Promising Clinical Trial for Treatment of Pleural Mesothelioma

A Phase I Clinical Trial combining an immunotoxin called SS1P with standard chemotherapy holds promise of yielding better treatment outcomes for patients suffering from pleural mesothelioma.  Malignant mesothelioma is a cancer that occurs in the lining of the chest (pleura), abdomen (peritoneum) or heart (pericardial). 

 

Pleural mesothelioma is the most common form, accounting for up to 80% of all mesotheliomas. All types of mesothelioma are primarily caused by exposure to asbestos, a known carcinogen used in many industrial, manufacturing, and construction products in the United States until the mid 1980’s.

 

Patients suffering from inoperable (unresectable) epithelial pleural mesothelioma can now participate in a Phase 1 Study through the National Cancer Institute (NCI). Standard frontline treatments for mesothelioma patients are surgery, chemotherapy, and radiation therapy. Commonly, a combination chemotherapy using pemetrexed and cisplatin are used to delay progression of the disease, although often with only minimal improved results.

 

Researchers are hoping that using immunotoxin SS1P in combination with pemetrexed and cisplatin will improve outcomes. Immunotoxins are proteins that contain a toxin along with an antibody that binds specifically to target cells, in this case with mesothelin cells, and is internalized by the target cells. Mesothelin are 40-kDa cell surface proteins in mesothelial cells which make up the lining of the lung, chest, and abdomen. The exact function of mesothelin is not known however recent research indicates it may play a role in the spreading of malignant mesothelioma.  The immunotoxin SS1P is a genetically engineered biological agent that can find mesothelioma tumor cells and kill them without harming healthy cells. 

 

Laboratory studies have shown that using SS1P in combination with chemotherapy leads to increased antitumor activity. If successful, this treatment could also be potentially useful to treat peritoneal mesothelioma. This trial is researching toxicities, maximum tolerable dosing and any side effects caused by immunotoxin therapy, as well as any increased survival times and quality of life. 

 

For more information about participating in this clinical trial and eligibility factors, please visit http://www.cancer.gov/clinicaltrials/ft-NCI-08-C-0026.