NorovirusPhase 1/2NCT07198139
A Study to Evaluate the Efficacy, Safety and Pharmacokinetics of CDI-988 in Healthy Adults After Challenge With Snow Mountain Virus
A Phase 1/2 study testing CDI-988 and Snow Mountain Virus in people with Norovirus, run by Cocrystal Pharma, Inc. at 1 site in United States.
Trial summary
Participants in this study will be given either CDI-988 or placebo orally before receiving a norovirus challenge virus and continuing for 5 days. Participants will not know whether they are getting placebo or CDI-988. Read more about this study
- Who is it for?
- Ages 18 to 49 yearsHealthy volunteers can take part
- Conditions the study is for
- Norovirus
- What is being tested?
- CDI-988 and Snow Mountain Virus
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 32 participants
- Where
- 1 siteUnited States
- Study dates
- 23 Feb 2026to 14 Sep 2026
- Phase
- Phase 1/2
- Are there results?
- None posted in the registry
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 49 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Healthy male or non-pregnant female
- Aged 18 to 49 years
- Good state of health
- Known fucosyl transferase 2 (FUT2) secretor status
Who cannot join
- History of participation in any norovirus challenge or vaccine clinical trial
- Receipt or planned receipt of any non-live vaccines within 7 days or live vaccines within 30 days before screening or prior to Day 28
- History of suspected norovirus gastroenteritis or chronic/recurrent gastrointestinal symptoms (e.g., diarrhea or vomiting) within 2 years prior to screening
- History of diagnosed gastrointestinal malabsorption disorders, major gastrointestinal surgery, or diagnosed chronic GI conditions
- Presence of moderate or severe illness, fever (≥38°C), or diarrhea/vomiting within 7 days prior to challenge
- Any acute illness on Day 1 (dosing day)
Show all 10Show fewer
- Positive Day 0 stool tests for enteric pathogens
- Body weight <45 kg or BMI <18 or >32 kg/m² on Day 0
- Use of immunosuppressive therapy within 6 months prior to Day 0 or having any primary or secondary immunocompromising condition
- Use of high-dose systemic corticosteroids (≥20 mg/day prednisolone for ≥2 weeks) or high-dose inhaled steroids for >7 days within 6 months
Trial locations and contacts
1 site in 1 country.
United States1 site
Hope Clinic of the Emory Vaccine Center
Decatur, Georgia, 30030
About this study
Official title: A Phase 1b, Randomized, Double-blind, Placebo-controlled Trial to Evaluate the Efficacy, Safety and Pharmacokinetics of CDI-988 in Healthy Adults After Challenge With Norovirus
Participants in this study will be given either CDI-988 or placebo orally before receiving a norovirus challenge virus and continuing for 5 days. Participants will not know whether they are getting placebo or CDI-988. The study will evaluate how well CDI-988 compared to placebo can reduce the incidence of clinical symptoms after a challenge with norovirus. The amount of virus in stool samples will be measured over time. Side effects and pharmacokinetics (the amount of CDI-988 in blood) will also be measured.
Read the detailed description
This is a single center Phase 1b randomized, double-blind, placebo-controlled study. The primary objective will be to evaluate the efficacy of CDI-988 in comparison to placebo in reducing the incidence of clinical symptoms after challenge with norovirus. Secondary objectives will be to evaluate the efficacy of CDI-988 in comparison to placebo in reducing viral shedding and disease severity and to evaluate the safety of CDI-988 in comparison to placebo.
