Newly diagnosed mesothelioma patients around the world have begun enrolling in a much-anticipated, phase III clinical trial involving an immunotherapy drug combination with groundbreaking potential.

The trial, designed as first-line therapy for unresectable pleural mesothelioma, will measure the effectiveness of nivolumab (Opdivo) and ipilimumab (Yervoy) against standard-of-care chemotherapy.

A presentation this month at the 2017 American Society of Clinical Oncology (ASCO) annual meeting sparked high expectations for the trial, detailing early, impressive effectiveness involving the two drugs in second-line and third-line treatments.

Pharmaceutical giant Bristol-Myers Squibb is sponsoring the latest clinical trial that will include investigational sites in 20 countries and 17 cancer centers across the U.S., including:

Were ultimately hoping [with this trial] to forge a new standard of care for mesothelioma, Dr. Patrick Ma, lead investigator at WVU Cancer Center, told Asbestos.com. Yes, the expectations for this trial are high.

The ASCO presentation in Chicago was based on a multi-center phase II trial in France that included 125 patients with recurrent mesothelioma and measured the effectiveness of nivolumab against a nivolumab and ipilimumab combination.

The disease control rate (DCR) the percentage of patients in which the cancer either does not grow or shrinks was 50 percent at the 12-week mark for those getting the drug combination.

It was 44 percent for those receiving only nivolumab. According to the investigators, previous studies using other second-line treatments managed only a 30 percent DCR.

Tumors shrank in 26 percent of patients getting both drugs and in 17 percent of those receiving just the one. The median progression-free survival (until the cancer worsens) was 5.6 months with the combination and four months with the single drug.

Severe side effects were more common with the drug combination than with nivolumab alone, with 18 percent and 10 percent of patients reporting, respectively.

Our findings suggest that immunotherapy may provide new hope to patients with relapsed mesothelioma, said lead study author Dr. Arnaud Scherpereel of University Hospital of Lille in France. It is too early to conclude whether nivolumab alone or the combination is better.

The phase III trial, which is preparing for 600 participants across the 20 countries, is expected to last until 2021. Newly diagnosed patients with unresectable disease are encouraged to participate.

It is a randomized trial in which the immunotherapy drug combination will be measured against a pemetrexed and cisplatin or carboplatin chemotherapy combination.

The concept of clinical trials needs to be promoted for mesothelioma patients, whose standard of care has been chemotherapy after chemotherapy that has not produced a wonderful response or a satisfactory outcome, Ma said. In a sense, these trials should be seen as just part of modern clinical care.

Unlike chemotherapy, immunotherapy drugs are designed to boost the bodys natural defenses to fight the cancer. They work by blocking the molecules which prevent the immune system from recognizing the cancer as foreign.

Ma, co-leader of the lung cancer program at WVU, believes immunotherapy is the future for many tough-to-treat cancers, including mesothelioma.

In 2015, nivolumab was the first immunotherapy drug approved by the U.S. Food & Drug Administration (FDA) for non-small cell lung cancer as a second-line treatment.

In May, the FDA approved pembrolizumab (Keytruda) in combination with chemotherapy for first-line treatment of non-small cell lung cancer, another first for an immunotherapy drug.

Pharmaceutical company Merck is expected to announce soon its latest mesothelioma clinical trial involving a combination of Keytruda and CRS-207, a drug form of the Listeria bacteria.

More immunotherapy combination trials are on the horizon for many cancers.

We are only at the dawn of the immunotherapy revolution. We are moving inch-by-inch closer to better treatment for these cancers, Ma said. In the big picture of things, there is still so much more we can learn about the immune system that will lead to significant advancements.

Mesothelioma, which has no definitive cure, is an aggressive cancer typically caused by occupational exposure to asbestos. The FDA has not approved a new treatment for first line mesothelioma therapy since 2005.

The majority of patients with pleural mesothelioma live less than 18 months after diagnosis.

People need to pay more attention to this rare disease, Ma said of mesothelioma. It is really emotional walking with them through this [cancer] journey and not having great treatment options. Hopefully now, were closer to finding a better way to treat them.

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Mesothelioma Clinical Trial Opens with High Expectations - Asbestos.com