Post-acute Sequelae of SARS-CoV-2 InfectionPhase 2STOP-PASCNCT05576662
Paxlovid for Treatment of Long Covid
A Phase 2 study testing Nirmatrelvir and Ritonavir in people with Post-acute Sequelae of SARS-CoV-2 Infection and Long COVID, run by Stanford University at 1 site in United States.
Trial summary
The purpose of this study is to compare whether being treated with nirmatrelvir plus ritonavir for 15 days works better than being treated with placebo plus ritonavir to reduce severe symptoms of Long Covid. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Post-acute Sequelae of SARS-CoV-2 Infection, Long COVID
- What is being tested?
- Nirmatrelvir and Ritonavir
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 168 participants
- Where
- 1 siteUnited States
- Study dates
- 8 Nov 2022to 12 Sep 2023
- Phase
- Phase 2
- 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
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Normal or near-normal kidney function
- History of confirmed COVID-19 infection that preceded the post-COVID symptoms
- Post-COVID-19 symptoms persisting greater than three months
- At least 2 post-COVID symptoms of moderate or severe intensity (fatigue, brain fog, shortness of breath, body aches, gastrointestinal symptoms, or cardiovascular symptoms)
- Willing to report all vaccinations
- Women of childbearing potential or men whose partners may become pregnant must use acceptable method of contraception during the treatment period and for 28 days after the last dose of the study drug
- Willing and able to adhere to study procedures and available for the duration of the study
Who cannot join
- Suspected or confirmed pregnancy or breastfeeding
- Severe liver disease
- Prior use of study drug or other COVID treatment within 30 days
- Hypersensitivity or other contraindication to any components of the study drug
- Current or expected use of any medication dependent on or inducer of CYP3A4
- Current or expected use of supplements or herbs (unless medically necessary) that cannot be temporarily held (period as determined necessary by investigators)
Show all 13Show fewer
- HIV infection with viral load >50 copies/ml
- Suspected or confirmed active COVID infection within 30 days
- History of COVID vaccine within 28 days prior to enrollment, or other vaccine (influenza, shingles, etc.) within 14 days of enrollment, or planned use of any vaccine until the primary endpoint has been met (10 weeks)
- Other medical condition(s) or concomitant therapy that would compromise participant's safety or compliance with the study protocol or significantly confound interpretation of study results, as determined by study investigators
- Current enrollment in, or discontinuation within the last 30 days from, a clinical trial involving any investigational drug or device
- Inability to provide informed consent
- Currently hospitalized
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Selective Trial Of Paxlovid for PASC (STOP-PASC): Randomized Double-Blind Placebo-Controlled Pilot Trial of Paxlovid for the Treatment of PASC
The purpose of this study is to compare whether being treated with nirmatrelvir plus ritonavir for 15 days works better than being treated with placebo plus ritonavir to reduce severe symptoms of Long Covid.
Participants will have 5 planned visits to the study clinic over 15 weeks and will take the drug (or placebo) for the first 15 days.
This study uses the term post-acute sequelae of SARS-CoV-2 (PASC), which is another name for "Long Covid."
Read the detailed description
An exploratory sub-study will investigate the correlation of physical activity and biometric parameters from digital wearable devices with the subjective symptom severity and other patient-reported outcomes in the main study. All participants with iPhone 6S Plus or newer will be offered an opportunity to opt-in to this sub-study. An Apple Watch and Bluetooth-enabled blood pressure monitor will be provided to participants and data will be collected for the duration of the main study to track participants' physiological and behavioral trends in the Paxlovid versus placebo groups.
- Being tested
- Nirmatrelvir, Placebo, Ritonavir
- Medical subject headings
- Post-Acute COVID-19 Syndrome
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
NirmatrelvirDrug
Two 150 mg tablets taken by mouth every 12 hours
PlaceboDrug
Two tablets containing placebo matching nirmatrelvir taken by mouth every 12 hours
RitonavirDrug
One 100 mg capsule taken by mouth every 12 hours
| Study group | Role | What they receive |
|---|---|---|
| Nirmatrelvir plus ritonavir | Experimental | Participants receive nirmatrelvir plus ritonavir (Paxlovid) for 15 days, and attend follow-up visits through week 15. Receives: Drug: Nirmatrelvir; Drug: Ritonavir |
| Placebo plus ritonavir | Placebo comparator | Participants receive placebo to match nirmatrelvir plus ritonavir for 15 days, and attend follow-up visits through week 15. Receives: Drug: Placebo; Drug: Ritonavir |
What is being measured
The primary outcome is the main question the study is designed to answer.
