Tumour destroyed in days in mice implanted with “drug factory” beads

Specially-developed “drug factory” beads continually generate a type of protein that helps eradicate cancerous tumours: scientists at Rice University in Texas, US, noticed that mice implanted with the drug factory beads were soon free of mesothelioma cancer growths, a very aggressive type of cancer that forms in the tissue lining around internal organs. The drug factory beads worked exceptionally well to destroy all traces of the tumour in the mice in a matter of days.

The drug factory beads – each around the size of a pinhead – are loaded up with tens of thousands of cells genetically engineered to produce a cytokine called interleukin-2 (IL-2). This cytokine naturally activates white blood cells to fight cancer and has been approved by the US Food & Drug Administration as an immunotherapy treatment for cancer.

Previously tested in mouse models of ovarian and colorectal cancer, the implanted drug factory beads were this time paired with checkpoint inhibitor drugs to treat mice with mesothelioma. While using the drug factory beads on their own in mouse models of mesothelioma saw more than 50% of the tumours destroyed, combining them with a checkpoint inhibitor drug completely destroyed all tumours in seven mice that were treated, in just a few days.

“It’s very hard to treat mesothelioma tumours in mice, like it is in human beings,” said Dr. Bryan Burt, from Baylor College of Medicine. “And what our data show is that delivery of these immunotherapy particles, regionally, to these mice who have mesothelioma, has very provocative and very effective treatment responses. In fact, I’ve not seen these mesothelioma tumours in mice be eradicated, with such efficacy, as we have in this mouse model.”

“I take care of patients who have malignant pleural mesothelioma. This is a very aggressive malignancy of the lining of the lungs. And it’s very hard to treat completely by surgical resection. In other words, there is often residual disease that is left behind. The treatment of this residual disease with local immunotherapy – the local delivery of relatively high doses of immunotherapy to that pleural space – is a very attractive way to treat this disease,” Dr. Burt added.

The drug factory beads have recently been approved for clinical trials in ovarian cancer patients, expected to begin this US fall. The scientists are also planning to start a second clinical trial for patients suffering from mesothelioma and other lung cancers with pleural metastasis.

Category: Features, Pharmaceuticals