Neoadjuvant APC followed by surgical resection and atezolizumab maintenance meets safety criteria

Neoadjuvant cisplatin and pemetrexed plus aezolizumab followed by surgical resection and maintenance aezolizumab met safety criteria, according to research presented today in OA13: Topics in Pleural Mesothelioma at the IASLC World Conference 2021 on lung cancer.

Dr Anne Tsao of the MD Anderson Cancer Center in Houston and her clinical site co-investigators randomly assigned 24 patients with epithelioid or biphasic histology whose disease was resectable by pleurectomy / decortication (P / D) or extrapleural pneumonectomy (EPP). ), who have undergone prolonged surgery staging by mediastinoscopy or endobronchial ultrasound and laparoscopy, and who have not received prior chemotherapy or immunotherapy.

Safety was defined as the absence of an adverse event of grade 4-5 immune origin; feasible if 18/24 (75%) received at least one dose of maintenance therapy. The patients were divided into two cohorts: the pleurectomy / decortication cohort or the extrapleural penomonectomy cohort.

Patients received four neoadjuvant cycles of cisplatin plus pemetrexed plus atezolizumab (CPA), resection, then radiotherapy (PPE only), followed by one year of maintenance aezolizumab.

Twenty-eight eligible patients were recruited (November 2017 – May 2020); 25 received at least two cycles of neoadjuvant APC, 18 received surgery, and 15 received maintenance aezolizumab. The median age was 68.1 (31.5 to 77.3), with 20 males and eight females.

There were 24 planned pleurectomies / decortications (P / D) and four planned PPE. Twenty-one patients completed neoadjuvant therapy, but seven patients did not perform resection (2 toxicities, 4 disease progression, 1 death). The only treatment-related death occurred as a result of sepsis associated with renal and respiratory failure unrelated to the immune system. Eighteen patients with stable disease or partial response underwent surgical resection; 17 received a P / D and 1 EPP. One patient did not receive surgery specified in the protocol due to progressive disease. Postoperatively, one patient had a fatal cardiovascular event. Sixteen patients signed up to receive maintenance aezolizumab for one year, but one patient was ineligible due to inadequate hematologic function.

To date, no treatment-related adverse events more serious than grade 3 have been reported. Three patients are continuing maintenance treatment with aezolizumab.

Neoadjuvant cisplatin and pemetrexed plus atezolizumab followed by surgical resection and maintenance aezolizumab met the safety criteria. Sixty percent of eligible patients are switched to maintenance aezolizumab, and additional monitoring will assess efficacy and long-term toxicity results. “

Dr Anne Tsao, MD Anderson Cancer Center, Houston