Mesothelioma is a rare cancer affecting only about 3,000 Americans each year. Most of those diagnosed are diagnosed with pleural mesothelioma, but a small number (approx. 500 per year) are diagnosed with peritoneal mesothelioma, which is mesothelioma in the abdominal lining. With so few diagnosed with peritoneal mesothelioma, studying and evaluating the illness has been difficult, and treatments ineffective. However, scientists are researchers are continually exploring new techniques to treat peritoneal mesothelioma, and the latest development from MaxCyte and its collaborators from Johns Hopkins University have them hopeful they are on the right track, as clinical testing has begun for a new anti-tumor drug.
MaxCyte is a biotechnical company that has developed MCY-M11, which is a chimeric antigen receptor (CAR) and is evaluating its effect on mesothelin-expressing solid tumors. For those suffering from peritoneal mesothelioma, the immune system is often in a weakened or in a compromised state; unable to fight infections as the cancer spreads. CARs are proteins that are specifically altered to give T cells – white blood cells that allow the immune system to adapt when an illness strikes – the ability to target particular proteins. MCY-M11 has been administered in non-clinical settings on laboratory animals with tumor growth. Results from those studies showed an overall increase in survival rate after just one injection. Multiple injections over time increased survival further with zero toxic effects outside the tumors.
This has led to FDA approval of a Phase 1 clinical trial of MCY-M11 for those suffering from ovarian cancer and peritoneal mesothelioma. Clinical trials are divided into three phases, with the first phase typically focusing on procedure development and drug administration on a small number of participants. In this Phase 1 trial, which is already underway, MCY-M11 is administered as an intraperitoneal (through the abdomen) infusion for three weeks. Those eligible to participate must have the following:
- Be able to undergo peripheral blood leukapheresis; have successful placement of an intraperitoneal catheter.
- Be diagnosed with one of the following: metastatic or unresectable high grade serous adenocarcinoma involving the ovary, primary peritoneum, or fallopian tube with peritoneal involvement, not including mixed histologies, OR unresectable epithelioid or biphasic peritoneal mesothelioma
- Be at least 4 weeks from previous anti-cancer therapy
- Have a life expectancy of greater than 3 months.
Once administered, MCY-M11 will utilize messenger RNA (mRNA) to create new peripheral blood mononuclear cells (PBMCs). PBMCs are blood cells responsible for fighting infections in the immune system. Scientists are hopeful for a “controlled resistance” that if successful, could become the platform for targeted cell-based immune therapy development.
This Phase 1 clinical trial began in September 2018 and is currently recruiting. The study is expected to complete by December 2020.
U.S National Library of Medicine, “Intraperitoneal MCY-M11 (Mesothelin-targeting CAR) for Treatment of Advanced Ovarian Cancer and Peritoneal Mesothelioma,” ClinicalTrials.gov (August 1, 2018). [Link]