A Phase 2 interventional study of Oseltamivir and Favipiravir in Influenza and Influenza, Human, sponsored by University of Oxford. Recruiting at 4 sites in 4 countries. Open to participants aged 18 Years to 60 Years. Per ClinicalTrials.gov, last updated 2026-04-14.
Sponsored by University of Oxford · Phase 2, Interventional, and Treatment
Among 59 studies testing oseltamivir in Influenza, Human — 3 open to participants now, 5 under way, 3 of them phase 3. Oseltamivir · Influenza, Human.
Among the 59 studies testing oseltamivir in Influenza, Human, this one has the largest planned enrollment of the 58 interventional ones, is one of 2 that started in 2023, is one of 12 in phase 2, and was the 56th registered.
2,356 studies on the registry are indexed under Influenza, Human; 184 are open to participants now.
This study's planned enrollment of 3,000 is above the median of 227 across 1,957 interventional studies indexed under Influenza, Human.
Browse Influenza, Human studies →3 of the 59 studies testing oseltamivir in Influenza, Human are open now, in 5 countries. Each count lists the studies.
Oseltamivir: first FDA approval 1999 (TAMIFLU), first EMA approval 2002. What it is approved for, and how studies give it, is on its page →
Of the 119 Influenza, Human studies recruiting now, 62 (52%) set no upper age limit and 47 (39%) stop at 75 or younger; 31 take children under 18; 65 take healthy volunteers.
This study: 18 Years to 60 Years · all sexes · no healthy volunteers.
The full table on the hub →59 studies; the count open now beside each. This study's row is marked.
First in 2005; this study’s year is marked. 2 started in 2023.
Median enrollment 118 across the 58 interventional studies. Of the 44 that completed or were terminated, 20 (45%) have results posted.
21 of 59 have an industry lead sponsor. The 10 most frequent:
University of Oxford is the lead sponsor of 812 studies on the registry; 119 are open to participants now.
13 studies in Influenza, Human by University of Oxford: 1 open now, 1 under way, none of them phase 3. Of 11 finished, 0 (0%) have results posted.
Among the 13 studies in Influenza, Human by University of Oxford, this one has the largest planned enrollment of the 12 interventional ones, is the only one that started in 2023, is one of 5 in phase 2, and was the 13th registered.
University of Oxford’s Influenza, Human studies by the year they started, since 2008.
2 of the studies testing oseltamivir in Influenza, Human that are under way reach primary completion within a year, 1 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT07236814Phase 3Capital Medical UniversitySuraxavir Marboxil And Oseltamivir for Influenza Prophylaxis Under a Hospital-based Setting | 2027-03-01 |
| NCT05648448University of OxfordA Phase 2 Trial Comparing Antiviral Treatments in Early Symptomatic Influenza | 2027-01-01 |
Among the 59 studies testing oseltamivir in Influenza, Human, from their registry updates:
Among University of Oxford’s 13 in Influenza, Human:
Nothing recorded among them since 2026-09-25.
This trial will use a previously validated platform, to quantitatively assess antiviral effects in low-risk patients with high viral burdens and uncomplicated influenza, to determine in-vivo antiviral activity. In this randomised, open-label, controlled, group sequential, adaptive, platform trial, we will compare the performance of available influenza antivirals, and those with potential activity, relative to the control (no treatment) and each other.
AD ASTRA study is supported by the Wellcome Trust Grant ref: 223195/Z/21/Z through the COVID-19 Therapeutics Accelerator
Several influenza antivirals are licensed, differing in availability and routes of administration. Direct comparisons of antiviral and clinical efficacy between the multiple available antivirals are lacking. This comparative information is important for guideline development and for aiding purchasing and prioritisation decisions with several options available.
