Influenza PreventionPhase 3NCT07730346
Study to Assess the Prophylactic Efficacy and Safety of Sebaloxavir Marboxil Tablets/Oral Suspension for Influenza Prevention in Household Contacts Aged ≥2 Years.
A Phase 3 study testing Sebaloxavir marboxil in people with Influenza Prevention, run by Nanjing Zenshine Pharmaceuticals at 1 site in China.
Trial summary
This study is a randomized, double-blind, placebo-controlled phase III clinical trial. The trial participants include index participants (IP) and household contacts (HHC). A total of 536 index participants (the first person in the household diagnosed with influenza) and 858 household contacts (family members living… Read more about this study
- Who is it for?
- Ages 2 years and olderHealthy volunteers can take part
- Conditions the study is for
- Influenza Prevention
- What is being tested?
- Sebaloxavir marboxil
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 858 participants
- Where
- 1 siteChina
- Study dates
- 7 Nov 2026to 30 Jan 2028
- Phase
- Phase 3
- 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 2 years and older
- All sexes
- Healthy volunteers accepted
- Child, Adult, Older adult
Who may be able to join
- 1. The index participant (aged ≥18 years), or the index participant (aged <18 years) together with their legal guardian, understands and voluntarily provides written informed consent form (ICF). The index participant must be ≥1 year of age at the time of ICF signing, with no gender restriction.
- 2. The index participant must be the first case of influenza virus infection in the household during the current influenza season.
- 3. The index participant must have a positive result from a rapid influenza diagnostic test (RIDT) or polymerase chain reaction (PCR) assay.
- 4. At the time of HHC randomization, the interval from the onset of the index participant's initial influenza symptoms to informed consent must be ≤48 hours. Symptom onset is defined as: first axillary temperature ≥37.5°C, or the presence of at least one other influenza symptom.
- 5. The index participant must not have used any anti-influenza antiviral medications (including traditional Chinese medicines or Western medicines) since symptom onset, and must be willing to receive oseltamivir phosphate treatment after signing informed consent form.
- 1. Aged ≥2 years at the time of randomization, with no gender restriction;
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- 2. Has been living in the same household with the index participant for at least 48 hours at the time of randomization;
- 3. Is able to reside with the index participant from screening/randomization through Day 10 (must live in the same household with the index participant for at least 7 days);
- 4. Tests negative by rapid influenza diagnostic test (RIDT) or polymerase chain reaction (PCR);
- 5. Meets all of the following criteria and is judged by the investigator to have no influenza virus infection:
- Axillary temperature <37°C at screening;
- No influenza-related symptoms at screening (such as nasal congestion, sore throat, cough, myalgia or arthralgia, fatigue, headache, chills/sweating, or other influenza symptoms assessed by the investigator);
- 6. The HHC is ≥18 years of age, or the HHC is <18 years of age and together with their parent(s)/legal guardian(s) understands and voluntarily signs the informed consent form (ICF), and agrees to comply with all study procedures, including completion of diary cards (the guardian may assist in assessment/completion).
- 7. The HHC must sign the informed consent form (ICF) within 24 hours after the index participant signs the ICF;
- 8. The HHC and their partner must agree to practice complete abstinence or use effective contraceptive measures from screening through 3 months after the end of study drug administration.
Who cannot join
- 1. Participants who are diagnosed with bacterial or other non-influenza virus infections at screening requiring systemic antibacterial or antiviral treatment;
- 2. Participants with suspected hypersensitivity to the active ingredients or excipients of oseltamivir phosphate oral suspension/capsules.
- Household contact:
- 1. Participants with suspected hypersensitivity to the active pharmaceutical ingredients or excipients of the investigational product;
- 2. Participants whose household contacts or other family members (excluding the index participant) have been diagnosed with influenza within 3 months before randomization;
- 3. Participants who have been cohabiting with other family members exhibiting influenza-like symptoms (axillary temperature ≥37.5°C, nasal congestion, sore throat, cough, myalgia/arthralgia, fatigue, headache, chills/sweating, or other influenza symptoms as assessed by the investigator) other than on the screening day;
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- 4. Participants requiring systemic (oral or injectable) or intranasal antipyretic/analgesic agents, corticosteroids, or immunosuppressants (those using topical preparations are allowed);
- 5. Participants who have received an influenza vaccine within 6 months prior to screening;
- 6. Participants who have taken anti-influenza Chinese or Western medications within 30 days prior to screening, including but not limited to neuraminidase inhibitors, hemagglutinin inhibitors, M2 ion channel blockers, cap-dependent endonuclease (CEN) inhibitors, and heat-clearing/detoxifying Chinese herbal medicines, such as oseltamivir, zanamivir, peramivir, laninamivir, umifenovir, favipiravir, rimantadine, amantadine, arbidol, nitazoxanide, baloxavir, Lianhua Qingwen capsules/granules, Jinhua Qinggan granules*, etc.
