Rabbit virus proves effective in treatment of multiple myeloma

A team of researchers at the Medical University of South Carolina (MUSC) utilising the myxoma virus (MYXV) to treat multiple myeloma discovered that the method prompted a strong immune response and eliminated the majority of malignant cells associated with the disease in animals.

The team utilised viral oncolytics to target the cancer’s cells, using the virus, which naturally only affects rabbits.  The treatment showed significant advantages over stem cell transplants, which are currently the standard of care for multiple myeloma and often sees patients relapse. The virus completely destroyed the cancer cells in stem cell samples before they were readministered into the patient without the disease reoccurring.

The therapy also showed the ability to lower disease progression in 66% of preclinical mouse models, with 25% becoming disease-free with no relapse. The team theorised that, as the host’s bone marrow remained unaffected by the virus, the immune system within remained functional – a notion reinforced by a documented increase in CD8+ ¬T white blood cells, suggesting the immune system was responding strongly against the cancer.

But while the research produced impactful results, the challenge of increasing the breadth of its effectiveness still looms.

"I think the major next question is 'How do you get that response rate from 25% to 50% to 80% to 100%?'" commented lead author Eric C Bartee. "How do you define the patients in which it works?"

It is believed that combining this treatment with other immunomodulatory therapies could boost anti-tumour response and provide an effective treatment regimen for multiple myeloma.

"I think what our findings, and oncolytics in general, really highlight is that some of these non-traditional therapies can really offer the benefit of complete disease eradication," Bartee continued. "You're not just moving the curve to the right a little bit; you're bending the survival curve up. And you're really fundamentally changing how you can look at cancer treatment."

Multiple myeloma remains notoriously difficult to successfully treat. Manifesting within plasma B cells in the immune system, the disease commonly reoccurs in patients. While a big step forward, the study still has considerable distance to cover in transferring from mice models to humans.

Matt Fellows