Smoking &Amp; Tobacco CessationNCT04308759
An Innovative Conversational Agent (Quitbot) for Smoking Cessation
A study testing Experimental Smoking Cessation Program in people with Smoking &Amp; Tobacco Cessation, run by Fred Hutchinson Cancer Center at 1 site in United States.
Trial summary
This phase III trial compares two remote digital smoking cessation programs to see how well they work for quitting smoking. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Smoking &Amp; Tobacco Cessation
- What is being tested?
- Experimental Smoking Cessation Program
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 1,647 participants
- Where
- 1 siteUnited States
- Study dates
- 24 Jul 2022to 8 Apr 2026
- Phase
- Interventional
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Age 18 or older
- Smokes at least one cigarette a day for the past 12 months
- Wants to quit cigarette smoking within the next 30 days (consistent with text messaging intervention trials)
- If concurrently using any other nicotine or tobacco products, wants to quit using them within the next 30 days
- Interested in learning skills to quit smoking
- Willing to be randomly assigned to either intervention
Show all 11Show fewer
- Resides in United States (US) and will continue to reside in the US for the next 12 months
- Has at least daily access to their own smartphone
- Has text messaging on their smartphone and knows how to download a smartphone application
- Willing and able to read in English, and
- Not using other smoking cessation interventions (This eligibility requirement helps ensure results are due to the treatments we recommend rather than those that participants are doing on their own.)
Who cannot join
- The reverse of the inclusion criteria
Trial locations and contacts
1 site in 1 country.
United States1 site
Fred Hutch/University of Washington Cancer Consortium
Seattle, Washington, 98109
About this study
Official title: Full Scale Randomized Trial of an Innovative Conversational Agent for Smoking Cessation (QuitBot)
This phase III trial compares two remote digital smoking cessation programs to see how well they work for quitting smoking.
Read the detailed description
OUTLINE:
Participants are randomized to 1 of 2 groups. Both groups receive access to a 42-day quit smoking program.
GROUP I: Experimental QuitBot chatbot program, for 42 days to support quitting smoking. After the completion of study, patients are followed up at 3, 6, and 12 months.
GROUP II: Control SmokefreeTXT text messaging program, for 42 days to support quitting smoking. After the completion of study, patients are followed up at 3, 6, and 12 months.
- Conditions
- Smoking &Amp; Tobacco Cessation
- Being tested
- Experimental Smoking Cessation Program, Control Smoking Cessation Program
- Keywords
- Smoking, smoking cessation, quitting smoking, chatbot
- Medical subject headings
- Smoking, Tobacco Use Cessation, Smoking Cessation
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Experimental Smoking Cessation ProgramOther
Also called Experimental
Participate in Quitbot experimental cessation program
Control Smoking Cessation ProgramOther
Also called Control
Participate in Quitbot control cessation program
| Study group | Role | What they receive |
|---|---|---|
| Group I (QuitBot Experimental) | Experimental | Participants participate in the QuitBot program for 42 days to support quitting smoking. QuitBot is a novel chatbot smartphone application for smoking cessation. Receives: Other: Experimental Smoking Cessation Program |
| Group II (SmokefreeTXT Control) | Active comparator | Participants participate in the SmokefreeTXT program for 42 days to support quitting smoking. SmokefreeTXT is a standard of care smoking cessation text messaging program from the NCI. Receives: Other: Control Smoking Cessation Program |
What is being measured
The primary outcome is the main question the study is designed to answer.
Number of Participants With 30-day Cigarette Smoking Cessation
The primary endpoint is 30-day point prevalence abstinence for cigarette smoking at 12 months post-randomization. At 12 months, smoking abstinence is assessed by asking participants: "When was the last time you smoked, or even tried, a cigarette?" Response choices are "Earlier today", "24 hours ago", "2-7 days ago", "8-30 days ago", and "Over 30 days ago". Participants reporting no cigarette consumption in the past 30 days are considered abstinent for the 30-day outcome. Missing outcome data are handled using standard intent-to-treat analysis, with all missing data coded as smoking.
Measured: At 12 months after randomization
Secondary outcomes (1)
Number of Participants With 30-day Cigarette Smoking Cessation
The primary endpoint is 30-day point prevalence abstinence for cigarette smoking at 6 months post-randomization. At 6 months, smoking abstinence is assessed by asking participants: "When was the last time you smoked, or even tried, a cigarette?" Response choices are "Earlier today", "24 hours ago", "2-7 days ago", "8-30 days ago", and "Over 30 days ago". Participants reporting no cigarette consumption in the past 30 days are considered abstinent for the 30-day outcome. Missing outcome data are handled using standard intent-to-treat analysis, with all missing data coded as smoking.
Measured: At 6 months after randomization
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted16 Mar 2020
- Study start24 Jul 2022
- Primary completion1 May 2025
- Study completion8 Apr 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Smoking &Amp; Tobacco CessationStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 1,647 participants (actual)
Sponsor and investigators
- Lead sponsor
- Fred Hutchinson Cancer Center
- Sponsor type
- University, hospital or other
- Collaborators
- National Cancer Institute (NCI)
- Responsible party
- Principal investigator, Jonathan Bricker, Fred Hutchinson Cancer Center
- Investigators
- Jonathan B. Bricker, Principal investigator, Fred Hutch/University of Washington Cancer Consortium
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04308759
- Sponsor's protocol ID
- RG1006844
- Other IDs
- NCI-2020-00136, RG1006844, R01CA247156, 10359
- Status last verified
- May 2026
- First submitted
- 6 Mar 2020
- Last updated
- 22 May 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Bricker JB, Sullivan BM, Mull KE, Lavista-Ferres J, Santiago-Torres M. Efficacy of a conversational chatbot for cigarette smoking cessation: Protocol of the QuitBot full-scale randomized controlled trial. Contemp Clin Trials. 2024 Dec;147:107727. doi: 10.1016/j.cct.2024.107727. Epub 2024 Oct 28.
PubMed 39490766
Study at a glance
From the registry record, last updated by the sponsor on 22 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Full Scale Randomized Trial of an Innovative Conversational Agent for Smoking Cessation (QuitBot)
- ClinicalTrials.gov ID
- NCT04308759
- Acronym / sponsor ID
- RG1006844
- Conditions
- Smoking &Amp; Tobacco Cessation
- Keywords
- Smoking, smoking cessation, quitting smoking, chatbot
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 1,647 participants (actual)
- Lead sponsor
- Fred Hutchinson Cancer CenterUniversity, hospital or other
- Collaborators
- National Cancer Institute (NCI)
- Study start
- 24 Jul 2022 (actual)
- Primary completion
- 1 May 2025 (actual)
- Study completion
- 8 Apr 2026 (actual)
- First posted
- 16 Mar 2020 (actual)
- Results
- Posted 22 May 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This phase III trial compares two remote digital smoking cessation programs to see how well they work for quitting smoking.
Detailed description
OUTLINE:
Participants are randomized to 1 of 2 groups. Both groups receive access to a 42-day quit smoking program.
GROUP I: Experimental QuitBot chatbot program, for 42 days to support quitting smoking. After the completion of study, patients are followed up at 3, 6, and 12 months.
GROUP II: Control SmokefreeTXT text messaging program, for 42 days to support quitting smoking. After the completion of study, patients are followed up at 3, 6, and 12 months.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Group I (QuitBot Experimental) | Experimental | Other: Experimental Smoking Cessation ProgramParticipants participate in the QuitBot program for 42 days to support quitting smoking. QuitBot is a novel chatbot smartphone application for smoking cessation. |
| Group II (SmokefreeTXT Control) | Active comparator | Other: Control Smoking Cessation ProgramParticipants participate in the SmokefreeTXT program for 42 days to support quitting smoking. SmokefreeTXT is a standard of care smoking cessation text messaging program from the NCI. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (11 listed)
- Age 18 or older
- Smokes at least one cigarette a day for the past 12 months
- Wants to quit cigarette smoking within the next 30 days (consistent with text messaging intervention trials)
- If concurrently using any other nicotine or tobacco products, wants to quit using them within the next 30 days
- Interested in learning skills to quit smoking
Key exclusion criteria (1 listed)
- The reverse of the inclusion criteria
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Experimental Smoking Cessation ProgramAlso: ExperimentalParticipate in Quitbot experimental cessation program | Other | Group I (QuitBot Experimental) |
| Control Smoking Cessation ProgramAlso: ControlParticipate in Quitbot control cessation program | Other | Group II (SmokefreeTXT Control) |
Primary outcome
Number of Participants With 30-day Cigarette Smoking Cessation
Time frame: At 12 months after randomization
The primary endpoint is 30-day point prevalence abstinence for cigarette smoking at 12 months post-randomization. At 12 months, smoking abstinence is assessed by asking participants: "When was the last time you smoked, or even tried, a cigarette?" Response choices are "Earlier today", "24 hours ago", "2-7 days ago", "8-30 days ago", and "Over 30 days ago". Participants reporting no cigarette consumption in the past 30 days are considered abstinent for the 30-day outcome. Missing outcome data are handled using standard intent-to-treat analysis, with all missing data coded as smoking.
1 secondary outcome
Number of Participants With 30-day Cigarette Smoking Cessation
Time frame: At 6 months after randomization
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 22 May 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Background: PubMed 39490766Bricker JB, Sullivan BM, Mull KE, Lavista-Ferres J, Santiago-Torres M. Efficacy of a conversational chatbot for cigarette smoking cessation: Protocol of the QuitBot full-scale randomized controlled trial. Contemp Clin Trials. 2024 Dec;147:107727. doi: 10.1016/j.cct.2024.107727. Epub 2024 Oct 28.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Jonathan B. Bricker principal investigator
Fred Hutch/University of Washington Cancer Consortium
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Experimental Smoking Cessation Program in people with Smoking &Amp; Tobacco Cessation, run by Fred Hutchinson Cancer Center at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 11 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 22 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
Yes. Results are posted in the registry (first posted 22 May 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Number of Participants With 30-day Cigarette Smoking Cessation (time frame: At 12 months after randomization). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT04308759, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 22 May 2026.