Number of Participants With No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score
This measure was to evaluate whether there is a difference between treatment with Paxlovid versus placebo on any of the 6 core symptoms of PASC at week 10 (adjusting for patients' baseline levels). Each symptom (fatigue, brain fog, dyspnea, body aches, gastrointestinal symptoms, cardiovascular symptoms) was assessed on a 4-point Likert scale (range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms).
Measured: Week 10
Secondary outcomes (17)
Number of Participants With No, Mild, Moderate, or Severe Symptoms at Day 15 According to the Core Symptoms Severity Scale Score
This measure was to evaluate whether there is a difference between treatment with Paxlovid versus placebo on any of the 6 core symptoms of PASC at week 10 (adjusting for patients' baseline levels). Each symptom (fatigue, brain fog, dyspnea, body aches, gastrointestinal symptoms, cardiovascular symptoms) was assessed on a 4-point Likert scale (range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms).
Measured: Day 15
Number of Participants Reporting Relief of at Least One Core Symptom for 2 Weeks
Relief defined as reduction of severity from moderate to none, or severe to mild/none (≥ 2-point Likert score change). Likert score range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms.
Measured: Baseline through week 10, assessed at week 10
Number of Participants With Overall Alleviation for 2 Weeks
Overall alleviation defined as both:
- Any core symptom(s) that are none/mild (Likert 0 or 1) at baseline are none at 10 weeks, and
- Any core symptom(s) that are moderate/severe (Likert 2 or 3) at baseline are none/mild at 10 weeks.
Likert score range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms.
Measured: Baseline through week 10, assessed at week 10
Number of Participants With No, Mild, Moderate, or Severe Symptoms of Their Most Bothersome Symptom
This outcome was to assess the severity of the most bothersome symptom experienced by participants. Each symptom was assessed on a 4-point Likert scale (range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms) using the Core Symptoms Severity Scale.
Measured: Assessed at weeks 5, 10, and 15
Time to Relief of the 6 Core Symptoms
Relief defined as reduction of severity from moderate to none, or severe to mild/none for 2 consecutive weeks (≥ 2-point Likert score change). Likert score range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms.
Measured: Up to 15 weeks
Time to Relief of the Most Bothersome Symptom
Relief defined as reduction of severity from moderate to none, or severe to mild/none for 2 consecutive weeks (≥ 2-point Likert score change). Likert score range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms.
Measured: Up to 15 weeks
Change in Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function T-Score
The PROMIS-Physical Function Short Form (SF) assesses difficulty level performing activities of daily living such as doing chores, climbing stairs, walking, and running errands. The assessment consists of 4 items (questions) with each item scored on 5-point Likert scale (higher scores correspond to better physical function). Scores are computed to a T-score metric, where 50 represents the mean for US general adult population and 10 is the standard deviation. A higher physical function T-score indicates better physical function.
Measured: Baseline and week 10
Change in PROMIS Fatigue T-Score
The PROMIS Fatigue Score assesses level of fatigue and its interference on daily activities. The assessment consists of 7 items (questions) with each item scored on 5-point Likert scale (higher scores correspond to more fatigue). Scores are computed to a T-score metric, where 50 represents the mean for US general adult population and 10 is the standard deviation. A higher fatigue T-score indicates greater fatigue.
Measured: Baseline and week 10
Change in PROMIS Dyspnea-Severity T-Score
The PROMIS-Fatigue Dyspnea-Severity Short Form assesses shortness of breath and its interference on daily activities. The assessment consists of 5 items (questions) scored on 4-point Likert scale with a 7-day recall period (higher scores correspond to worse symptoms). Scores are computed to a T-score metric, where 50 represents the mean for US general adult population and 10 is the standard deviation. A higher Dyspnea-Severity T-score indicates worse symptoms.