The platform trial will assess the following interventions:
Randomisation to the no antiviral treatment control arm (no intervention) will be fixed at a minimum of 20% throughout the study. The randomisation ratios will be uniform for all available interventions.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
The patient may not enter the study if ANY of the following apply:
laboratory abnormalities discovered at screening
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Drug: Oseltamivir
Drug: Favipiravir
Drug: Zanamivir
Drug: Baloxavir
Drug: Molnupiravir
Drug: Peramivir
Drug: Laninamivir
Drug: Oseltamivir and Baloxavir
Drug: Oseltamivir and Favipiravir
Drug: Favipiravir and Baloxavir
No treatment (except antipyretics- paracetamol)
Oral oseltamivir 75mg BD for 5/7
Oral favipiravir 1800mg BD D0 and 800mg BD for a further 4/7
Inhaled zanamivir 10mg BD for 5/7
Oral baloxavir: * \<80kg- single dose of 40mg on D0 * ≥80kg- single dose of 80mg on D0
Oral molnupiravir 800mg BD for 5/7
Intravenous peramivir 600mg once only
Inhaled laninamivir 40mg once only
Drug pages: Oseltamivir · Baloxavir
Oseltamivir 75mg BD for 5/7 and Baloxavir: * \<80kg- single dose of 40mg on D0 * ≥80kg- single dose of 80mg on D0
Drug pages: Oseltamivir · Favipiravir
Oseltamivir 75mg BD for 5/7 and favipiravir 1800mg BD D0 and 800mg BD for a further 4/7
Drug pages: Favipiravir · Baloxavir
favipiravir 1800mg BD D0 and 800mg BD for a further 4/7 Baloxavir: * \<80kg- single dose of 40mg on D0 * ≥80kg- single dose of 80mg on D0
Rate of viral clearance for currently available drugs and those with potential activity
Rate of viral clearance- estimated from the log10 viral density derived from qPCR of standardised duplicate oropharyngeal swabs/saliva taken daily from baseline (day 0) to day 7 for each therapeutic arm compared with the no antiviral treatment control i.e. those not receiving study drug
Time frame: Days 0 - 5
Rate of viral clearance in early influenza infection
Rate of viral clearance in early influenza infection to characterise the determinants of viral clearance in early influenza infection e.g. contribution of baseline serology, influenza type/subtype, prior vaccination
Time frame: Days 0 - 5
Rate of viral clearance for drugs shown to have considerable antiviral activity
Rate of viral clearance for drugs to determine optimal dosing regimens for drugs shown to have considerable antiviral activity
Time frame: Days 0 - 5
Time to symptom alleviation and fever duration
Assessment of time to symptom alleviation and fever duration to compare time to symptom resolution and fever duration between interventions
Time frame: Days 0 - 14
Rates of hospitalisation for clinical trial reasons
Rates of hospitalisation for clinical reasons up to day 28
Time frame: Days 0 - 28
Development of influenza-related complications
Development of influenza-related complications including bronchitis, sinusitis, otitis media and pneumonia requiring antibiotics, up to day 28
Time frame: Days 0 - 28
7. Relationship between viral clearance, randomisation arm and other measures (covariates) and development of symptoms or functional issues following illness with influenza.
This will be scored using the Modified Influenza Yorkshire Rehabilitation Scale (Flu-YRSm), adapted from the Modified COVID-19 Yorkshire Rehabilitation Scale (C19-YRSm).
Time frame: Days 0-120
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: Yes — With patient's consent, clinical data and results from blood analyses stored in the database may be shared according to the terms defined in the MORU data sharing policy with other researchers to use in the future. https://wellcome.ac.uk/press-release/statement-data-sharing-public-health-emergencies). The data generated in this study belongs to the study group as a whole. The final database will be shared amongst the site PI and key members of the research team. The database may be shared with researchers not directly involved in this study after the main paper has been published and in accordance with MORU guidelines on data sharing.
Access criteria: Refer to MORU data sharing policy with other researchers to use in the future. https://wellcome.ac.uk/press-release/statement-data-sharing-public-health-emergencies).
Data sharing details ↗ · wellcome.ac.uk
Started Feb 2023 (actual). Primary completion is estimated for Jan 2027, 46 months after the start.
Of 36 non-industry phase 2 interventional studies under Influenza, Human, half reached primary completion within 19 months of starting (the median), counting those still running; a quarter within 9 and three quarters within 56. This study's planned 46 months is above that.
Counting every sponsor, half of 122 studies reached it within 10 months; a quarter within 5 and three quarters within 19.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
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Studies of the drugs tested here: Oseltamivir · Favipiravir · Zanamivir · Baloxavir · Molnupiravir · Peramivir · Laninamivir