- 7. Participants with active infection or requiring systemic anti-infective treatment at screening (topical therapy for mild skin infections is allowed).
- 8. Participants with other respiratory viral infections.
- 9. Participants with difficulty swallowing study medication or a history of gastrointestinal disorders that may significantly impair drug absorption, including but not limited to reflux esophagitis, chronic diarrhea, inflammatory bowel disease, intestinal tuberculosis, gastrinoma, short bowel syndrome, or post-gastrectomy.
- 10. Participants with severe underlying comorbidities, defined as Grade 3 or higher per the Common Terminology Criteria for Adverse Events (CTCAE) Version 6.0.
- 11. Immunocompromised participants, including those with malignancies, history of organ or bone marrow transplantation, HIV infection, or use of immunosuppressants within the previous 3 months.
- 12. HHCs requiring long-term use of aspirin- or salicylate-containing products, defined as daily regular use for more than 14 consecutive days.
- 13. Participants with suspected or confirmed alcohol abuse (defined as weekly consumption of >14 units of alcohol; 1 unit = 360 mL beer, 45 mL of 40% spirits, or 150 mL of 12% wine) or history of drug abuse.
- 14. Participants who have participated in another interventional clinical trial of a drug or medical device within 30 days before screening.
- 15. Women who have a positive pregnancy test result or are currently lactating.
- 16. Participants with any other conditions that, in the judgment of the investigator, would preclude enrollment in the study.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
China1 site
China Japan friendship hospital
Beijing, Beijing Municipality, 100029
Dr. Wang, +8618810663558, wwyymm_love@163.com
About this study
Official title: A Multicenter, Randomized, Double-blind, Placebo-controlled Phase III Trial to Assess the Prophylactic Efficacy and Safety of Sebaloxavir Marboxil Tablets/Oral Suspension for Influenza Prevention in Household Contacts Aged ≥2 Years.
This study is a randomized, double-blind, placebo-controlled phase III clinical trial. The trial participants include index participants (IP) and household contacts (HHC). A total of 536 index participants (the first person in the household diagnosed with influenza) and 858 household contacts (family members living with the index participant) are planned to be enrolled. After the index participants and their household contacts have signed informed consent form and passed screening eligibility, randomization will be performed at the household level in a 1:1 ratio, stratifying by the time from onset of the index participant's initial influenza symptoms to signing of informed consent form (<24 hours, ≥24 hours), index participant's viral subtype (influenza A, influenza B), and household contact's age (<12 years, ≥12 years). Household contacts will be assigned to either the Sebaloxavir marboxil group or the placebo group. The study objective is to compare the prophylactic efficacy and safety of Sebaloxavir marboxil tablets/oral suspension versus placebo in household contacts (HHCs).
- Conditions
- Influenza Prevention
- Being tested
- Sebaloxavir marboxil, Placebo
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Sebaloxavir marboxilDrug
Dosing Regimen for Household Contacts:
Sebaloxavir marboxil tablets/oral suspension is administered based on age as follows:
- 18 years: Single dose, Sebaloxavir marboxil tablets: 2 tablets;
- 12 years and <18 years: Single dose, Sebaloxavir marboxil tablets: 1 tablet;
- 2 years and <12 years: Single dose, Sebaloxavir marboxil oral suspension, administered according to body weight.
