Mesothelioma Immunotherapy Drug Keytruda Gets a Boost from Opdivo Study

The company that makes a promising new mesothelioma immunotherapy drug got a boost from a competitor’s study this week. 

The makers of the lung cancer drug Opdivo have released some disappointing results from their latest lung cancer trial. The findings present another setback for Bristol-Myers Squibb. 

But they are good news for Merck, the maker of the mesothelioma immunotherapy drug Keytruda. In the wake of the publication, Merck’s stocks rose while Bristol-Myers’ dropped. 

How Opdivo Works

Opdivo is the brand name for nivolumab. It is a monoclonal antibody that blocks PD-1. PD-1 is a cell surface protein expressed by some lung cancer and mesothelioma tumors. An Australian study estimated that more than 72 percent of mesothelioma patients overexpress PD-1. Opdivo is still under investigation as a mesothelioma immunotherapy drug.

In the new Phase 3 lung cancer trial, Bristol-Myers tried to show that Opdivo could extend survival in people with advanced non-small cell lung cancer. They tested Opdivo in combination with chemotherapy and in combination with their other drug, Yervoy (ipilimumab). 

The median overall survival for patients treated with Opdivo plus chemotherapy was 18.83 months vs. 15.57 months for chemotherapy alone. The difference was not enough to be considered statistically significant. 

A spokesman for Bristol-Myers said the findings were “not what we had hoped for.”

What is the Leading Mesothelioma Immunotherapy Drug?

From a market share perspective, Keytruda (pembrolizumab) is leading the pack as a lung cancer and mesothelioma immunotherapy drug. The new Opdivo trial sent Bristol-Myers stock shares down by 3 percent while Merck’s shares rose about 1 percent. 

Reuters predicted that the news would “further solidify the domination” of Keytruda as a lung cancer treatment.

Opdivo and Keytruda work in similar ways. Both target cells that express the protein PD-1. PD-1 is one of the ways that cancer cells try to hide from the immune system. 

Opdivo and Keytruda received FDA approval in 2015 as second-line treatments for non-small cell lung cancer. A year later, Keytruda showed success as a first-line treatment, too.

PD-1 inhibitors have become an important focus of mesothelioma research in the past two years because its overexpression is so common. A 2018 Australian study determined that 72.4% of mesothelioma patients overexpress PD-1. These patients tended to experience shorter survival than patients without this overexpression. 

Keytruda gained national attention as a potential mesothelioma immunotherapy drug in 2015 after 76 percent of patients tested responded to it. Keytruda actually shrunk the mesothelioma tumors in about a quarter of those patients. 

A PD-1 blocking mesothelioma immunotherapy drug like Opdivo, Keytruda or Bavencio (avelumab) can only help patients who overexpress PD-1. For all other mesothelioma patients, chemotherapy with Alimta (pemetrexed) and cisplatin remains the primary first-line treatment. 

Sources:

“Bristol-Myers releases mixed Opdivo lung cancer results”, Reuters via CNBC, July 24, 2019, https://www.cnbc.com/2019/07/24/bristol-myers-releases-mixed-opdivo-lung-cancer-results.html

“Bristol-Myers Squibb Provides Update on Part 2 of CheckMate -227”, Press Release, Bristol-Myers Squibb, July 24, 2019, https://news.bms.com/press-release/rd-news/bristol-myers-squibb-provides-update-part-2-checkmate-227