At a glance
- What the study gets you
- Access to the study treatment being tested
- Type of study
- Interventional (receives a drug or procedure)
- Time in hospital
- In-person visits at study sites — visit count not specified by the sponsor
- Drug or intervention
- MK-1406 (combination product), Placebo (combination product)
- How long the study runs
- Study runs about 21 months (dates as stated)
- About the drug or intervention
- MK-1406 — combination product: MK-1406 liquid for injection administered subcutaneously (SC) · Placebo — combination product: MK-1406 matched liquid for SC injection
- Patient visit burden
- Not specified by the sponsor
- Type of study
- Testing a treatment
- Ages
- 12 Years and over
- Who
- All
- Number of participants
- 10,000
- Started
- 2025-09-25
- Last checked
- 2026-09
Plain English Summary
What is this study?
- • Testing a new treatment for influenza
- • Phase3 - 10,000 participants
- • Approximately one billion cases of seasonal influenza occur annually
Who can take part?
- • Ages 12 Years and over
- • Diagnosed with influenza
Where?
- • Aberdeen - Aberdeen Royal Infirmary ( Site 0423)
- • Bristol - Southmead Hospital ( Site 0409)
- • Bristol - Velocity Clinical Research, Bristol ( Site 0428)
- • High Wycombe - Velocity Clinical Research High Wycombe ( Site 0406)
- • +56 more UK sites
This is a simplified summary. Always discuss with your doctor before making any decisions.
About This Trial
Approximately one billion cases of seasonal influenza occur annually. Of these, 3 to 5 million illnesses are severe and responsible for up to 650,000 deaths per year (WHO 2025). Yearly administration of an influenza vaccine for the prevention of influenza is currently recommended. However, the real-world vaccine effectiveness varied from 10% to 60% in the general population across the years of 2004 to 2024, with effectiveness in most years below 50% (CDC 2025) and decreasing to as low as 5% in immunocompromised individuals (Hughes 2021). The goal of this study is to learn whether MK-1406 (CD388) can help prevent the flu in people who are at higher risk of becoming seriously ill from influenza. Researchers want to find out if MK-1406 dosed at a single study visit can provide protection against influenza compared with placebo. The study will include adolescents and adults who may be more vulnerable to complications from influenza because of their age, health conditions, or weakened immune systems. Researchers will also evaluate the safety of MK-1406 and how well participants tolerate the study medicine.
More detail
This is a Phase 3, randomized, double-blind, placebo-controlled, parallel-group, multicenter study to evaluate the efficacy, safety, and tolerability of MK-1406 (CD388) administered as a single dose via 3 subcutaneous (SC) injections in adult and adolescent participants who are at higher risk of developing complications from influenza.
How this trial compares with your answers
Answer 2 more questions to improve match
What we know so far
Still need:
- • Tell us your age for better matching
- • Tell us your sex for better matching
Preliminary match based on your answers. Full eligibility requires on-site assessment including medical history, physical exam, and lab tests. This does not guarantee enrolment.
Eligibility at a Glance
Key info
- Age: 12 Years and over
- Who can join: All genders
Biomarkers mentioned
What the study is looking for
- ✓The main inclusion criteria include but are not limited to the following:
- ✓Has negative rapid antigen tests for influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)...
- ✓Weight is ≥ 40 kg
- ✓Primary Stratum A only
- ✓Has a history of lung disease
Who cannot take part
- ✗The main exclusion criteria include but are not limited to the following:
- ✗Has an acute (time-limited) or febrile (temperature ≥ 38.0°C \[≥ 100.4°F\]) illness within 7 days prior to planned...
- ✗Has severe chronic kidney disease (CKD) or is receiving hemodialysis
- ✗Receipt within the past 30 days or 5 half-lives (whichever is longer) or anticipated receipt of any drug or other...
