Lausanne, Switzerland – In a new study, researchers found a neoadjuvant application of RAPTA-T, a metal-based compound, can enhance the efficacy of cisplatin, a standard mesothelioma chemotherapy, for pleural mesothelioma patients.
Studies over the years have found that in many instances, chemotherapy has a low success rate in treating mesothelioma. Despite limited success, the standard of care for pleural mesothelioma has long been considered a combination chemotherapy treatment of pemetrexed and cisplatin. Various reports have seen a median survival of about 12 months. And with a little over 5 months of survival before disease progression. These limitations led researchers to identify newer treatment combinations that can improve the efficacy of this standard of care.
The Clinical Trial of RAPTA-T Chemotherapy for Mesothelioma
This clinical trial explored if another metal-based therapy could improve the effect of platinum-based cisplatin. Researchers noted the limits of chemotherapy alone may be due to the inability to sufficiently distribute the treatment to tumors. It’s because solid tumors have an abnormal structure of blood vessels and often create a high pressure of interstitial fluids. These conditions make it difficult for the chemotherapy to travel effectively throughout the tumors.
With this in mind, researchers wanted to explore if a new class of metal-based drugs called RAPTA could complement cisplatin and improve success rates. Previous preclinical trials had shown RAPTA drugs could inhibit primary tumor growth. It prevent metastasis, while also offering a low toxicity that yields fewer side effects than standard chemotherapy.
In a lab setting, the researchers found a low dose of RAPA-T combined with cisplatin as a first-line treatment enabled higher chemotherapy uptake by the tumors. It also inhibited PARP-1, a nuclear protein that allows for angiogenesis (development of new blood cells) and DNA damage repair. Research has associated high expression of this protein as an indicator of poor prognosis and treatment resistance in tumors. PARP-1 inhibitors decrease the endothelial growth factor in tumors. This means tumors were more responsive to treatment and less likely to metastasize.
Conclusion of RAPTA-T Chemotherapy for Mesothelioma:
Overall, the study showed RAPTA-T in combination with cisplatin could create a better antitumor effect than chemotherapy on its own. The researchers noted the treatment could be used palliatively for advanced mesothelioma, and as a neoadjuvant treatment for resectable mesothelioma. With such promising findings, this early phase trial gave researchers hope that RAPTA-T could become part of a first-line treatment for mesothelioma in the future with further study.