10157A081801-NCT04267848OpenThis phase III ALCHEMIST trial compares the addition of pembrolizumab to usual chemotherapy versus usual chemotherapy for the treatment of stage IIA, IIB IIIA or IIIB non-small cell lung cancer that has been removed by surgery. Immunotherapy with monoclonal antibodies, such as pembrolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. Chemotherapy drugs, such as cisplatin, pemetrexed, carboplatin, gemcitabine hydrochloride, and paclitaxel, work in different ways to stop the growth of tumor cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. The purpose of this trial is to find out if the addition of pembrolizumab to usual chemotherapy is better or worse than usual chemotherapy alone for non-small cell lung cancer.A081801NCT04267848NationalAdultTreatmentDrug: Carboplatin Drug: Cisplatin Drug: Gemcitabine Hydrochloride Other: Observation Drug: Paclitaxel Biological: Pembrolizumab Drug: Pemetrexed Disodium Other: Quality-of-Life Assessment Other: Questionnaire AdministrationIIINationalLungThis study investigates the following conditions or diseases: Lung Non-Small Cell Carcinoma Lung Non-Small Cell Squamous Carcinoma Lung Non-Squamous Non-Small Cell Carcinoma Stage II Lung Cancer AJCC v8 Stage IIA Lung Cancer AJCC v8 Stage IIB Lung Cancer AJCC v8 Stage IIIA Lung Cancer AJCC v8 Stage IIIB Lung Cancer AJCC v8Reuss, JoshuaGeorgetown University Medical Center : Jeanette Crawford; Lombardi Comprehensive Cancer Center : Jeanette Crawford; Medstar Franklin Square Medical Center; Medstar Washington Hospital CenterThoracic/CNS/H&N/ThyroidOncology GroupLombardi Comprehensive Cancer Center (LCCC); MHRI Washington Cancer Institute; NCA MU NCORP6888Jeanette CrawfordJeanette Crawford+1 202-687-0893crawfojg@georgetown.edu2026.1.0 Build 16 <a href="https://advarra.com" target="_blank">&copy; 2026 Advarra, Inc.</a>