- Conditions
- Norovirus
- Being tested
- CDI-988, Placebo, Snow Mountain Virus
- Keywords
- tolerability, viral challenge model, antiviral
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
CDI-988Drug
Antiviral to treat norovirus
PlaceboDrug
Matching placebo
Snow Mountain VirusOther
Challenge with Snow Mountain Virus
| Study group | Role | What they receive |
|---|---|---|
| Snow Mountain Virus | Other | Challenge with Snow Mountain Virus Receives: Other: Snow Mountain Virus |
| Stage 2: Drug CDI-988 | Experimental | Not described Receives: Drug: CDI-988; Other: Snow Mountain Virus |
| Stage 2: Placebo | Placebo comparator | Not described Receives: Drug: Placebo; Other: Snow Mountain Virus |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence of norovirus-confirmed disease
Disease is defined as diarrhea and/or vomiting (during the inpatient period), with laboratory-confirmed infection (with SMV specific primers on stool/emesis) or seroconversion
Measured: Day 0 to Day 21
Secondary outcomes (9)
Modified Vesikari Score (MVS) symptom scores during the inpatient period in infected patients
Score based on duration of diarrhea, maximum number of stools in a 24 hour period, duration of vomiting and maximum number of vomiting episodes in a 24 hour period
Measured: Day 1 to Day 6
Time to symptom improvement
From peak Total Symptom Score to point where Total Symptom Score is within 3 points of baseline prior to challenge. The Modified Vesikari Score is a clinical tool used to assess the severity of acute gastroenteritis in children. The minimum and maximum values are 0 and 20, respectively. Higher scores mean a worse clinical severity. For example, a higher score reflects more severe symptoms such as longer duration or higher frequency of diarrhea or vomiting.
Measured: Day 1 to Day 6
Time to first SMV-negative stool
Determined by RT-qPCR
Measured: Day 1 to Day 6
Area Under the Curve of SMV load
Determined by RT-qPCR
Measured: Day 1 to Day 21
Incidence of treatment emergent adverse events
Number of participants with adverse events following first dose
Measured: Day 0 to Day 21
Incidence of serious adverse events
Number of participants with serious adverse events
Measured: From signing informed consent to Day 21
Maximum plasma concentration of CDI-988
Amount of CDI-988 in the blood
Measured: Day 0 and Day 4 pre-dose and at 2, 3, 4, 6, 8, and 12 hours
Time of maximum plasma concentration of CDI-988
time to reach maximum plasma concentration
Measured: Day 0 and Day 4 pre-dose and at 2, 3, 4, 6, 8, and 12 hours
Area under the plasma concentration time curve
Measurement of area under the plasma concentration-time curve (AUC)
Measured: Day 0 and Day 4 pre-dose and at 2, 3, 4, 6, 8, and 12 hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Sep 2025
- Study start23 Feb 2026
- Primary completion14 Sep 2026
- Study completion14 Sep 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for NorovirusStudies 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 1/2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 32 participants (actual)
Sponsor and investigators
- Lead sponsor
- Cocrystal Pharma, Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Nadine Rouphael, MD, Principal investigator, Hope Clinic of the Emory Vaccine Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07198139
- Sponsor's protocol ID
- CDI-988-P1b-001
- Status last verified
- Oct 2026
- First submitted
- 15 Sep 2025
- Last updated
- 22 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No: Only aggregate participant data will be available from this study
Study at a glance
From the registry record, last updated by the sponsor on 22 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 1b, Randomized, Double-blind, Placebo-controlled Trial to Evaluate the Efficacy, Safety and Pharmacokinetics of CDI-988 in Healthy Adults After Challenge With Norovirus
- ClinicalTrials.gov ID
- NCT07198139
- Acronym / sponsor ID
- CDI-988-P1b-001
- Conditions
- Norovirus
- Keywords
- tolerability, viral challenge model, antiviral
- Phase
- Phase 1/2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 32 participants (actual)
- Lead sponsor
- Cocrystal Pharma, Inc.Industry (pharma, biotech, devices)
- Study start
- 23 Feb 2026 (actual)
- Primary completion
- 14 Sep 2026 (actual)
- Study completion
- 14 Sep 2026 (actual)
- First posted
- 30 Sep 2025 (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.
Participants in this study will be given either CDI-988 or placebo orally before receiving a norovirus challenge virus and continuing for 5 days. Participants will not know whether they are getting placebo or CDI-988. The study will evaluate how well CDI-988 compared to placebo can reduce the incidence of clinical symptoms after a challenge with norovirus. The amount of virus in stool samples will be measured over time. Side effects and pharmacokinetics (the amount of CDI-988 in blood) will also be measured.
