Participants with tumor PD-L1 expression < 50% received 200 mg tislelizumab, 600 mg alcestobart and chemotherapy consisting of cisplatin or carboplatin with either pemetrexed or paclitaxel administered intravenously once every 3 weeks for 2-4 cycles followed by surgical removal of the tumor.

Administered as an intravenous infusion once every 3 weeks

Administered as an intravenous infusion once every 3 weeks

75 mg/m^2 administered as an intravenous infusion once every 3 weeks

Administered as an intravenous infusion once every 3 weeks at an area under the curve (AUC) of 5 mg/mL/min

500 mg/m^2 administered as an intravenous infusion once every 3 weeks in participants with non-squamous NSCLC

175 mg/m^2 administered as an intravenous infusion once every 3 weeks in participants with squamous NSCLC

EFS is defined as the time from randomization until any of the following events, whichever occurred first: radiographic disease progression that precludes definitive surgery, local or distant recurrence as assessed by investigator per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1, or death due to any cause. Local recurrence is defined as recurrence in the ipsilateral thorax (lymph node or lung on the same side as Baseline location) including lung parenchyma, bronchial stump, main trachea, hilum or mediastinal lymph nodes (including subcarinal lymph nodes), pleura and chest wall diagnosed by radiological examination and/or histopathological confirmation. Distant recurrence (metastasis) is defined as spread of disease beyond the area of the ipsilateral thorax (including contralateral area and other organs) diagnosed by radiological examination and/or histopathological confirmation. Median EFS was estimated using Kaplan-Meier methodology.

Event-free survival rate is defined as the percentage of participants with none of the following events: radiographic disease progression that precludes definitive surgery, local or distant recurrence as assessed by investigator per RECIST v1.1, or death due to any cause. Local recurrence is defined as recurrence in the ipsilateral thorax (lymph node or lung on the same side as Baseline location) including lung parenchyma, bronchial stump, main trachea, hilum or mediastinal lymph nodes (including subcarinal lymph nodes), pleura and chest wall diagnosed by radiological examination and/or histopathological confirmation. Distant recurrence (metastasis) is defined as spread of disease beyond the area of the ipsilateral thorax (including contralateral area and other organs) diagnosed by radiological examination and/or histopathological confirmation. EFS rates were estimated using the Kaplan-Meier method with the corresponding 95% confidence interval constructed using Greenwood's formula.

OS is defined as the time from the date of randomization to the date of death due to any cause. Median OS was estimated using Kaplan-Meier methodology.

Overall survival rate is defined as the percentage of participants who were still alive at the analysis time points. OS rates were estimated using the Kaplan-Meier method with the corresponding 95% confidence interval constructed using Greenwood's formula.

DFS is defined as the time from the first date of no disease (ie, participants who underwent margin-negative [R0] resection) to local or distant recurrence, as assessed by the investigator according to RECIST v1.1, or death due to any cause, whichever occurred first. Median DFS was estimated using Kaplan-Meier methodology.

Disease-free survival rate is defined as the percentage of participants with none of the following events: Local or distant recurrence as assessed by the investigator per RECIST v1.1, or death due to any cause. Local recurrence is defined as recurrence in the ipsilateral thorax (lymph node or lung on the same side as Baseline location) including lung parenchyma, bronchial stump, main trachea, hilum or mediastinal lymph nodes (including subcarinal lymph nodes), pleura and chest wall diagnosed by radiological examination and/or histopathological confirmation. Distant recurrence (metastasis) is defined as spread of disease beyond the area of the ipsilateral thorax (including contralateral area and other organs) diagnosed by radiological examination and/or histopathological confirmation. DFS rates were estimated using the Kaplan-Meier method with the corresponding 95% confidence interval constructed using Greenwood's formula.

A serious adverse event (SAE) is any untoward medical occurrence that, at any dose:

• Resulted in death
• Was life-threatening
• Required hospitalization or prolongation of existing hospitalization
• Resulted in disability/incapacity
• Was a congenital anomaly/birth defect
• Was considered a significant medical AE by the investigator or sponsor based on medical judgement (eg, may have jeopardized the participant or may require medical/surgical intervention to prevent one of the outcomes listed above).

Immune-mediated adverse events (imAEs) are autoimmune-mediated complications that may develop in response to immunotherapeutic agents. Immune-mediated AEs were collected from the date of first dose of study drug to 90 days after the last dose of study drug, regardless of whether the participant started a new anticancer therapy or prespecified adjuvant treatment. imAEs were identified by the investigator based on a standard process defined in the Protocol.

Feasibility of surgery was assessed by the number of participants who underwent surgical resection (surgery) within 6 weeks of last dose of study drug, had delayed or canceled surgery, the approach of surgery, duration of surgery (see next outcome measure) ,and the number of participants who underwent an exploratory thoracotomy, a surgical procedure in which a cut is made between the ribs to see and reach the lungs or other organs in the chest or thorax. Exploratory thoracotomy was not counted as surgery.

The duration of surgery is defined as the time interval from the start of the surgical procedure to its completion.

Participants with tumor PD-L1 expression ≥ 50% received 200 mg tislelizumab and 600 mg alcestobart intravenously once every 3 weeks for 2-4 cycles followed by surgical removal of the tumor.

Participants with tumor PD-L1 expression < 50% received 200 mg tislelizumab and chemotherapy consisting of cisplatin or carboplatin with either pemetrexed or paclitaxel administered intravenously once every 3 weeks for 2-4 cycles followed by surgical removal of the tumor.

Participants with tumor PD-L1 expression < 50% received 200 mg tislelizumab, 600 mg alcestobart and chemotherapy consisting of cisplatin or carboplatin with either pemetrexed or paclitaxel administered intravenously once every 3 weeks for 2 - 4 cycles followed by surgical removal of the tumor.