Measured: Baseline and week 10
Change in PROMIS Cognitive Function Abilities T-Score
The PROMIS-Cognitive Function Abilities Short Form assesses brain fog and its interference on daily activities. The assessment consists of 4 items scored on 5-point Likert scale with a 7-day recall period (higher scores indicate better cognitive function). Scores are computed to a T-score metric, where 50 represents the mean for US general adult population and 10 is the standard deviation. A higher Cognitive Function T-score indicates better cognitive function.
Measured: Baseline and week 10
Change in Orthostatic Vitals Test
This outcome measures the difference in supine to standing systolic blood pressure (SBP) and diastolic blood pressure (DBP).
Measured: Baseline and week 10
Change in Heart Rate
This outcome measures the difference in supine to standing heart rate.
Measured: Baseline and week 10
Change in 1-minute Sit-to-stand Test
Number of times participant is able to go from sitting (in an armless chair) to standing in 1 minute (sit to stand cycles).
Measured: Baseline and week 10
Patient Global Impression of Severity (PGIS) Scale Score
The PGIS reflects a participant's perception about the overall severity of their disease symptoms, rated from 1 to 6 (1 = not present; 2 = very mild; 3 = mild; 4 = moderate; 5 = severe; 6 = extremely severe).
Measured: Day 15, and weeks 5, 10, and 15
Patient Global Impression of Change (PGIC) Scale Score
The PGIC reflects a participant's perception about the overall efficacy of treatment and their overall status since the start of the treatment, rated from 1 to 7 (1 = very much improved; 2 = much improved; 3 = minimally improved; 4 = no change; 5 = minimally worse; 6 = much worse; 7 = very much worse).
Measured: Day 15, and weeks 5, 10, and 15
Summative Severity Score for All Core Symptoms
Core Symptoms Severity Scale Scores for each of the 6 core symptoms were summed to create a summative score. Each core symptom is assessed on a 4-point Likert scale (range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms). Summative score range: 0 to 18 (high scores correspond to greater severity).
Measured: Weeks 5, 10, and 15
Percentage of Weeks 1-15 With Mild or no Symptoms
Each symptom (fatigue, brain fog, dyspnea, body aches, gastrointestinal symptoms, cardiovascular symptoms) is assessed on a 4-point Likert scale (range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms).
Measured: 15 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted12 Oct 2022
- Study start8 Nov 2022
- Primary completion14 Aug 2023
- Study completion12 Sep 2023
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 (2)Papers the sponsor has linked to this study.
- Other trials for Post-acute Sequelae of SARS-CoV-2 InfectionStudies of the same condition, open and under way.
- More trials run by Stanford UniversityThe sponsor's other registered studies.
- 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 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 168 participants (actual)
Sponsor and investigators
- Lead sponsor
- Stanford University
- Sponsor type
- University, hospital or other
- Collaborators
- Pfizer
- Responsible party
- Sponsor
- Investigators
- Upinder Singh, MD, Principal investigator, Stanford UniversityLinda Geng, MD, PhD, Principal investigator, Stanford University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05576662
- Sponsor's protocol ID
- 66994
- Acronym
- STOP-PASC
- Status last verified
- Aug 2025
- First submitted
- 10 Oct 2022
- Last updated
- 4 Sep 2025
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No: Currently, there is no plan for data sharing.
Publications
Geng LN, Bonilla H, Hedlin H, Jacobson KB, Tian L, Jagannathan P, Yang PC, Subramanian AK, Liang JW, Shen S, Deng Y, Shaw BJ, Botzheim B, Desai M, Pathak D, Jazayeri Y, Thai D, O'Donnell A, Mohaptra S, Leang Z, Reynolds GZM, Brooks EF, Bhatt AS, Shafer RW, Miglis MG, Quach T, Tiwari A, Banerjee A, Lopez RN, De Jesus M, Charnas LR, Utz PJ, Singh U. Nirmatrelvir-Ritonavir and Symptoms in Adults With Postacute Sequelae of SARS-CoV-2 Infection: The STOP-PASC Randomized Clinical Trial. JAMA Intern Med. 2024 Sep 1;184(9):1024-1034. doi: 10.1001/jamainternmed.2024.2007.
