s glue—into a boron-based drug. This innovation could significantly enhance the tumor-targeting capabilities of BNCT, a technique that uses neutron irradiation to destroy cancer cells while sparing healthy tissue. 

Dr. Takahiro Nomoto, associate professor at the University of Tokyo, led the study, which demonstrated the effectiveness of combining PVA with D-BPA, a boron-containing compound previously dismissed as ineffective. Published in the Journal of Controlled Release, the findings show that PVA-D-BPA improves the selective accumulation of boron in tumors beyond what is possible with currently approved drugs, potentially broadening BNCT’s clinical applications. 

BNCT, first explored in the U.S. during the 1950s, fell out of favor due to challenges in selectively delivering boron to tumors and issues with neutron beam purity. Japan revived the approach, introducing advanced neutron irradiation systems and boron drugs such as L-BPA, leading to the first BNCT approvals in 2020 for advanced head and neck cancers. 

Building on this legacy, Nomoto’s team has found that adding PVA to D-BPA enhances boron retention in tumors, solving one of BNCT’s long-standing limitations. This is crucial since effective therapy requires prolonged retention of boron during neutron irradiation, which typically lasts 30-60 minutes. 

PVA-D-BPA’s tumor selectivity stems from its interaction with LAT1, a transporter predominantly expressed in cancer cells. Unlike its predecessor L-BPA, which can also accumulate in normal cells, PVA-D-BPA demonstrates enhanced tumor-targeting precision, making it a promising candidate for cancers previously deemed unsuitable for BNCT. 

The research team, in collaboration with Stellar Pharma and other institutions, aims to optimize PVA-D-BPA for clinical use. Animal testing is expected to begin by 2030, with hopes of eventual commercialization. 

BNCT’s resurgence is a testament to Japan’s leadership in cancer therapy innovation. As of November 2024, clinical trials are underway for angiosarcoma, malignant meningiomas, and thoracic malignancies, potentially expanding the therapy’s reach. 

For a more detailed look at BNCT’s history and the latest developments, read the full story at Bio-IT World.