Researchers Argue Mesothelioma Clinical Trials Need Broader Eligibility

Researchers Argue Mesothelioma Clinical Trials Need Broader Eligibility

Australian researchers find clinical trial eligibility requirements prevent many mesothelioma patients from participating. Without accurate representation in clinical trials, treatments may not be as effective on the general mesothelioma patient population.

Strict eligibility requirements may also prevent patients from receiving lifesaving clinical trial care.

How Did the Researchers Determine Clinical Trials Are Exclusionary?

Australian researchers analyzed pleural mesothelioma patient data from January 2012 to July 2018. They used this data to determine patient eligibility for two clinical trials.

Mesothelioma is a rare cancer with limited treatment options. Researchers use clinical trials to determine new mesothelioma treatment options. They also use clinical trials to find ways to make existing treatments more effective. But, the researchers in the Australian study determined only 50% to 63% of their patients were eligible for the trials.

What Is a Clinical Trial?

Clinical trials are research studies testing new medical approaches.

Researchers analyzed patient data from 133 pleural mesothelioma patients. All patients received outpatient care in Sydney, Australia at:

  • Royal Prince Alfred Hospital OR
  • Chris O’Brien Lifehouse

The researchers compared the patient data with the eligibility requirements for two pleural mesothelioma clinical trials.

Percentage of Treated Australian Patients Ineligible for MAPS and KEYNOTE-028 Clinical Trial

Ineligible for MAPS

50.5% of patients studied were ineligible.

Ineligible for KEYNOTE-028

36.5% of patients studied were ineligible.

Were the MAPS and KEYNOTE-028 Clinical Trial Requirements Significant?

One of the researchers’ findings included the impact of certain eligibility criteria. They analyzed the impact of the clinical trial eligibility criteria on patient outcomes. Patients omitted for “clinically significant criteria” experienced worse survival than those ineligible for other reasons.

Some of the other, more insignificant reasons mentioned included:

  • Advanced age alone
  • NSAID use (nonsteroidal anti-inflammatory drugs)
  • Concurrent cancers

The researchers found these above reasons prevent patients from receiving the immunotherapy drugs included in these trials.

Researchers Find Eligibility Issue Isn’t Tied to Just One Problematic Requirement

No individual factor excluded more than 25% of patients. However, inadequate function in normal life activities, advanced age (>75), comorbid conditions and outside medications had a significant impact on patient ineligibility.

Of the patients analyzed, 50% and 63% met the clinical trial criteria to receive bevacizumab and pembrolizumab, respectively. However, only 3% and 23% received the drugs, respectively. Reportedly, eligible patients couldn’t get the medications because of limited drug access.

Why Is It Important for Clinical Trials to Include More Mesothelioma Patients?

Mesothelioma clinical trials enable patients to access treatments that may improve patient survival. These treatments may be promising but have not yet received U.S. Food and Drug Administration (FDA) approval.

Testing potential mesothelioma treatments on patients that do not represent the general mesothelioma patient population can be problematic. It may result in approval of treatments that are ineffective on patient subgroups not studied.

Up to 50% of patients seen in routine care by the researchers would not meet eligibility criteria for these pleural mesothelioma clinical trials.

The researchers also found mesothelioma patients in clinical trials have longer overall survival times than patients who do not receive treatment through a clinical trial.

In general, clinical trials often do not include higher-risk patient subgroups, such as older patients. But in the case of mesothelioma, the long latency period of the disease may result in a large percentage of elderly patients.

Researchers found a significant disconnect between clinical trial participants and the general mesothelioma population. They reported, “[g]eneralizing results from trial to clinic is challenging and future trials should aim to have more inclusive criteria.”

According to the study, less than 10% of cancer patients take part in clinical trials.

What Is Being Done to Ensure Access to Clinical Trials for Mesothelioma Patients?

The researchers suggest changes to clinical trials to create:

  1. Broader access to the treatment options through clinical trial participation
  2. Wider applicability of clinical trial findings on the general patient population after clinical trial completion

To facilitate evidence-based treatments benefiting more pleural mesothelioma patients the researchers propose:

  • Relaxing clinical trial eligibility criteria
  • Completing subgroup analyses of clinical trial participants
  • Designing clinical trials to measure treatment efficacy in special groups

The researchers believe these changes could help prevent the exclusion of pleural mesothelioma patients based on insignificant reasons, such as advanced age.