(Medical Xpress)—University of Adelaide researchers have discovered that a new trial vaccine offers the most promising treatment to date for melanoma that has spread, with increased patient survival rates and improved ability to stop or reverse the cancer.
The vaccine, known as vaccinia melanoma cell lysate (VMCL), was given regularly as a treatment to 54 South Australian patients with advanced, inoperable melanoma over a 10-year period.
The long-term results of the study have now been published online in the Journal for ImmunoTherapy of Cancer.
Australia has the highest skin cancer incidence rate in the world and the highest rate of melanoma, which is the most aggressive and deadly form of skin cancer.
"Whichever of the currently available treatments we use, survival of patients with advanced melanoma remains extremely poor," says the leader of the study, Associate Professor Brendon Coventry from the University of Adelaide's Discipline of Surgery and the Royal Adelaide Hospital.
"For patients in the later stages of melanoma, there is a desperate need for improved treatments that stop and reverse the cancer, leading to long-term survival and improved quality of life.
"In our study, over 15% of patients survived for more than five years while receiving successive vaccinations with VMCL. This is especially significant when you consider that all of our patients had advanced stage IV and stage III melanoma. The longest survivor, who was diagnosed with stage IV melanoma, is still alive and well now over 10 years after his treatment began, which is a fantastic result for him and his loved ones," Associate Professor Coventry says.
"Up to 30% of our patients survived almost two years or longer. These rates of survival are remarkable compared with other current treatments. Additionally, it has not been associated with toxic side-effects."
Associate Professor Coventry says that in one case, the vaccine led to a rapid decrease in the number and size of tumours on a patient's leg. "This resulted in substantial improvements in her ability to walk and care for herself within months of the first treatment," he says.
Associate Professor Coventry says that successive vaccination with VMCL over an extended period could repeatedly "boost" or "reset" the patients' immune responses, leading to improved outcomes.
"This represents a major step forward in cancer control - it is proving to be a clinically effective technique," he says. "However, more research is now needed to work out how to optimise this treatment. For example, we believe that by better understanding how to synchronise the vaccination with the body's own natural immune response, we might be able to lead to even longer survival rates for patients."
The complete study is available online: www.immunotherapyofcancer.org/content/pdf/2051-1426-2-9.pdf