NCT00143364 is a Phase 3 clinical trial of varenicline (CP-526,555) in Smoking Cessation, sponsored by Pfizer.

Who is sponsoring NCT00143364?

NCT00143364 is sponsored by Pfizer.

What drugs are being tested in NCT00143364?

Interventions in NCT00143364: varenicline (CP-526,555).

What condition does NCT00143364 study?

NCT00143364 studies Smoking Cessation.

Is NCT00143364 still recruiting?

NCT00143364 is currently completed. Last updated 1 June 2007.

Last reviewed 2007-06-01 · How we verify

NCT00143364

Name: Drug Landscape Pharmaceutical Database
Creator: Drug Landscape
Published: 2026-01-01
License: https://creativecommons.org/licenses/by/4.0/

A Twelve-Week, Double-Blind, Placebo-Controlled, Randomized, Multicenter Study With Follow-up Evaluating the Safety and Efficacy of Varenicline Tartrate ( CP-526,555) in Comparison to Zyban for Smoking Cessation

Completed Phase 3 Last updated 1 June 2007

What this trial tests

Phase 3 trial testing varenicline (CP-526,555) in Smoking Cessation in 1,005 participants. Completed in 1 March 2005.

Timeline

1 June 2003

1 March 2005

Quick facts

Lead sponsor	Pfizer
Phase	Phase 3
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	double
Primary purpose	treatment
Enrollment	1,005
Start date	1 June 2003
Estimated completion	1 March 2005
Sites	15 locations across United States

Drugs / interventions tested

varenicline (CP-526,555) — full drug profile →

Conditions studied

Smoking Cessation — all drugs for Smoking Cessation →

Sponsor

Pfizer — full company profile →

Who can join

Adults 18 to 75, any sex, with Smoking Cessation. Patients with the condition only — healthy volunteers not accepted.

What's being measured

Primary outcomes are the specific endpoints the trial is designed to prove or disprove.

4 week Continuous Quit Rate ( 4 week CQR ) for Weeks 9 -12.

Sponsor's own description

The primary purpose of this study is to evaluate the safety and efficacy of varenicline given for a twelve week treatment period in comparison with placebo and Zyban for smoking cessation.

Publications & conference data

6 peer-reviewed publications reference this trial (live from Europe PMC):

Efficacy of varenicline, an alpha4beta2 nicotinic acetylcholine receptor partial agonist, vs placebo or sustained-release bupropion for smoking cessation: a randomized controlled trial.
Jorenby DE, Hays JT, Rigotti NA, Azoulay S, et al · · 2006 · cited 952× · PMID 16820547 · DOI 10.1001/jama.296.1.56
Smoking cessation for improving mental health.
Taylor GM, Lindson N, Farley A, Leinberger-Jabari A, et al · · 2021 · cited 160× · PMID 33687070 · DOI 10.1002/14651858.cd013522.pub2
Varenicline in smokers with diabetes: A pooled analysis of 15 randomized, placebo-controlled studies of varenicline.
Tonstad S, Lawrence D. · · 2017 · cited 27× · PMID 27223809 · DOI 10.1111/jdi.12543
Pharmacotherapy for smoking cessation: effects by subgroup defined by genetically informed biomarkers.
Schuit E, Panagiotou OA, Munafò MR, Bennett DA, et al · · 2017 · cited 26× · PMID 28884473 · DOI 10.1002/14651858.cd011823.pub2
Immediate versus delayed quitting and rates of relapse among smokers treated successfully with varenicline, bupropion SR or placebo.
Gonzales D, Jorenby DE, Brandon TH, Arteaga C, et al · · 2010 · cited 25× · PMID 20819082 · DOI 10.1111/j.1360-0443.2010.03058.x
Predictors of post-treatment relapse to smoking in successful quitters: pooled data from two phase III varenicline trials.
Heffner JL, Lee TC, Arteaga C, Anthenelli RM. · · 2010 · cited 20× · PMID 20071105 · DOI 10.1016/j.drugalcdep.2009.12.022

Verify or expand the search:

Other recruiting trials for Smoking Cessation

Currently open trials in the same condition.

NCT07420621 — Preliminary Effectiveness of Enhanced Text Message + Incentives · NA · recruiting
NCT07224087 — Development of a MHBC Intervention for Weight Loss and Smoking Cessation for Pre-Bariatric Surgery Patients · Phase 1 · recruiting
NCT07331519 — Integrating Smoking Cessation With Low-dose CT-screening for Lung Cancer · NA · recruiting
NCT07210567 — Mindfulness-based Ecological Momentary Intervention for Smoking Cessation Among Cancer Survivors · NA · recruiting
NCT07129590 — Trauma-Informed Care for Smoking Cessation for Pregnancy · NA · recruiting

Other Pfizer trials

Trials by the same sponsor.

NCT04982848 — Korea Post Marketing Surveillance (PMS) Study of Talzenna® · not yet recruiting
NCT06873191 — A Study to Learn More About Tukysa Once it is Out in the Korean Market · not yet recruiting
NCT07497854 — A Study to Learn About the Study Medicine NURTEC® ODT 75 mg After it is Released Into the Markets in Korea · not yet recruiting
NCT06507904 — A Study to Learn How Different Preparations of Osivelotor Taste and Enter the Blood With Food or Liquids or With an Anta · Phase 1 · not yet recruiting
NCT06864585 — A Study to Learn About the Study Medicine - Zavicefta in Patients With Sepsis or Loss of Kidney Function in Japan · not yet recruiting

Verify against primary sources

ClinicalTrials.gov — authoritative US registry record
WHO ICTRP — international registry index
EU Clinical Trials Register
Sponsor press releases (Google)

Data sources for this page

Trial protocol + status: ClinicalTrials.gov NCT00143364 (US National Library of Medicine, public domain)
Publications: Europe PMC API search by NCT ID, retrieved 10 June 2026
Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
Sponsor: as reported to ClinicalTrials.gov by Pfizer
Last refreshed: 1 June 2007

Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT00143364.

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing