ClinicalTrials.gov record
Completed Phase 3 Interventional Results available

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

ClinicalTrials.gov ID: NCT04475939

Public ClinicalTrials.gov record NCT04475939. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced May 18, 2026, 3:50 AM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

A Phase 3, Randomized, Double-Blind, Placebo-Controlled, Multicenter Study Comparing Niraparib Plus Pembrolizumab Versus Placebo Plus Pembrolizumab as Maintenance Therapy in Participants Whose Disease Has Remained Stable or Responded to First-Line Platinum -Based Chemotherapy With Pembrolizumab for Stage IIIB/IIIC or IV Non-Small Cell Lung Cancer (ZEAL-1L)

Study identification

NCT ID
NCT04475939
Recruitment status
Completed
Study type
Interventional
Phase
Phase 3
Lead sponsor
GlaxoSmithKline
Industry
Enrollment
666 participants

Conditions and interventions

Interventions

  • Niraparib Drug
  • Pembrolizumab Biological
  • Placebo Drug

Drug · Biological

Eligibility (public fields only)

Age range
18 Years and older
Sex
All
Healthy volunteers
Healthy volunteers not accepted

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Oct 25, 2020
Primary completion
Feb 25, 2025
Completion
Mar 22, 2026
Last update posted
Apr 30, 2026

2020 – 2026

United States locations

U.S. sites
21
U.S. states
14
U.S. cities
21
Facility City State ZIP Site status
GSK Investigational Site Fullerton California 92835
GSK Investigational Site Los Angeles California 90017
GSK Investigational Site Lone Tree Colorado 80128
GSK Investigational Site Norwich Connecticut 06360
GSK Investigational Site Tallahassee Florida 32003
GSK Investigational Site Atlanta Georgia 30322
GSK Investigational Site Newnan Georgia 30265
GSK Investigational Site Niles Illinois 60714
GSK Investigational Site Iowa City Iowa 52242
GSK Investigational Site Worcester Massachusetts 01655
GSK Investigational Site Mineola New York 10016
GSK Investigational Site New York New York 10016-4744
GSK Investigational Site Charlotte North Carolina 28207
GSK Investigational Site Pittsburgh Pennsylvania 15212
GSK Investigational Site Chattanooga Tennessee 37404
GSK Investigational Site Nashville Tennessee 37203
GSK Investigational Site Dallas Texas 75246
GSK Investigational Site San Antonio Texas 78217
GSK Investigational Site Sugar Land Texas 77479
GSK Investigational Site Waco Texas 76712
GSK Investigational Site Fairfax Virginia 22031

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

Non-U.S. locations

This page focuses on the U.S. directory. The official record also lists 166 non-U.S. sites.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT04475939, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Apr 30, 2026 · Synced May 18, 2026

Related: full search, browse by condition, browse by drug or therapy, browse by sponsor, browse by U.S. city.

Open the official record

The complete protocol, eligibility criteria, and contact information for NCT04475939 live on ClinicalTrials.gov.

View official ClinicalTrials.gov record →