PubMed 38848477Gunturkun F, Hedlin H, Botzheim B, Deng Y, Bonilla H, Jagannathan P, Quach TC, Kim S, Lin M, O'Riordan G, Tzeng H, Adamowicz L, Demanuele C, Cai X, Yang PC, Singh U, Geng LN. Digital Biometric Measures in Long COVID: A Secondary Analysis of the STOP-PASC Randomized Clinical Trial. JAMA Netw Open. 2025 Aug 1;8(8):e2526901. doi: 10.1001/jamanetworkopen.2025.26901.
PubMed 40810942
Study at a glance
From the registry record, last updated by the sponsor on 4 Sep 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Selective Trial Of Paxlovid for PASC (STOP-PASC): Randomized Double-Blind Placebo-Controlled Pilot Trial of Paxlovid for the Treatment of PASC
- ClinicalTrials.gov ID
- NCT05576662
- Acronym / sponsor ID
- STOP-PASC / 66994
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 168 participants (actual)
- Lead sponsor
- Stanford UniversityUniversity, hospital or other
- Collaborators
- Pfizer
- Study start
- 8 Nov 2022 (actual)
- Primary completion
- 14 Aug 2023 (actual)
- Study completion
- 12 Sep 2023 (actual)
- First posted
- 12 Oct 2022 (actual)
- Results
- Posted 25 Sep 2024
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this study is to compare whether being treated with nirmatrelvir plus ritonavir for 15 days works better than being treated with placebo plus ritonavir to reduce severe symptoms of Long Covid.
Participants will have 5 planned visits to the study clinic over 15 weeks and will take the drug (or placebo) for the first 15 days.
This study uses the term post-acute sequelae of SARS-CoV-2 (PASC), which is another name for "Long Covid."
Detailed description
An exploratory sub-study will investigate the correlation of physical activity and biometric parameters from digital wearable devices with the subjective symptom severity and other patient-reported outcomes in the main study. All participants with iPhone 6S Plus or newer will be offered an opportunity to opt-in to this sub-study. An Apple Watch and Bluetooth-enabled blood pressure monitor will be provided to participants and data will be collected for the duration of the main study to track participants' physiological and behavioral trends in the Paxlovid versus placebo groups.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, investigator)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Nirmatrelvir plus ritonavir | Experimental | Drug: Nirmatrelvir, Drug: RitonavirParticipants receive nirmatrelvir plus ritonavir (Paxlovid) for 15 days, and attend follow-up visits through week 15. |
| Placebo plus ritonavir | Placebo comparator | Drug: Placebo, Drug: RitonavirParticipants receive placebo to match nirmatrelvir plus ritonavir for 15 days, and attend follow-up visits through week 15. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (7 listed)
- Normal or near-normal kidney function
- History of confirmed COVID-19 infection that preceded the post-COVID symptoms
- Post-COVID-19 symptoms persisting greater than three months
- At least 2 post-COVID symptoms of moderate or severe intensity (fatigue, brain fog, shortness of breath, body aches, gastrointestinal symptoms, or cardiovascular symptoms)
- Willing to report all vaccinations
Key exclusion criteria (13 listed)
- Suspected or confirmed pregnancy or breastfeeding
- Severe liver disease
- Prior use of study drug or other COVID treatment within 30 days
- Hypersensitivity or other contraindication to any components of the study drug
- Current or expected use of any medication dependent on or inducer of CYP3A4
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 |
|---|---|---|
| NirmatrelvirTwo 150 mg tablets taken by mouth every 12 hours | Drug | Nirmatrelvir plus ritonavir |
| PlaceboTwo tablets containing placebo matching nirmatrelvir taken by mouth every 12 hours | Drug | Placebo plus ritonavir |
| RitonavirOne 100 mg capsule taken by mouth every 12 hours | Drug | Nirmatrelvir plus ritonavir, Placebo plus ritonavir |
Primary outcome
Number of Participants With No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score
Time frame: Week 10
This measure was to evaluate whether there is a difference between treatment with Paxlovid versus placebo on any of the 6 core symptoms of PASC at week 10 (adjusting for patients' baseline levels). Each symptom (fatigue, brain fog, dyspnea, body aches, gastrointestinal symptoms, cardiovascular symptoms) was assessed on a 4-point Likert scale (range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms).
