Post-acute Sequelae of COVID-19Phase 2SHIELDNCT07597902
SARS-CoV-2 and Herpesvirus Inhibition for Ending Long COVID Dysfunction
A Phase 2 study testing Valacyclovir, Celecoxib and Paxlovid in people with Post-acute Sequelae of COVID-19 and Long COVID, run by Icahn School of Medicine at Mount Sinai at 1 site in United States.
Trial summary
The purpose of this research study is to test if the combination of three drugs, valacyclovir, celecoxib, and Paxlovid will decrease the symptoms of Long COVID in adults compared to a placebo (this does not contain the medications). Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Post-acute Sequelae of COVID-19, Long COVID
- What is being tested?
- Valacyclovir, Celecoxib and Paxlovid
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 150 participants
- Where
- 1 siteUnited States
- Study dates
- 20 Oct 2026to 30 Jun 2028
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
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 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 18-65 years of age at the time of study entry
- Diagnosed with Long COVID
- Individuals of child-bearing potential must have a negative serum pregnancy test at screening and agree to on-site urine pregnancy testing at all subsequent study visits
- A urine drug screen performed at the Screening Visit must be negative for drugs of abuse such as methamphetamine, cocaine, phencyclidine (PCP), and non-disclosed amphetamines and opioids/opiates.
- Those with mild to moderate depression should be clinically stable for three months, without risk of suicidal ideation or behavior.
Who cannot join
- Breastfeeding, pregnant, or planning to become pregnant during the next six months.
- In the opinion of the Investigator, any clinically significant, uncontrolled, or unstable medical or surgical condition that could affect the individual's ability to participate in the study or potentially compromise their well-being while enrolled in the study.
- In the opinion of the Investigator or based on results of the HADS, evidence of a clinically significant psychiatric disorder, e.g., severe, unstable or poorly controlled depression, anxiety or obsessive-compulsive disorder; moderate or severe alcohol use disorder; substance use disorder other than mild cannabis use disorder; or any history of bipolar disorder, schizophrenia, schizoaffective disorder or other psychotic disorder.
- Currently meeting criteria for ME/CFS at the pre-screening or screening visit, or a prior confirmed diagnosis of ME/CFS within the last 5 years. This may be determined as part of the initial screening call or visit.
- Any anticipated need for surgery that in the opinion of the Principal Investigator or Sub-I might confound results or interfere with the participant's ability to comply with the protocol.
- Symptomatic and/or otherwise clinically significant cardiac disease
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- Acute non-COVID systemic infection (e.g., HIV, hepatitis) or other active viral or bacterial infection during the screening/washout period or at the Baseline visit.
- Currently receiving chronic systemic corticosteroids (>5 mg prednisone daily, or equivalent)
- Routine treatment with warfarin, heparin, lithium, digoxin, amiodarone, isoniazid, phenytoin, fluconazole, methotrexate, probenecid, or raloxifene. Participants on these medications should not be screened.
- Uncontrolled sleep apnea.
- Use of chronic nucleoside analog antiviral suppression therapy within one month of the Screening Visit or requiring on average more than one acute treatment course every two months.
- Current use of celecoxib either alone or in combination with valacyclovir or famciclovir
- In the opinion of the Investigator, evidence of current drug or alcohol abuse or dependency, or history of abuse or dependence during the preceding 12 months.
- The participant has undergone a malabsorptive weight loss procedure (e.g., Roux-en-Y or other bypass procedure).
- Severe IBS-C or colonic inertia as evidenced by seven or more days between bowel movements.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
The Cohen Center for Recovery from Complex Chronic Illnesses (CoRE)
New York, New York, 10029
CoreResearch@mountsinai.com
David Putrino, PhD
About this study
Official title: SARS-CoV-2 and Herpesvirus Inhibition for Ending Long COVID Dysfunction (SHIELD)
The purpose of this research study is to test if the combination of three drugs, valacyclovir, celecoxib, and Paxlovid will decrease the symptoms of Long COVID in adults compared to a placebo (this does not contain the medications).
Read the detailed description
This is an off-label, randomized, double-blind, active placebo-controlled, two-arm clinical trial of a combination of celecoxib, valacyclovir, and Paxlovid in adults with Long COVID. This study aims to evaluate the safety and efficacy of the combination of celecoxib, valacyclovir, and Paxlovid in adults with Long COVID (LC). Safety will be primarily measured through blood and urine measures. Efficacy will be evaluated by measuring patient-reported outcomes.
- Conditions
- Post-acute Sequelae of COVID-19, Long COVID
- Being tested
- Valacyclovir, Celecoxib, Paxlovid, Placebo
- 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.
ValacyclovirDrug
one to two 750mg capsules taken orally in the morning and evening
CelecoxibDrug
200mg capsules taken orally in the morning and evening
PaxlovidDrug
one (100mg ritonavir tablet and two 150mg nirmatrelvir tablets) taken orally in the morning and evening
PlaceboDrug
matching placebo capsules and tablets taken orally in the morning and evening
| Study group | Role | What they receive |
|---|---|---|
| Combination Drug Therapy | Experimental | For 14 weeks, receives valacyclovir and celecoxib initially, then addition of Paxlovid for 25 days while decreasing valacyclovir dose, and then returns to valacyclovir at the original dose later. Receives: Drug: Valacyclovir; Drug: Celecoxib; Drug: Paxlovid |
| Placebo | Placebo comparator | For 14 weeks, receives matched placebo capsules and tablets Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
EQ-5D-5L Visual Analogue Scale (VAS)
The EQ VAS records the patient's self-rated health on a visual analogue scale where the endpoints are labelled 'The best health you can imagine' (100) and 'The worst health you can imagine' (0), with higher scores indicating better health state. The VAS can be used as a quantitative measure of health outcome that reflects the patient's own judgement.
Measured: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
Secondary outcomes (8)
The EuroQol Five-Dimensional Health Questionnaire (EQ-5D-5L)
The EQ-5D-5L is a validated, standardized, generic instrument that is a preference-based health- related quality of life questionnaire. The descriptive system comprises five dimensions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. Each dimension has 5 levels: no problems, slight problems, moderate problems, severe problems and extreme problems. The patient is asked to indicate their health state by ticking the box next to the most appropriate statement in each of the five dimensions. This decision results in a 1-digit number that expresses the level selected for that dimension. The digits for the five dimensions can be combined into a 5-digit number that describes the patient's health state. Full scale from 5 to 25, with higher score indicating poorer health outcomes.
Measured: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
Patient-Reported Outcomes Measurement Information System 29 (PROMIS-29)
The PROMIS-29 v2.0 profile assesses pain intensity using a single 0-10 numeric rating item and seven health domains (physical function, fatigue, pain interference, depressive symptoms, anxiety, ability to participate in social roles and activities, and sleep disturbance) using four items per domain. The values of all item responses are averaged to generate subscores for each dimension. From these subscores, a global physical health score and a global mental health score are generated. The scores are translated into T-scores according to a reference population with a mean of 50 and a standard deviation of 10.
Measured: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
General Symptom Questionnaire (GSQ-30)
The General Symptom Questionnaire-30 (GSQ-30) is a valid and reliable instrument to assess symptom burden among patients with acute and post-treatment. The GSQ-30 total score ranges from 0 to 120, with higher scores indicating a greater symptom burden.
Measured: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
Patient Health Questionnaire (PHQ-9)
The PHQ-9 is a series of questions assessing presence and severity of depression symptoms. It evaluates each of the DSM-IV depression criteria and scores the responses from 0 ("Not at all") to 3 ("Nearly every day"). PHQ-9 scores of 5, 10, 15, and 20 represented mild, moderate, moderately severe, and severe depression, respectively. Full scale from 0-27, with higher score indicating more severe symptoms.
Measured: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
Generalized Anxiety Disorder (GAD-7)
The GAD-7 is a 7-item scale developed and validated to identify generalized anxiety disorder and its severity. It assesses the frequency of 7 anxiety symptoms and scores the responses from 0 ("Not at all") to 3 ("Nearly every day"). Total scores of 5, 10, and 15 correspond to mild, moderate, and severe generalized anxiety disorder, respectively. Full scale from 0-21, with higher score indicating more symptoms.
Measured: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
COLUMBIA-SUICIDE SEVERITY RATING SCALE (C-SSRS)
A suicide risk assessment tool that supports suicide risk assessment through a series of simple, plain-language questions that anyone can ask. The answers help users identify whether someone is at risk for suicide, assess the severity and immediacy of that risk, and gauge the level of support that the person needs.
Full range from 0 (low intensity suicidal ideation to 9 (high intensity suicidal ideation). Higher score represents poorer health outcomes.
Measured: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
Neuro-QoL™ v2.0 Cognitive Function-Short Form
The Neuro-QoL Cognitive Function v2.0 short form assesses perceived difficulties in cognitive abilities, including memory, attention, decision making, planning, organizing, calculating, remembering, and learning. The short form consists of 8 questions assessed on a 5-point Likert scale, resulting in a raw score range of 8 to 40. A raw score is then converted to a T-score using conversion tables. Scores 0.5 - 1.0 SD worse than the mean (T-score 40-45) = mild symptoms/impairment. Scores 1.0 - 2.0 SD worse than the mean (T-score 30-40) = moderate symptoms/impairment. Scores 2.0 SD or more worse than the mean (T-score below 30) = severe symptoms/impairment.
Measured: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
Single-item Sleep Quality Scale (SQS)
The SQS is a visual analog scale that instructs respondents to rate their overall quality of sleep over a 7-day recall period from 0 to 10. Scores of 0, 1, 4, 7, and 10 correspond to terrible, poor, fair, good, and excellent, respectively. Higher scores indicate better sleep quality.
Measured: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted19 May 2026
- Study start20 Oct 2026
- Primary completion30 Jun 2028 (estimated)
- Study completion30 Jun 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Post-acute Sequelae of COVID-19Studies of the same condition, open and under way.
- More trials run by Icahn School of Medicine at Mount SinaiThe 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
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 150 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Icahn School of Medicine at Mount Sinai
- Sponsor type
- University, hospital or other
- Collaborators
- PridCor Therapeutics
- Responsible party
- Principal investigator, David Putrino, Icahn School of Medicine at Mount Sinai
- Investigators
- David Putrino, PhD, Principal investigator, Icahn School of Medicine at Mount Sinai
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07597902
- Sponsor's protocol ID
- STUDY-25-00948
- Acronym
- SHIELD
- Status last verified
- Aug 2026
- First submitted
- 14 May 2026
- Last updated
- 28 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 28 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- SARS-CoV-2 and Herpesvirus Inhibition for Ending Long COVID Dysfunction (SHIELD)
- ClinicalTrials.gov ID
- NCT07597902
- Acronym / sponsor ID
- SHIELD / STUDY-25-00948
- Conditions
- Post-acute Sequelae of COVID-19, Long COVID
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 150 participants (estimated)
- Lead sponsor
- Icahn School of Medicine at Mount SinaiUniversity, hospital or other
- Collaborators
- PridCor Therapeutics
- Study start
- 20 Oct 2026 (actual)
- Primary completion
- 30 Jun 2028 (estimated)
- Study completion
- 30 Jun 2028 (estimated)
- First posted
- 19 May 2026 (actual)
- Results
- Not posted in the source record
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 research study is to test if the combination of three drugs, valacyclovir, celecoxib, and Paxlovid will decrease the symptoms of Long COVID in adults compared to a placebo (this does not contain the medications).
