A drug normally used to treat and prevent osteoporosis may be useful in the treatment of advanced malignant mesothelioma, too.
The drug, called zoledronic acid, is a member of the drug class bisphosphonates and is also used to prevent skeletal fractures in patients with certain kinds of cancer.
In a new study published in the journal Lung Cancer, University of Alabama researchers found that more than a third of mesothelioma patients treated with zoledronic acid saw some benefit from it and none of them experienced any serious side effects.
Testing Zoledronic Acid for Mesothelioma
Malignant mesothelioma is a fast-growing cancer of internal membranes caused by exposure to asbestos. Conventional cancer therapies do not typically work well for mesothelioma and researchers are continually looking for new and better options.
The new pilot study of zoledronic acid involved eight men with advanced malignant pleural mesothelioma. The median age of the study subjects was 62 and three quarters of them had epithelioid mesothelioma, the most common subtype.
The patients had either failed to respond to previous mesothelioma treatments or had been judged too unhealthy to undergo systemic chemotherapy.
The research team used several factors to measure how well the zoledronic acid worked for these patients, including the patients’ levels of vascular endothelial growth factor (VEGF) and the mesothelioma biomarkers mesothelin and osteopontin.
Modest Impact, No Toxicity
While zoledronic acid did not have a major impact on mesothelioma survival, 37.5 percent of patients did benefit from the treatment. The patients who responded either saw a reduction in the size of their mesothelioma tumors or experienced a temporary cessation of tumor growth.
It took a median of 2 months for those mesothelioma tumors to start growing again after treatment with zoledronic acid, but the longest progression-free survival was 21 months. Median overall survival on the treatment was 7 months. Patients who experienced a drop in VEGF levels were the ones who were most likely to benefit from zoledronic acid.
Equally significant was the fact that there were no treatment-related toxicities associated with zoledronic acid treatment. In contrast, standard chemotherapy treatment for mesothelioma can produce serious side effects and may even be too caustic for the most fragile patients. Zoledronic acid may offer a viable alternative.
“Zoledronic acid shows modest clinical activity without significant toxicity in patients with advanced malignant pleural mesothelioma,” concludes lead author, oncologist Muhammad Omer Jamil, MD.
Zoledronic acid is on the World Health Organization’s List of Essential Medicines, drugs that are considered the safest and most effective for health systems to have on hand.
Jamil, MO, et al, “A pilot study of zoledronic acid in the treatment of patients with advanced malignant pleural mesothelioma”, June 12, 2017, Lung Cancer, pp. 39-44