Webinar Recap: What to Expect With Keytruda for Advanced Mesothelioma

The U.S. Food and Drug Administration approved the use of Keytruda in combination with chemotherapy as a first-line treatment for advanced pleural mesothelioma on September 17, 2024. Keytruda, an immunotherapy drug, is the brand name for pembrolizumab.

Patient Advocates at The Mesothelioma Center Karen Selby, R.N. and Dr. Catherine Perrault explained during our recent webinar that this establishes a new standard of mesothelioma treatment. Because this rare cancer is so often diagnosed at a late stage, this newly approved use of Keytruda offers new hope.

The FDA granted approval following clinical trials that studied 440 patients with advanced or metastatic pleural mesothelioma. The patients were ineligible for surgery and hadn’t already had chemotherapy or immunotherapy before the trial. 

Patients in the trial received Keytruda  with the chemotherapy drugs Alimta and carboplatin. Their results were compared with patients who only received just chemotherapy.

As Karen noted about the trial’s results, “They were looking at overall survival rate, how long it responded and overall response of the trial.” She added that the results at first glance may appear “unimpressive” until you get to the overall response.  

Clinical Trial 483 Results

• Keytruda with chemo had an overall response rate of 62%. 
• Chemo alone had an overall response rate of 38%. 
• The 2-year survival rate with Keytruda and chemo was 25%.
• The 2-year survival rate with chemo alone was 17%.

Catherine explained these results show new treatment options for mesothelioma are “giving patients time and better quality of life with that time.” She emphasized that Clinical Trial 483 and other trials “will only benefit patients going forward.” 

How Can I Try Keytruda With Chemo?

“Because the FDA has approved this as a first-line treatment, this is something patients can be asking their doctor about,” Catherine said. As with other types of treatment, she noted: “It’s really, really important for us to take into account the different mesothelioma cell types.” 

“Not all mesothelioma is created equal,” Catherine explained. She said Keytruda with Alimta and carboplatin “was shown to be most beneficial for epithelioid mesothelioma. Some patients would benefit less. It does warrant a thorough discussion with your doctor.”

If you weren’t diagnosed with epithelioid mesothelioma, Catherine said it doesn’t necessarily mean you can’t have Keytruda with chemo. However, as Karen explained, “With pleural mesothelioma, the latest studies show epithelioid versus non epithelioid should be treated differently.” 

Immunotherapy may not be a good first option for those with an underlying autoimmune disorder. Chemotherapy may not be a good option for those with other health factors such as kidney disease. Every patient is different. It’s important to discuss the best options for you with your specialist.

What Are the Pros and Cons of Keytruda With Chemo?

For mesothelioma patients at an advanced stage of mesothelioma, Keytruda with chemo can reduce symptoms. Patients experienced less shortness of breath, less pain and overall better quality of life. Karen and Catherine explain there are also potential long-term benefits of immunotherapy, even if it’s discontinued early.

The clinical trial results do show increased toxicity with Keytruda paired with Alimta and carboplatin. Karen and Catherine explained this is because of the combined effects of using 3 drugs together. Keytruda plus chemo had a toxicity rate of 27%. Chemo alone had a toxicity rate of 15%.

Fatigue and nausea were the most commonly reported side effects during the clinical trial. Karen noted, “It can be hard to know if these symptoms are from treatment or mesothelioma itself.”

Chemo side effects are considered predictable. As Karen said, “Physicians are very familiar with these chemo side effects.” Mesothelioma doctors are prepared to help patients manage them. Immunotherapy side effects can be less predictable. 

People on immunotherapy can experience inflammation. Some patients develop conditions such as pneumonitis and colitis. Karen noted this “usually indicates immunotherapy is working, but it could mean you’ll be removed from immunotherapy.” She advised, “Journal all of your side effects.”

What Costs Are Associated With Keytruda and Chemo?

As Catherine noted, “Costs will be highly dependent on insurance. Medicare does often cover it, but it doesn’t mean no costs.” 

Catherine and Karen explained that some insurance companies may request patients try chemo alone first. Chemo is still the gold standard and is considered a cost-effective treatment option. This can unfortunately delay the immunotherapy treatment your doctor recommended.

Our Patient Advocates can also help you and your family navigate insurance and options for financial assistance. If you’re a veteran, our VA-accredited claims agents can also help you file your VA benefits claim.