Credit: CDC
Results of a proof-of-principle study suggest virotherapy can be effective against multiple myeloma (MM).
The study included 2 MM patients who each received a single dose of a measles virus engineered to target myeloma plasma cells (MV-NIS).
Both patients responded to the treatment, with initial reductions in M protein and complete resolution of bone marrow plasmacytosis. One of the patients achieved a complete remission that lasted 9 months.
The patients did experience adverse effects associated with MV-NIS, but all were resolved with appropriate treatment.
“This is the first study to establish the feasibility of systemic oncolytic virotherapy for disseminated cancer,” said Stephen Russell, MD, PhD, of the Mayo Clinic in Rochester, Minnesota.
“These patients were not responsive to other therapies and had experienced several recurrences of their disease.”
Dr Russell and his colleagues described this research in Mayo Clinic Proceedings.
Patient characteristics, treatment
The researchers explained that the 2 patients described in this report were the first to receive MV-NIS at the highest possible dose. They both received the virus at a dose of 1011 TCID50, infused into a superficial arm vein in 100 mL of normal saline over 60 minutes.
Both patients had limited previous exposure to measles (and therefore fewer antibodies to the virus) and essentially no remaining treatment options.
The first patient was a 49-year-old woman with heavily pretreated, light chain MM. Her last relapse was 9 months after her second autologous stem cell transplant, while she was not receiving therapy.
The second patient was a 65-year-old woman with relapsing IgA k MM that was refractory to all approved antimyeloma drugs. Her disease had progressed while she was receiving carfilzomib, pomalidomide, and dexamethasone therapy.
Adverse events
Patient 1 experienced a number of adverse effects related to MV-NIS, including a severe headache during treatment that required clinicians to temporarily stop her infusion.
This was followed by fever, tachycardia, hypotension, severe nausea and vomiting, and a superficial venous thrombosis extending from the wrist to the upper humerus. But all of these events responded to treatment.
Patient 2 also experienced adverse effects related to MV-NIS, including fever, tachycardia, hypotension, and headache. She responded to treatment for these events, and her recurring fever resolved spontaneously after a few hours.
Treatment response
Both patients’ disease responded to MV-NIS. They experienced initial reductions in M protein and complete resolution of bone marrow plasmacytosis at 6 weeks after treatment.
Patient 1 achieved a complete remission that lasted 9 months. A scan at 6 weeks showed the patient had experienced substantial improvement in all 5 of her previously identified lesions.
Although patient 2 initially responded to treatment, her plasmacytomas were progressing at the 6-week mark, and her free light chain level was increasing. Her 6-week scan revealed increased size and FDG uptake in most soft tissue lesions, although a few lesions did show varying degrees of improvement.