- ✗Has previously enrolled in this study (CD388.SQ.3.06)
See the full criteria
Where Is This Study? (60 UK sites)
Aberdeen Royal Infirmary ( Site 0423)
Aberdeen AB252ZN, United Kingdom
Southmead Hospital ( Site 0409)
Bristol BS10 5NB, United Kingdom
Velocity Clinical Research, Bristol ( Site 0428)
Bristol BS8 2RA, United Kingdom
Velocity Clinical Research High Wycombe ( Site 0406)
High Wycombe HP11 2QW, United Kingdom
Wansford Research ( Site 0429)
Peterborough PE8 6PL, United Kingdom
Royal Cornwall Hospitals NHS Trust ( Site 0410)
Truro TR1 3LJ, United Kingdom
Western General Hospital ( Site 0421)
Edinburgh EH4 2XU, United Kingdom
Queen Elizabeth Hospital, University Hospitals Birmingham NHS Foundation Trust
Birmingham B15 2TH, United Kingdom
Fylde Coast Clinical Research at Layton Medical Centre
Blackpool FY3 7EN, United Kingdom
Southmead Hospital, North Bristol NHS Trust - Clinical Research Centre
Bristol BS10 5NB, United Kingdom
Velocity Clinical Research - Bristol
Bristol BS8 2RA, United Kingdom
Eynsham Medical Centre
Eynsham OX29 4QB, United Kingdom
Velocity Clinical Research - High Wycombe
High Wycombe HP11 2QW, United Kingdom
HMC Health, The Meadows Centre for Health, The Great West Surgery
Hounslow TW4 7NR, United Kingdom
Leeds Teaching Hospitals NHS Trust - St. James's University Hospital
Leeds LS9 7TF, United Kingdom
University Hospitals of Leicester NHS Trust - Leicester Royal Infirmary
Leicester LE1 5WW, United Kingdom
Carolyn Maloney
uhl-tr.researchandinnovationadminmailbox@nhs.net0116 258 8351hVIVO Services Limited
London E1 1EQ, United Kingdom
Panthera Enfield
London EN3 4GS, United Kingdom
Velocity Clinical Research - North London
London N12 8BU, United Kingdom
North Manchester General Hospital
Manchester M8 5RB, United Kingdom
The University of Nottingham Health Service
Nottingham NG7 2QW, United Kingdom
Wansford Research LTD
Peterborough PE8 6PL, United Kingdom
University Hospitals Plymouth NHS Trust
Plymouth PL6 8DH, United Kingdom
Panthera Preston
Preston PR2 9QB, United Kingdom
Panthera Rochdale
Rochdale OL11 4AU, United Kingdom
Velocity Clinical Research - Romford
Romford RM1 3PJ, United Kingdom
Warrington and Halton Teaching Hospitals NHS Foundation Trust
Runcorn WA7 2DA, United Kingdom
Salford Royal Hospital
Salford M6 8HD, United Kingdom
Panthera Sheffield
Sheffield S2 5FX, United Kingdom
University Hospital Southampton NHS Foundation Trust, NIHR Southampton Clinical Research Facility
Southampton SO16 6YD, United Kingdom
Royal Cornwall Hospitals NHS Trust
Truro TR1 3LJ, United Kingdom
Windrush Medical Practice
Witney OX28 6JS, United Kingdom
Panthera York
York YO24 4LJ, United Kingdom
Queen Elizabeth University Hospital ( Site 0422)
Glasgow G51 4TF, United Kingdom
Southampton General Hospital ( Site 0418)
Southampton SO16 0YD, United Kingdom
Velocity Clinical Research Romford ( Site 0427)
London +441708200585, United Kingdom
Layton Medical Centre ( Site 0405)
Blackpool FY3 7EN, United Kingdom
Panthera Biopartners ( Site 0408)
Preston PR2 9QB, United Kingdom
Panthera Biopartners ( Site 0407)
Enfield EN3 4GS, United Kingdom
The Great West Surgery ( Site 0415)
Hounslow TW4 7NJ, United Kingdom
hVIVO ( Site 0404)
London E1 1EQ, United Kingdom
Velocity Clinical Research North London ( Site 0430)
North Finchley N12 8BU, United Kingdom
Panthera Biopartners ( Site 0414)
Rochdale OL11 4AU, United Kingdom
Cripps Health Centre ( Site 0424)
Nottingham NG7 2QW, United Kingdom
Eynsham Medical Centre ( Site 0401)
Eynsham OX29 4QB, United Kingdom
Windrush Medical Centre ( Site 0416)
Witney OX28 6JS, United Kingdom
Aberdeen Royal Infirmary
Aberdeen AB25 2ZD, United Kingdom
NHS Lothian - Western General Hospital
Edinburgh EH4 2XU, United Kingdom
Queen Elizabeth University Hospital, Glasgow Clinical Research Facility
Glasgow G51 4TF, United Kingdom
Cardiff and Vale UHB - University Hospital of Wales
Cardiff CF14 4XW, United Kingdom
University Hospital of Wales ( Site 0420)
Cardiff CF14 4XW, United Kingdom
Queen Elizabeth Hospital ( Site 0411)
Birmingham B15 2TH, United Kingdom
St James's University Hospital ( Site 0425)
Leeds LS9 7TF, United Kingdom
Leicester Royal Infirmary ( Site 0426)
Leicester LE1 5WW, United Kingdom
Carolyn Maloney
uhl-tr.researchandinnovationadminmailbox@nhs.net0116 258 8351North Manchester General Hospital ( Site 0413)
Manchester M8 5RB, United Kingdom
Derriford Hospital ( Site 0417)
Plymouth PL6 8DH, United Kingdom
Salford Royal Hospital ( Site 0419)
Salford M6 8HD, United Kingdom
Panthera Biopartners ( Site 0402)
Sheffield S2 5FX, United Kingdom
Warrington Hospital ( Site 0412)
Warrington WA5 1QG, United Kingdom
Panthera Biopartners ( Site 0403)
York YO24 4LJ, United Kingdom