Updated May 2026 · ClinicalTrials.gov

RECRUITINGPhase 2INTERVENTIONAL

A Phase 2 Trial Comparing Antiviral Treatments in Early Symptomatic Influenza

Q: Who can participate in NCT05648448?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

Q: How do I contact the trial site for NCT05648448?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Q: Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Q: Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

ADaptive ASsessment of TReatments for influenzA: A Phase 2 Multi-centre Adaptive Randomised Platform Trial to Assess Antiviral Pharmacodynamics in Early Symptomatic Influenza Infection (AD ASTRA)

A Phase 2 Trial Comparing Antiviral Treatments in Early Symptomatic Influenza (NCT05648448) is a Phase 2 interventional studying Influenza and Influenza, Human, sponsored by University of Oxford. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.

About This Trial

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

What Stage of Research Is This?

Phase 2 trials evaluate whether a treatment actually works against Influenza and continue monitoring side effects. Phase 2 enrolls larger groups (typically 100–300 patients) and produces the first real efficacy signal. A successful Phase 2 readout is what unlocks the much larger Phase 3 confirmatory trials needed for FDA approval.

This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.

Target enrollment of 3,000 participants makes this one of the larger Influenza trials currently registered. Trials at this scale are typically global, run across many sites, and designed to generate the definitive evidence package for an FDA approval submission or a label expansion.

Who May Be Eligible (Plain English)

Who May Qualify: - Patient understands the procedures and requirements and is willing and able to give willing to sign a consent form for full participation in the study - Adults, male or female, aged 18 to 60 years at time of consent. - Early symptomatic Influenza (A or B); at least one reported symptom of influenza (including fever, history of fever, myalgias, headache, cough, fatigue, nasal congestion, rhinorrhoea and sore throat) within 4 days (96 hours) - Influenza positive by rapid antigen test OR a positive RT-PCR test for influenza viruses within the last 24hrs with a Ct value of \<30 - Able to walk unaided and unimpeded in activities of daily living (ADLs) - Agrees and is able to adhere to all study procedures, including availability and contact information for follow-up visits Who Should NOT Join This Trial: The patient may not enter the study if ANY of the following apply: - Taking any concomitant medications or drugs which could interact with the study medications or have antiviral activity - Presence of any chronic illness/condition requiring long term treatment or other significant comorbidity - BMI ≥35 Kg/m2 - Clinically relevant laboratory abnormalities discovered at screening - Haemoglobin \<10g/dL - Platelet count \<100,000/uL - ALT \> 2x ULN - Total bilirubin \>1.5 x ULN - eGFR \<70mls/min/1.73m2 - For females: pregnancy, actively trying to become pregnant or lactation (healthy women on OCP are eligible to join) - Contraindication to taking, or known hypersensitivity reaction to any of the proposed therapeutics - Currently participating in another interventional influenza or COVID-19 therapeutic trial - Clinical evidence of pneumonia- e.g. shortness of breath, hypoxaemia, crepitations (imaging not required) - Known to be currently co-infected with SARS-CoV-2 (i.e. confirmed with positive ATK or RT-PCR) - Received live attenuated influenza virus vaccine within 3 weeks prior to study entry Always talk to your doctor about whether this trial is right for you.

These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.

Original Eligibility Criteria

View original clinical language

Inclusion Criteria: * Patient understands the procedures and requirements and is willing and able to give informed consent for full participation in the study * Adults, male or female, aged 18 to 60 years at time of consent. * Early symptomatic Influenza (A or B); at least one reported symptom of influenza (including fever, history of fever, myalgias, headache, cough, fatigue, nasal congestion, rhinorrhoea and sore throat) within 4 days (96 hours) * Influenza positive by rapid antigen test OR a positive RT-PCR test for influenza viruses within the last 24hrs with a Ct value of \<30 * Able to walk unaided and unimpeded in activities of daily living (ADLs) * Agrees and is able to adhere to all study procedures, including availability and contact information for follow-up visits Exclusion Criteria: The patient may not enter the study if ANY of the following apply: * Taking any concomitant medications or drugs which could interact with the study medications or have antiviral activity * Presence of any chronic illness/condition requiring long term treatment or other significant comorbidity * BMI ≥35 Kg/m2 * Clinically relevant laboratory abnormalities discovered at screening * Haemoglobin \<10g/dL * Platelet count \<100,000/uL * ALT \> 2x ULN * Total bilirubin \>1.5 x ULN * eGFR \<70mls/min/1.73m2 * For females: pregnancy, actively trying to become pregnant or lactation (healthy women on OCP are eligible to join) * Contraindication to taking, or known hypersensitivity reaction to any of the proposed therapeutics * Currently participating in another interventional influenza or COVID-19 therapeutic trial * Clinical evidence of pneumonia- e.g. shortness of breath, hypoxaemia, crepitations (imaging not required) * Known to be currently co-infected with SARS-CoV-2 (i.e. confirmed with positive ATK or RT-PCR) * Received live attenuated influenza virus vaccine within 3 weeks prior to study entry

Treatments Being Tested

DRUG

Oseltamivir

Oral oseltamivir 75mg BD for 5/7

DRUG

Favipiravir

Oral favipiravir 1800mg BD D0 and 800mg BD for a further 4/7

DRUG

Zanamivir

Inhaled zanamivir 10mg BD for 5/7

DRUG

Baloxavir

Oral baloxavir: * \<80kg- single dose of 40mg on D0 * ≥80kg- single dose of 80mg on D0

DRUG

Molnupiravir

Oral molnupiravir 800mg BD for 5/7

DRUG

Peramivir

Intravenous peramivir 600mg once only

DRUG

Laninamivir

Inhaled laninamivir 40mg once only

DRUG

Oseltamivir and Baloxavir

Oseltamivir 75mg BD for 5/7 and Baloxavir: * \<80kg- single dose of 40mg on D0 * ≥80kg- single dose of 80mg on D0

DRUG

Oseltamivir and Favipiravir

Oseltamivir 75mg BD for 5/7 and favipiravir 1800mg BD D0 and 800mg BD for a further 4/7

DRUG

Favipiravir and 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

Locations (4)

Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.

Universidade Federal de Minas Gerais

Minas Gerais, Brazil

Laos-Oxford-Mahosot Wellcome Trust Research unit

Vientiane, Laos

Sukraraj Tropical & Infectious Disease Hospital

Kathmandu, Nepal

Faculty of Tropical Medicine, Mahidol University

Bangkok, Thailand

How to Talk to Your Doctor About This Trial

Bring the printable summary of this trial — including the NCT ID (NCT05648448), the sponsor (University of Oxford), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.

Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.

Authoritative Sources

The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.

Frequently Asked Questions

What is the NCT05648448 clinical trial studying?

Who can participate in NCT05648448?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

How do I contact the trial site for NCT05648448?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

How This Page Is Built

Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.

Source: ClinicalTrials.gov API v2 record for NCT05648448. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT05648448. Data: ClinicalTrials.gov."

Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.

Last updated 2026-05-08 · Data from ClinicalTrials.gov.