PlaceboDrug
Dosing Regimen for Household Contacts:
Household contacts will receive the placebo of Sebaloxavir marboxil tablets/oral suspension based on age as follows:
- 18 years: Single dose, placebo of Sebaloxavir marboxil tablets: 2 tablets;
- 12 years and <18 years: Single dose, placebo of Sebaloxavir marboxil tablets: 1 tablet;
- 2 years and <12 years: Single dose, placebo of Sebaloxavir marboxil oral suspension, administered according to body weight.
| Study group | Role | What they receive |
|---|---|---|
| Sebaloxavir marboxil group | Experimental | Not described Receives: Drug: Sebaloxavir marboxil |
| Placebo group | Placebo comparator | Not described Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
The percentage of household contacts (HHCs) with PCR-positive influenza virus infection accompanied by fever (axillary temperature ≥37.5°C) and at least one additional influenza symptom (e.g., nasal congestion, sore throat, cough) after dosing.
Measured: From day1 up to day10
Secondary outcomes (6)
Percentage of HHCs with PCR-positive influenza virus infection but no influenza symptoms after dosing.
Measured: From day1 up to day10
Percentage of HHCs with PCR-positive influenza virus infection accompanied by fever (axillary temperature ≥37.5°C) or at least one other influenza symptom after dosing.
Measured: From day1 up to day10
Time from dosing to PCR-positive influenza virus infection accompanied by fever or at least one other influenza symptom after dosing.
Measured: From day1 up to day10
Time from dosing to meeting the primary endpoint criteria (influenza virus infection accompanied by fever [axillary temperature ≥37.5°C] and at least one other influenza symptom).
Measured: From day1 up to day10
Percentage of households with at least one HHC achieving the primary endpoint criteria after dosing, relative to all households.
Measured: From day1 up to day10
Incidence of all adverse events (AEs) and serious adverse events (SAEs)
Measured: Time Frame: From day1 up to day15
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted28 Jul 2026
- Study start7 Nov 2026 (estimated)
- Primary completion31 Dec 2027 (estimated)
- Study completion30 Jan 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Influenza PreventionStudies 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 3
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind
- Who is masked
- Participant, Care provider, Investigator
- Enrolment
- 858 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Nanjing Zenshine Pharmaceuticals
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07730346
- Sponsor's protocol ID
- ZX-7101A-212
- Status last verified
- Jul 2026
- First submitted
- 23 Jul 2026
- Last updated
- 28 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 28 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Multicenter, Randomized, Double-blind, Placebo-controlled Phase III Trial to Assess the Prophylactic Efficacy and Safety of Sebaloxavir Marboxil Tablets/Oral Suspension for Influenza Prevention in Household Contacts Aged ≥2 Years.
- ClinicalTrials.gov ID
- NCT07730346
- Acronym / sponsor ID
- ZX-7101A-212
- Conditions
- Influenza Prevention
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 858 participants (estimated)
- Lead sponsor
- Nanjing Zenshine PharmaceuticalsIndustry (pharma, biotech, devices)
- Study start
- 7 Nov 2026 (estimated)
- Primary completion
- 31 Dec 2027 (estimated)
- Study completion
- 30 Jan 2028 (estimated)
- First posted
- 28 Jul 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.
This study is a randomized, double-blind, placebo-controlled phase III clinical trial. The trial participants include index participants (IP) and household contacts (HHC). A total of 536 index participants (the first person in the household diagnosed with influenza) and 858 household contacts (family members living with the index participant) are planned to be enrolled. After the index participants and their household contacts have signed informed consent form and passed screening eligibility, randomization will be performed at the household level in a 1:1 ratio, stratifying by the time from onset of the index participant's initial influenza symptoms to signing of informed consent form (<24 hours, ≥24 hours), index participant's viral subtype (influenza A, influenza B), and household contact's age (<12 years, ≥12 years). Household contacts will be assigned to either the Sebaloxavir marboxil group or the placebo group. The study objective is to compare the prophylactic efficacy and safety of Sebaloxavir marboxil tablets/oral suspension versus placebo in household contacts (HHCs).
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, care provider, investigator)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Sebaloxavir marboxil group | Experimental | Drug: Sebaloxavir marboxil |
| Placebo group | Placebo comparator | Drug: Placebo |
Who may qualify
- Ages
- 2 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Child, Adult, Older adult
Key inclusion criteria (15 listed)
- 1. The index participant (aged ≥18 years), or the index participant (aged <18 years) together with their legal guardian, understands and voluntarily provides written informed consent form (ICF). The index participant must be ≥1 year of age at the time of ICF signing, with no gender restriction.
- 2. The index participant must be the first case of influenza virus infection in the household during the current influenza season.
