An unblinded randomized study of influenza A/H1N1 2009 (swine flu) resistance under standard and double dose oseltamivir treatment in participants with influenza

• Register: ANZCTR
• Last refreshed on: 22 February 2013
• Main ID: ACTRN12610000004066
• Date of registration: 05/01/2010
• Primary sponsor: University National Centre for Immunisation Research and Surveillance (NCIRS)
• Public title: An unblinded randomized study of influenza A/H1N1 2009 (swine flu) resistance under standard and double dose oseltamivir treatment in participants with influenza
• Scientific title: An unblinded randomized study of influenza A/H1N1 2009 resistance under standard and double dose oseltamivir treatment in participants with influenza
• Date of first enrolment: 1/12/2009
• Target sample size: 125
• Recruitment status: Recruiting
• URL: http://www.anzctr.org.au/ACTRN12610000004066.aspx
• Study type: Interventional
• Study design: Randomised controlled trial Parallel

Countries of recruitment

Australia

Contacts

• Name: Prof Robert Booy

• Name: Prof Robert Booy

Key inclusion & exclusion criteria

Inclusion criteria: Participants must meet all of the following inclusion criteria to participate in this study:
1. The age of the patient is at least 5 years.
2. The patient has a positive rapid antigen test for influenza A and symptoms indicative of influenza that have lasted
no more than 48 hours:
- fever >= 37.8 celsius and
- at least one respiratory symptom (cough, coryza, sore throat, rhinitis)
Exclusion criteria: If one or more of the following criteria are met, the participant will be ineligible to take part in this study:
1. Clinical suspicion of infection with a respiratory virus other than influenza.
2. Suspicion of invasive bacterial infection requiring immediate admission to hospital.
3. Evidence of a poorly controlled underlying medical condition.
4. Known immunosuppression (malignancy, transplant, drugs)
5. Pregnant or lactating females
6. Known allergy to oseltamivir.
7. Participation in another clinical trial with an investigational drug.
8. Participant with insufficient English language skills.
9. A person about whom the investigator thinks that the person is unlikely to comply with the study requirements.

Age minimum: 5 Years
Age maximum: 0 No limit
Gender: Both males and females

Health Condition(s) or Problem(s) studied

Influenza

Intervention(s)

The main purpose of this study is to assess the frequency of emergence of oseltamivir resistant viruses, and their virological characteristics, in patients treated with standard and double dose oseltamivir (oral capsules or suspension) for influenza caused by A/H1N1 2009 (‘swine flu’) and other human influenza viruses during periods of high transmission. Limited clinical information will also be collected.

This is an unblinded randomized study. Patients with clinical symptoms indicative of influenza, who present within 48 hours of the onset of fever during confirmed influenza activity in the community, will be randomized to receive immediate treatment with oseltamivir at a standard age-appropriate dose or a double dose, twice daily for 5 days. Patients will have baseline virus samples taken for typing and oseltamivir sensitivity and also on day 5 of treatment.

Primary Outcome(s)

The objectives of this study are to investigate the effectiveness of double dose Oseltamivir treatment initiated within 48 hours of the onset of influenza symptoms compared with standard dose Oseltamivir on:
Primary
1. frequency of isolation of resistant virus in subject aged 5 years or greater.

Virological test including culture/polymerase chain reaction (PCR) will be done to check viral resistance.

Secondary Outcome(s)

1. reductions in viral load

2. Presence or absence of clinical signs and symptoms in patients shedding resistant virus at day 5.

3. Do those who begin treatment after 24 hours and up to 48 hours derive benefit from the treatment? Stratified analysis by duration (<24hours, 24 to 48hours) of symptoms before commencement of treatment.

Secondary ID(s)

None

Source(s) of Monetary Support

Roche Products Pty Ltd