17 secondary outcomes
Number of Participants With No, Mild, Moderate, or Severe Symptoms at Day 15 According to the Core Symptoms Severity Scale Score
Time frame: Day 15
Number of Participants Reporting Relief of at Least One Core Symptom for 2 Weeks
Time frame: Baseline through week 10, assessed at week 10
Number of Participants With Overall Alleviation for 2 Weeks
Time frame: Baseline through week 10, assessed at week 10
Number of Participants With No, Mild, Moderate, or Severe Symptoms of Their Most Bothersome Symptom
Time frame: Assessed at weeks 5, 10, and 15
Time to Relief of the 6 Core Symptoms
Time frame: Up to 15 weeks
Time to Relief of the Most Bothersome Symptom
Time frame: Up to 15 weeks
Change in Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function T-Score
Time frame: Baseline and week 10
Change in PROMIS Fatigue T-Score
Time frame: Baseline and week 10
Change in PROMIS Dyspnea-Severity T-Score
Time frame: Baseline and week 10
Change in PROMIS Cognitive Function Abilities T-Score
Time frame: Baseline and week 10
Change in Orthostatic Vitals Test
Time frame: Baseline and week 10
Change in Heart Rate
Time frame: Baseline and week 10
Change in 1-minute Sit-to-stand Test
Time frame: Baseline and week 10
Patient Global Impression of Severity (PGIS) Scale Score
Time frame: Day 15, and weeks 5, 10, and 15
Patient Global Impression of Change (PGIC) Scale Score
Time frame: Day 15, and weeks 5, 10, and 15
Summative Severity Score for All Core Symptoms
Time frame: Weeks 5, 10, and 15
Percentage of Weeks 1-15 With Mild or no Symptoms
Time frame: 15 weeks
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 4 Sep 2025.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Results publication: PubMed 38848477Geng LN, Bonilla H, Hedlin H, Jacobson KB, Tian L, Jagannathan P, Yang PC, Subramanian AK, Liang JW, Shen S, Deng Y, Shaw BJ, Botzheim B, Desai M, Pathak D, Jazayeri Y, Thai D, O'Donnell A, Mohaptra S, Leang Z, Reynolds GZM, Brooks EF, Bhatt AS, Shafer RW, Miglis MG, Quach T, Tiwari A, Banerjee A, Lopez RN, De Jesus M, Charnas LR, Utz PJ, Singh U. Nirmatrelvir-Ritonavir and Symptoms in Adults With Postacute Sequelae of SARS-CoV-2 Infection: The STOP-PASC Randomized Clinical Trial. JAMA Intern Med. 2024 Sep 1;184(9):1024-1034. doi: 10.1001/jamainternmed.2024.2007.
- Results publication: PubMed 40810942Gunturkun F, Hedlin H, Botzheim B, Deng Y, Bonilla H, Jagannathan P, Quach TC, Kim S, Lin M, O'Riordan G, Tzeng H, Adamowicz L, Demanuele C, Cai X, Yang PC, Singh U, Geng LN. Digital Biometric Measures in Long COVID: A Secondary Analysis of the STOP-PASC Randomized Clinical Trial. JAMA Netw Open. 2025 Aug 1;8(8):e2526901. doi: 10.1001/jamanetworkopen.2025.26901.
- Individual participant dataSharing planned: No. Currently, there is no plan for data sharing.
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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.
Upinder Singh, MD principal investigator
Stanford University
Linda Geng, MD, PhD principal investigator
Stanford University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Nirmatrelvir and Ritonavir in people with Post-acute Sequelae of SARS-CoV-2 Infection and Long COVID, run by Stanford University 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 7 inclusion and 13 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 4 Sep 2025. 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. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 25 Sep 2024). 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 No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score (time frame: Week 10). 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 NCT05576662, which also lists 2 linked publications.
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 4 Sep 2025.