- 3. The index participant must have a positive result from a rapid influenza diagnostic test (RIDT) or polymerase chain reaction (PCR) assay.
- 4. At the time of HHC randomization, the interval from the onset of the index participant's initial influenza symptoms to informed consent must be ≤48 hours. Symptom onset is defined as: first axillary temperature ≥37.5°C, or the presence of at least one other influenza symptom.
- 5. The index participant must not have used any anti-influenza antiviral medications (including traditional Chinese medicines or Western medicines) since symptom onset, and must be willing to receive oseltamivir phosphate treatment after signing informed consent form.
Key exclusion criteria (19 listed)
- 1. Participants who are diagnosed with bacterial or other non-influenza virus infections at screening requiring systemic antibacterial or antiviral treatment;
- 2. Participants with suspected hypersensitivity to the active ingredients or excipients of oseltamivir phosphate oral suspension/capsules.
- 1. Participants with suspected hypersensitivity to the active pharmaceutical ingredients or excipients of the investigational product;
- 2. Participants whose household contacts or other family members (excluding the index participant) have been diagnosed with influenza within 3 months before randomization;
- 3. Participants who have been cohabiting with other family members exhibiting influenza-like symptoms (axillary temperature ≥37.5°C, nasal congestion, sore throat, cough, myalgia/arthralgia, fatigue, headache, chills/sweating, or other influenza symptoms as assessed by the investigator) other than on the screening day;
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 |
|---|---|---|
| Sebaloxavir marboxilDosing Regimen for Household Contacts: Sebaloxavir marboxil tablets/oral suspension is administered based on age as follows: * 18 years: Single dose, Sebaloxavir marboxil tablets: 2 tablets; * 12 years and <18 years: Single dose, Sebaloxavir marboxil tablets: 1 tablet; * 2 years and <12 years: Single dose, Sebaloxavir marboxil oral suspension, administered according to body weight. | Drug | Sebaloxavir marboxil group |
| PlaceboDosing Regimen for Household Contacts: Household contacts will receive the placebo of Sebaloxavir marboxil tablets/oral suspension based on age as follows: * 18 years: Single dose, placebo of Sebaloxavir marboxil tablets: 2 tablets; * 12 years and <18 years: Single dose, placebo of Sebaloxavir marboxil tablets: 1 tablet; * 2 years and <12 years: Single dose, placebo of Sebaloxavir marboxil oral suspension, administered according to body weight. | Drug | Placebo group |
Primary outcome
The percentage of household contacts (HHCs) with PCR-positive influenza virus infection accompanied by fever (axillary temperature ≥37.5°C) and at least one additional influenza symptom (e.g., nasal congestion, sore throat, cough) after dosing.
Time frame: From day1 up to day10
6 secondary outcomes
Percentage of HHCs with PCR-positive influenza virus infection but no influenza symptoms after dosing.
Time frame: From day1 up to day10
Percentage of HHCs with PCR-positive influenza virus infection accompanied by fever (axillary temperature ≥37.5°C) or at least one other influenza symptom after dosing.
Time frame: From day1 up to day10
Time from dosing to PCR-positive influenza virus infection accompanied by fever or at least one other influenza symptom after dosing.
Time frame: From day1 up to day10
Time from dosing to meeting the primary endpoint criteria (influenza virus infection accompanied by fever [axillary temperature ≥37.5°C] and at least one other influenza symptom).
Time frame: From day1 up to day10
Percentage of households with at least one HHC achieving the primary endpoint criteria after dosing, relative to all households.
Time frame: From day1 up to day10
Incidence of all adverse events (AEs) and serious adverse events (SAEs)
Time frame: Time Frame: From day1 up to day15
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 Jul 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.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing Sebaloxavir marboxil in people with Influenza Prevention, run by Nanjing Zenshine Pharmaceuticals at 1 site in China.
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 15 inclusion and 19 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: opening soon, as of the sponsor's last update on 28 Jul 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 China. 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 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
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?
Each site lists its own contact: choose the nearest one under Trial locations. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
The percentage of household contacts (HHCs) with PCR-positive influenza virus infection accompanied by fever (axillary temperature ≥37.5°C) and at least one additional influenza symptom (e.g., nasal congestion, sore throat, cough) after dosing. (time frame: From day1 up to day10). 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 Jul 2026.