A new Phase 2 clinical trial called CHIMERA is testing whether adding the immunotherapy drug pembrolizumab to standard chemotherapy before and after surgery can dramatically improve outcomes in resectable pleural mesothelioma. The researchers hope that the approach will increase the rate of complete tumor elimination from approximately 5% with chemotherapy alone to 18% in patients who meet surgical criteria.
Mesothelioma Trial Combines Pembrolizumab with Surgery in Three Stages
The CHIMERA trial is enrolling previously untreated adults diagnosed with stage I to IIIa epithelioid or biphasic pleural mesothelioma. To qualify, participants’ tumors must be surgically accessible, the disease must have been caught early, and patients need to be strong and healthy enough to withstand major surgery. Those accepted will receive three cycles of pembrolizumab combined with cisplatin or carboplatin and pemetrexed chemotherapy before surgery and will then undergo pleurectomy/decortication at one of two high-volume Italian surgical centers. They will then receive 14 additional cycles of pembrolizumab afterward.
The primary goal of the mesothelioma trial is achieving what researchers call pathological complete response, which means no residual viable tumor can be found anywhere in the removed tissue or sampled lymph nodes after treatment. With chemotherapy alone, this complete response has only been achieved in 5% of patients for more than a decade. The CHIMERA investigators hope that adding pembrolizumab can push that rate to 18%, a number based on data from earlier mesothelioma trials of immunotherapy, and from similar neoadjuvant combinations tested in resectable lung cancer.
Combination of Immunotherapy and Chemotherapy Offers Hope for Mesothelioma Patients
The mesothelioma trial, which builds on recent advances in mesothelioma immunotherapy, is being sponsored by the Veneto Institute of Oncology in Italy. It has enrolled approximately 40 patients since November 2024. It is tracking major pathological response, overall response rate, event-free survival, overall survival, and treatment feasibility. Researchers are also collecting patients’ blood and tissue samples throughout treatment to see which biomarkers predict response.
In the face of questions about the impact of surgery on mesothelioma care, CHIMERA’s results could help clarify whether adding immunotherapy to perioperative treatment justifies multimodality therapy for carefully selected mesothelioma patients with resectable disease. If you or someone you love has been diagnosed with mesothelioma, the Patient Advocates at Mesothelioma.net are here to help. Contact us today at 1-800-692-8608 to learn more.
