Placebo-controlled Study Comparing Niraparib Plus Pembrolizumab Versus Placebo Plus Pembrolizumab as Maintenance Therapy in Participants With Advanced/Metastatic Non-Small Cell Lung Cancer

Progression-free Survival (PFS) Assessed by BICR - Intent-to-Treat (ITT) Population

PFS is defined as the time from the date of randomization to the date of first objectively documented PD as determined by BICR using RECIST v1.1 or death from any cause in the absence of progression, whichever occurs first. PD is defined as at least a 20% increase in the sum of the diameters of target lesions, taking as reference the smallest sum on study (this includes the baseline sum if that is the smallest on study).

Time frame: Up to 52 months

Overall Survival (OS) - CR/PR Population

OS is defined as the interval of time from the date of randomization to the date of death due to any cause.

Time frame: Up to 52 months

Overall Survival (OS) - ITT Population

OS is defined as the interval of time from the date of randomization to the date of death due to any cause.

Time frame: Up to 52 months

Time to Progression (TTP) in the Central Nervous System (CNS) Assessed by BICR Using RANO-BM Criteria

TTP in the CNS is defined as the time from the date of randomization until the earliest date of documented PD in the CNS as assessed by BICR using Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) criteria. This endpoint was analysed using a cumulative incidence competing-risk analysis, and the cumulative incidence rate was reported.

Time frame: At Month 6, 12, 18, 24, 30, 36, 42 and 48

Progression-free Survival (PFS) as Assessed by the Investigator Using RECIST v1.1

PFS is defined as the time from the date of randomization to the date of first objectively documented PD as determined by investigators using RECIST v1.1 or death from any cause in the absence of progression, whichever occurs first. PD is defined as at least a 20% increase in the sum of the diameters of target lesions, taking as reference the smallest sum on study (this includes the baseline sum if that is the smallest on study).

Time frame: Up to 52 months

CNS-PFS as Assessed by BICR Using RANO-BM Criteria

PFS is defined as the time from the date of randomization to the date of first radiographic progression in the CNS as determined by BICR using RANO-BM criteria or until death due to any cause (whichever occurs first). This endpoint was analysed using a cumulative incidence competing-risk analysis, and the cumulative incidence rate was reported.

Time frame: At Month 6, 12, 18, 24, 30, 36, 42 and 48

Progression-free Survival (PFS) by Programmed Cell Death-ligand 1 (PD-L1) Status

PFS is defined as the time from the date of randomization to the date of first objectively documented PD as determined by BICR using RECIST v1.1 or death from any cause in the absence of progression, whichever occurs first. PD is defined as at least a 20% increase in the sum of the diameters of target lesions, taking as reference the smallest sum on study (this includes the baseline sum if that is the smallest on study). Participants were evaluated by PD-L1 status: Tumor Cells (TCs) ≥1% and TCs \<1%/Not Evaluable.

Time frame: Up to 52 months

Overall Survival by Programmed Cell Death-ligand 1 (PD-L1) Status

OS is defined as the interval of time from the date of randomization to the date of death due to any cause. Participants were evaluated by PD-L1 status: Tumor Cells (TCs) ≥1% and TCs \<1%/Not Evaluable.

Time frame: Up to 52 months

Number of Participants With Minimally Clinically Important Difference (MCID) Status in European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30 (EORTC-QLQ-C30)

The EORTC QLQ-C30 includes 30-items with single and multi-item scales. These included five functional scales (physical functioning \[PF\], role functioning \[RF\], cognitive functioning \[CF\], emotional functioning \[EF\] and social functioning \[SF\]), three symptom scales (fatigue, pain and nausea/vomiting \[N/V\]), a global health status (GHS)/ Quality-of-Life (QoL) scale, and six single items (constipation, diarrhoea, insomnia, dyspnoea, appetite loss \[AL\] and financial difficulties \[FD\]). Response options are 1 to 4. Scores were averaged and transformed to 0 to 100, a high score for functional scales/ GHS/QoL represent better functioning ability or health-related quality-of-life (HRQoL), whereas a high score for symptom scales/ single items represent significant symptomatology. MCID status: Functional scales \& GHS/QoL (Improved: ≥ +10; Stable: \> -10 and \< +10; Worsened: ≤ -10) and Symptom scales (Improved: ≤ -10; Stable: \> -10 and \< +10; Worsened: ≥ +10)

Time frame: Baseline (Predose); Day (D) 1 of Cycle (C)2, C3, C4, C5-C67 (odd cycles only); End of Treatment (EoT, up to approx 49 months); Safety follow-up (SFU) 1 & 2 (up to approx 50 & 52 months)

Changes From Baseline (CFB) in the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire 13-item Lung Cancer-specific Module (EORTC QLQ-LC13)

EORTC QLQ-LC13 is a 13-items questionnaire used in clinical research to assess health-related quality of life in lung cancer patients. The QLQ-LC13 includes questions assessing lung cancer-associated symptoms (Coughing, hemoptysis, dyspnea and site specific pain), treatment-related side effects (sore mouth, dysphagia, peripheral neuropathy and alopecia) and pain medication. Scores are calculated and transformed to range from 0 to 100. For the disease symptoms and side-effects of treatment scales a higher score represents a higher level of symptoms/problems and a negative change from baseline value indicates reduction (i.e. improvement) in symptoms.

Time frame: Baseline (Predose); Day (D) 1 of Cycle (C)2, C3, C4, C5-C67 (odd cycles only); EoT (up to approx 49 months); Safety follow-up (SFU) 1 & 2 (up to approx 50 & 52 months)

Time to Deterioration (TTD) in EORTC Cancer Quality of Life Questionnaire LC13 (EORTC QLQ-LC13)

TTD in lung symptoms is defined as the time from randomization to first onset of ≥10 point increase from baseline with confirmation by a second adjacent ≥10 point increase in the same symptom domain for any of the three symptoms: dyspnea, chest pain, and cough, on the EORTC QLQ-LC13 were scored on a 4-point scale (1=Not at All to 4=Very Much). Using linear transformation, raw scores are standardized, so that scores range from 0-100. A lower score indicates a better outcome. A longer TTD indicates a better outcome.

Time frame: Up to 52 months

Number of Participants With Treatment Emergent (TE) Adverse Events (AEs), Serious TEAEs and Adverse Events of Special Interest (AESIs)

An AE is any untoward medical occurrence in a participant or clinical investigation participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. SAE is defined as any untoward medical occurrence that, at any dose resulted in death, is life threatening, required hospitalization or prolongation of existing hospitalization, resulted in disability/incapacity, is a congenital anomaly/birth defect, other situations and is associated with liver injury or impaired liver function. SAEs are subsets of AEs. TEAE is an event that emerged during treatment having been absent pretreatment or worsened relative to the pretreatment state. AESI is any AE (serious or nonserious) that is of scientific and medical concern specific to niraparib for which ongoing monitoring and rapid communication by the Investigator to the Sponsor is warranted. AEs were coded using the Medical Dictionary for Regulatory Activities (MedDRA) coding system.

Time frame: Up to 52 months

Plasma Concentrations of Niraparib

Blood samples were collected for plasma concentrations of niraparib.

Time frame: Cycle 1 Day 1 (pre-dose, 3 h), Cycle 1 Day 15 (pre-dose, 3 h), Cycle 2 Day 1 (pre-dose, 3 h), Cycle 4 Day 1 (pre-dose), Cycle 7 Day 1 (pre-dose), and End of Treatment (pre-dose); up to approximately 49 months