Detailed description
This is a single center Phase 1b randomized, double-blind, placebo-controlled study. The primary objective will be to evaluate the efficacy of CDI-988 in comparison to placebo in reducing the incidence of clinical symptoms after challenge with norovirus. Secondary objectives will be to evaluate the efficacy of CDI-988 in comparison to placebo in reducing viral shedding and disease severity and to evaluate the safety of CDI-988 in comparison to placebo.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Snow Mountain Virus | Other | Other: Snow Mountain VirusChallenge with Snow Mountain Virus |
| Stage 2: Drug CDI-988 | Experimental | Drug: CDI-988, Other: Snow Mountain Virus |
| Stage 2: Placebo | Placebo comparator | Drug: Placebo, Other: Snow Mountain Virus |
Who may qualify
- Ages
- 18 to 49 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (4 listed)
- Healthy male or non-pregnant female
- Aged 18 to 49 years
- Good state of health
- Known fucosyl transferase 2 (FUT2) secretor status
Key exclusion criteria (10 listed)
- History of participation in any norovirus challenge or vaccine clinical trial
- Receipt or planned receipt of any non-live vaccines within 7 days or live vaccines within 30 days before screening or prior to Day 28
- History of suspected norovirus gastroenteritis or chronic/recurrent gastrointestinal symptoms (e.g., diarrhea or vomiting) within 2 years prior to screening
- History of diagnosed gastrointestinal malabsorption disorders, major gastrointestinal surgery, or diagnosed chronic GI conditions
- Presence of moderate or severe illness, fever (≥38°C), or diarrhea/vomiting within 7 days prior to challenge
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 |
|---|---|---|
| CDI-988Antiviral to treat norovirus | Drug | Stage 2: Drug CDI-988 |
| PlaceboMatching placebo | Drug | Stage 2: Placebo |
| Snow Mountain VirusChallenge with Snow Mountain Virus | Other | Snow Mountain Virus, Stage 2: Drug CDI-988, Stage 2: Placebo |
Primary outcome
Incidence of norovirus-confirmed disease
Time frame: Day 0 to Day 21
Disease is defined as diarrhea and/or vomiting (during the inpatient period), with laboratory-confirmed infection (with SMV specific primers on stool/emesis) or seroconversion
9 secondary outcomes
Modified Vesikari Score (MVS) symptom scores during the inpatient period in infected patients
Time frame: Day 1 to Day 6
Time to symptom improvement
Time frame: Day 1 to Day 6
Time to first SMV-negative stool
Time frame: Day 1 to Day 6
Area Under the Curve of SMV load
Time frame: Day 1 to Day 21
Incidence of treatment emergent adverse events
Time frame: Day 0 to Day 21
Incidence of serious adverse events
Time frame: From signing informed consent to Day 21
Maximum plasma concentration of CDI-988
Time frame: Day 0 and Day 4 pre-dose and at 2, 3, 4, 6, 8, and 12 hours
Time of maximum plasma concentration of CDI-988
Time frame: Day 0 and Day 4 pre-dose and at 2, 3, 4, 6, 8, and 12 hours
Area under the plasma concentration time curve
Time frame: Day 0 and Day 4 pre-dose and at 2, 3, 4, 6, 8, and 12 hours
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 22 Oct 2026.
- Individual participant dataSharing planned: No. Only aggregate participant data will be available from this study
Related trials for Norovirus
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NOV-ERA - A Clinical Trial to Assess the Efficacy and Safety of Ontunisertib Compared to Placebo in Patients With Fibrostenosing Crohn's Disease
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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.
Nadine Rouphael, MD principal investigator
Hope Clinic of the Emory Vaccine Center
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1/2 study testing CDI-988 and Snow Mountain Virus in people with Norovirus, run by Cocrystal Pharma, Inc. 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 4 inclusion and 10 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 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 combined phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
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?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
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?
Incidence of norovirus-confirmed disease (time frame: Day 0 to Day 21). 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 22 Oct 2026.