Pembrolizumab shows promise in treatment of mesothelioma

March 20, 2017

Pembrolizumab, an antibody drug already used to treat other forms of cancer, can be effective in the treatment of the most common form of mesothelioma, according to a new study led by investigators from the Perelman School of Medicine at the University of Pennsylvania. The study, published this month in The Lancet Oncology, is the first to show a positive impact from checkpoint inhibitor immunotherapy drugs on this disease.

Malignant pleural mesothelioma is a rare and aggressive cancer that represents about 90 percent of all malignant mesothelioma cases. It's primarily caused by the inhalation of asbestos, a fiber commonly found in some forms of insulation, vinyl floor tiles, and other material. Tumors form in the pleura, a thin membrane of cells that line the lungs and chest wall. Most survive less than a year. This poor prognosis is partially due to the fact that most patients are not diagnosed until they are already at a late stage of the disease. The standard first-line therapy treatment involves chemotherapy, and currently there is no approved second-line therapy.

"There have been a lot of studies looking at different drugs, but researchers have not seen positive results," said the study's lead author Evan Alley, MD, PhD, chief of Hematology and Medical Oncology at Penn Presbyterian Hospital. "But we've found this new class of drugs, checkpoint inhibitors, seems to be more effective than what's been available in the past."

Checkpoint inhibitors are a class of drugs designed to free the body's immune system to fight back against cancer. Pembrolizumab, in particular, has been used to treat melanoma, non-small cell lung cancer, and in some cases, head and neck cancers.

Alley and his team presented data from KEYNOTE-028, an ongoing trial involving 13 different research sites in six different countries all looking at the effect of pembrolizumab on patients with advanced malignancies, including . The study evaluated 25 patients with pleural mesothelioma, all of whom were over the age of 18 and had either already been treated with chemotherapy or were unable to receive it. Patients who had already received another checkpoint inhibitor were not included in the study.

Beginning with the first enrollees two years ago, doctors gave each patient a dose of pembrolizumab every two weeks. The tumor reduced in size in 14 of those patients. On average, patients went about six months without their disease progressing, and overall survival was about 18 months. Fourteen patients passed away during the study, while four were still undergoing treatment as of the study's writing.

"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," Alley said.

The most common side-effects reported were fatigue, nausea, loss of appetite, and dry mouth.

"One great sign in this study is that none of the patients had to stop treatment because of side-effects," Alley said. "Some had temporary stoppages, but they were able to continue. The appears to be well-tolerated."

There are multiple studies going on right now to confirm these findings, which the authors note is a necessary step before the drug can become a standard second-line therapy. "This study provides evidence that some patients can have long-term disease control with this drug, which we haven't seen before," Alley said. "We need to better understand what we can do next to make immunotherapy more effective for more patients."

Alley said there are already plans for trials that will test combination therapies, which will utilize pembrolizumab in conjunction with other treatments. Those studies are expected to launch later this year, including two at Penn.

Explore further: Immunotherapy drug pembrolizumab shows promise for mesothelioma patients

More information: Evan W Alley et al, Clinical safety and activity of pembrolizumab in patients with malignant pleural mesothelioma (KEYNOTE-028): preliminary results from a non-randomised, open-label, phase 1b trial, The Lancet Oncology (2017). DOI: 10.1016/S1470-2045(17)30169-9

Related Stories

Immunotherapy drug pembrolizumab shows promise for mesothelioma patients

April 20, 2015
The PD-1 inhibitor pembrolizumab, a cancer immunotherapy drug, shrank or halted growth of tumors in 76 percent of patients with pleural mesothelioma, a rare and deadly form of cancer that arises in the outer lining of the ...

Study of potential new treatment for mesothelioma open to patients

September 15, 2016
The Baylor College of Medicine Mesothelioma Treatment Center at Baylor St. Luke's Medical Center has begun enrolling patients in a clinical research study looking at an investigational drug in patients with malignant pleural ...

The immunotherapy, pembrolizumab, is active against mucosal melanoma tumors

January 29, 2017
Clinical trials of a new immunotherapy, pembrolizumab, have shown that it prolongs life significantly for patients with bladder cancer and is active against a rare sub-type of melanoma, called mucosal melanoma. The findings ...

Combination of radiation and immune checkpoint therapy holds potential for lung cancer

March 16, 2017
An emerging approach for cancer treatment seeks to combine radiation therapy with immune checkpoint inhibitors (ICPIs) to more effectively control tumors in the chest with an acceptable risk of severe treatment-related side ...

Pembrolizumab elicits significant antitumor activity in head and neck cancer patients

June 6, 2016
Treating head and neck cancer patients with recurrent or metastatic disease with the PD-1 inhibitor pembrolizumab resulted in significant clinical responses in a fifth of the patients from a phase II clinical trial, researchers ...

ASCO: Pembrolizumab is good second-line Tx in urothelial CA

February 21, 2017
(HealthDay)—For patients with advanced urothelial cancer that has recurred or progressed after platinum-based chemotherapy, pembrolizumab is associated with increased overall survival, according to a study published online ...

Recommended for you

CAR-T immunotherapy may help blood cancer patients who don't respond to standard treatments

October 20, 2017
Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine in St. Louis is one of the first centers nationwide to offer a new immunotherapy that targets certain blood cancers. Newly approved ...

Researchers pinpoint causes for spike in breast cancer genetic testing

October 20, 2017
A sharp rise in the number of women seeking BRCA genetic testing to evaluate their risk of developing breast cancer was driven by multiple factors, including celebrity endorsement, according to researchers at the University ...

Study shows how nerves drive prostate cancer

October 19, 2017
In a study in today's issue of Science, researchers at Albert Einstein College of Medicine, part of Montefiore Medicine, report that certain nerves sustain prostate cancer growth by triggering a switch that causes tumor vessels ...

Suicide molecules kill any cancer cell

October 19, 2017
Small RNA molecules originally developed as a tool to study gene function trigger a mechanism hidden in every cell that forces the cell to commit suicide, reports a new Northwestern Medicine study, the first to identify molecules ...

Fundamental research enhances understanding of major cancer gene

October 19, 2017
New research represents a promising step towards better understanding of a key cancer gene. A long-running collaboration between researchers at the Babraham Institute, Cambridge and the AstraZeneca IMED Biotech Unit reveals ...

Gene circuit switches on inside cancer cells, triggers immune attack

October 19, 2017
Researchers at MIT have developed a synthetic gene circuit that triggers the body's immune system to attack cancers when it detects signs of the disease.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.