An antibody drug that medical practitioners already use to help treat cancer has shown promise when given to patients who have mesothelioma.
Investigators from the Perelman School of Medicine at the University of Pennsylvania found that pembrolizumab could offer hope to those who have malignant pleural mesothelioma, the most common form of this cancer.
Around 90 per cent of patients with the disease have pleural mesothelioma, which is primarily caused by asbestos exposure. The hazardous material was previously used in building materials across Australia, and inhalation of asbestos fibres can cause tumours to develop in the pleura – a cell membrane lining the lungs and chest wall.
Between January 1 and December 31 2015, 650 new diagnoses of the disease occurred in the country, according to statistics from the Australian Mesothelioma Registry. Of these, 145 patients were female and 505 were male, with men more at risk due to occupational exposure to asbestos.
How can pembrolizumab help?
The researchers' work, published in March's edition of The Lancet Oncology, involved giving 25 patients with pleural mesothelioma a dose of pembrolizumab every two weeks.
Pembrolizumab is a checkpoint inhibitor, which means it frees up the patient's immune system to fight the cancer. In this case, the drug was delivered to people who had either already undergone chemotherapy or who were unable to receive it.
Nearly half of the patients' tumours shrank and participants saw the progress of their disease cease for an average of six months. While 14 patients have died since the study began two years ago, researchers claimed they were impressed with the results.
"Most patients who receive a second-line therapy have a life expectancy of about six or seven months, so to have four patients still ongoing at two years is very encouraging," said Evan Alley, chief of haematology and medical oncology at Penn Presbyterian Hospital.
Living with mesothelioma
One of the key benefits outlined in the study was that no patients were forced to pull out due to the medication's side effects, which include fatigue, loss of appetite, dry mouth and nausea.
Dr Alley said the drug was "well tolerated" and that multiple studies are currently underway to confirm the research findings. If successful, the drug could become the standard second-line therapy after chemotherapy.
"This study provides evidence that some patients can have long-term disease control with this drug, which we haven't seen before," Dr Alley concluded.
Mesothelioma sufferers and their families will no doubt welcome these developments, particularly given the short life expectancy of patients following diagnosis.