Detailed description
This is an off-label, randomized, double-blind, active placebo-controlled, two-arm clinical trial of a combination of celecoxib, valacyclovir, and Paxlovid in adults with Long COVID. This study aims to evaluate the safety and efficacy of the combination of celecoxib, valacyclovir, and Paxlovid in adults with Long COVID (LC). Safety will be primarily measured through blood and urine measures. Efficacy will be evaluated by measuring patient-reported outcomes.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Combination Drug Therapy | Experimental | Drug: Valacyclovir, Drug: Celecoxib, Drug: PaxlovidFor 14 weeks, receives valacyclovir and celecoxib initially, then addition of Paxlovid for 25 days while decreasing valacyclovir dose, and then returns to valacyclovir at the original dose later. |
| Placebo | Placebo comparator | Drug: PlaceboFor 14 weeks, receives matched placebo capsules and tablets |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- 18-65 years of age at the time of study entry
- Diagnosed with Long COVID
- Individuals of child-bearing potential must have a negative serum pregnancy test at screening and agree to on-site urine pregnancy testing at all subsequent study visits
- A urine drug screen performed at the Screening Visit must be negative for drugs of abuse such as methamphetamine, cocaine, phencyclidine (PCP), and non-disclosed amphetamines and opioids/opiates.
- Those with mild to moderate depression should be clinically stable for three months, without risk of suicidal ideation or behavior.
Key exclusion criteria (15 listed)
- Breastfeeding, pregnant, or planning to become pregnant during the next six months.
- In the opinion of the Investigator, any clinically significant, uncontrolled, or unstable medical or surgical condition that could affect the individual's ability to participate in the study or potentially compromise their well-being while enrolled in the study.
- In the opinion of the Investigator or based on results of the HADS, evidence of a clinically significant psychiatric disorder, e.g., severe, unstable or poorly controlled depression, anxiety or obsessive-compulsive disorder; moderate or severe alcohol use disorder; substance use disorder other than mild cannabis use disorder; or any history of bipolar disorder, schizophrenia, schizoaffective disorder or other psychotic disorder.
- Currently meeting criteria for ME/CFS at the pre-screening or screening visit, or a prior confirmed diagnosis of ME/CFS within the last 5 years. This may be determined as part of the initial screening call or visit.
- Any anticipated need for surgery that in the opinion of the Principal Investigator or Sub-I might confound results or interfere with the participant's ability to comply with the protocol.
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 |
|---|---|---|
| Valacyclovirone to two 750mg capsules taken orally in the morning and evening | Drug | Combination Drug Therapy |
| Celecoxib200mg capsules taken orally in the morning and evening | Drug | Combination Drug Therapy |
| Paxlovidone (100mg ritonavir tablet and two 150mg nirmatrelvir tablets) taken orally in the morning and evening | Drug | Combination Drug Therapy |
| Placebomatching placebo capsules and tablets taken orally in the morning and evening | Drug | Placebo |
Primary outcome
EQ-5D-5L Visual Analogue Scale (VAS)
Time frame: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
The EQ VAS records the patient's self-rated health on a visual analogue scale where the endpoints are labelled 'The best health you can imagine' (100) and 'The worst health you can imagine' (0), with higher scores indicating better health state. The VAS can be used as a quantitative measure of health outcome that reflects the patient's own judgement.
8 secondary outcomes
The EuroQol Five-Dimensional Health Questionnaire (EQ-5D-5L)
Time frame: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
Patient-Reported Outcomes Measurement Information System 29 (PROMIS-29)
Time frame: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
General Symptom Questionnaire (GSQ-30)
Time frame: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
Patient Health Questionnaire (PHQ-9)
Time frame: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
Generalized Anxiety Disorder (GAD-7)
Time frame: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
COLUMBIA-SUICIDE SEVERITY RATING SCALE (C-SSRS)
Time frame: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
Neuro-QoL™ v2.0 Cognitive Function-Short Form
Time frame: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
Single-item Sleep Quality Scale (SQS)
Time frame: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Oct 2026.
- 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.
David Putrino, PhD principal investigator
Icahn School of Medicine at Mount Sinai
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 Valacyclovir, Celecoxib and Paxlovid in people with Post-acute Sequelae of COVID-19 and Long COVID, run by Icahn School of Medicine at Mount Sinai 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 5 inclusion and 15 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: looking for participants now, as of the sponsor's last update on 28 Oct 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. 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?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact David Putrino, PhD (212-241-7658, CoreResearch@mountsinai.org), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
EQ-5D-5L Visual Analogue Scale (VAS) (time frame: Baseline (Week 1), Week 4, Week 8, Week 12, Week 16, Week 20). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 28 Oct 2026.