Immunotherapy Drug Keytruda Potentially Effective against Mesothelioma

Approved for three other cancers, the new medication has promise for other kinds of difficult-to-treat conditions, including mesothelioma.

Cancer immunotherapy is a kind of treatment in which drugs are used to activate and direct the body's immune system to attack cancer cells. It is a growing area of hopeful research for cancer patients, especially those with stubborn, intractable cancers such as mesothelioma, the rare but devastating asbestos-caused cancer of the linings that surround internal organs, most notably the lungs.

FDA Approval of Keytruda for other Cancers

Keytruda is Merck's brand name for pembrolizumab, a newer immunotherapy medication that was approved in early October 2015 in accelerated fashion by the U.S. Food and Drug Administration for the treatment of advanced non-small cell lung cancer, called NSCLC, the most common kind of lung cancer. Keytruda was approved to treat NSCLC patients who continue to worsen after other treatment types and whose tumors give off a specific protein named PD-L1. Tumors that excrete this protein can be difficult to treat.

The immunotherapeutic drug blocks the pathway of the PD-L1 protein to boost the body's own immunities against cancerous cells.

Citing promising clinical evidence, the FDA granted manufacturer Merck priority review status because of Keytruda's potential for significantly improving the treatment of NSCLC, a serious condition.

In 2014, Keytruda had also been approved to treat advanced melanoma after administration of another kind of immunotherapy and in November 2015, also was approved to treat a certain kind of aggressive metastatic colorectal cancer.

All three of these FDA treatment approvals for Keytruda were through the agency's Breakthrough Therapy Designation program for accelerated development when clinical evidence suggests a drug may be a significant improvement in treatment over existing approaches in a serious or potentially fatal illness.

Keytruda's Potential Impact on Mesothelioma

At the April 2015 annual meeting of the American Association for Cancer Research or AACR, Merck presented positive results of a Keytruda trial called KEYNOTE-028 in 25 patients with pleural mesothelioma. The mesothelioma study was part of a larger evaluation of the drug's effectiveness in 20 different particularly stubborn types of cancer.

According to Merck, the disease control rate in the mesothelioma patients was 76 percent. This represented 28 percent whose tumors responded to Keytruda treatment plus 48 percent whose mesothelioma remained stable.

Merck's data was presented by Dr. Evan Alley of the Abramson Cancer Center at the University of Pennsylvania, who noted that mesothelioma has "very limited treatment options" and that the encouraging results of the preliminary study merit further research into Keytruda's immunotherapeutic impact on mesothelioma patients.

The Australian Connection

In the meantime, Lou Williams, an Australian woman who fought mesothelioma for 13 years after having been exposed to asbestos as a child, was facing the end of her life when she learned of Keytruda as a potential answer, according to She purchased the drug privately and after Keytruda treatment reports "significant shrinking" of her tumors; no longer having to use oxygen; and regaining the ability to walk independently.

Garnering international attention, she has launched a campaign for her country's regulatory process to accelerate consideration of Keytruda approval for treatment of mesothelioma.

Many will watch with keen interest the regulatory processes both in the U.S. and abroad as Keytruda is considered for approval for mesothelioma treatment. In the meantime, anyone suffering from the disease or who has lost a loved one to mesothelioma should speak with a personal injury attorney about potential legal remedies because of the cancer's link to asbestos exposure.

From offices in California, Oregon, Washington and Utah and with co-counsel in Oklahoma and Utah, the lawyers of Brayton Purcell, L.L.P., advocate for asbestos victims and their families across the country.