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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
PIANO: Pharmacokinetics of Ibuprofen and Acetaminophen in Normal and Overweight adults
Scientific title
PIANO: Pharmacokinetics of Ibuprofen and Acetaminophen in Normal and Overweight adults
A single-dose, open-label, feasibility study to assess the impact of varying body mass index (BMI) on the pharmacokinetics of acetaminophen (paracetamol) and ibuprofen in adults.
Secondary ID [1] 1567 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Pharmacokinetics of analgesics in obesity 256977 0
Condition category
Condition code
Anaesthesiology 257128 257128 0 0
Pain management

Study type
Description of intervention(s) / exposure
Each subject will recevie a single oral dose of 1g paracetamol and 400mg ibuprofen on a single occasion. Treatment will be administered with 500mL of water under fasting conditions.
Intervention code [1] 256153 0
Treatment: Drugs
Comparator / control treatment
No comparator/control treatment will be administered. All subjects will be administered paracetamol & ibuprofen; pharmacokinetics will be assessed across body weight groups.
Control group

Primary outcome [1] 258021 0
To investigate the impact of varying body mass index on paracetamol, ibuprofen and metabolite pharmacokinetics in adults.
Timepoint [1] 258021 0
Screening: within 1 month prior to treatment administration.
Study Visit: Subjects are confined to the study unit from prior to dosing until 8 hours after treatment administration. Fingerprick blood and saliva samples for pharmacokinetic analysis will be collected prior to dosing, 0.5, 1, 1.5, 2, 3, 4, 6 & 8 hours after treatment administration.
Secondary outcome [1] 263583 0
To determine the relationship between venous blood plasma paracetamol, ibuprofen and metabolite concentrations and those obtained from saliva and fingerprick blood samples.
Timepoint [1] 263583 0
Venous blood, saliva and fingerprick blood samples will be collected at 0.5, 2 & 4 hours after treatment administration.

Key inclusion criteria
1. Participant is >18 years of age at the time of informed consent.
2. Participant in a male or non-pregnant (as evidenced by a negative urine pregnancy test in women of child-bearing potential), non-lactating female.
3. Particpant is a non-smoker.
4. Participant has previously received 2 or more doses each of paracetamol and ibuprofen with no significant adverse events.
5. Participant is aware of the study procedures and the risks involved, and voluntarily agrees to participate by providing written informed consent.
Participants shall be classified as normal weight (18.5-25mg/m2), overweight (25-30kg/m2) or obese (>30kg/m2) based on BMI.
Minimum age
18 Years
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
1. Participant has a history of allergy and/or sensitivity to paracetamol or non-steroidal anti-inflammatory drugs.
2. Participant has a medical condition or has received treatment with a pharmacologic agent for which administration of paracetamol and/or ibuprofen is contraindicated as outlined in the current product information.
3. Participant has a history or current evidence of any condition, therapy or laboratory abnormality that, in the opinion of the medical officer, might affect the results of the study or may not be in the best interest of the participant to take part.
4. Participant has received treatment with paracetamol or ibuprofen containing products within 24 hours of study treatment administration.

Study design
Purpose of the study
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
All subjects will be allocated to recevie the same study treatment (single oral dose of 1g paracetamol and 400mg ibuprofen). Equal numbers of participants will be recruited into each BMI classification group (ie. normal weight 18.5-25kg/m2; overweight 25-30kg/m2; obese >30kg/m2).
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Not randomised.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Single group
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment postcode(s) [1] 2627 0

Funding & Sponsors
Funding source category [1] 256661 0
Name [1] 256661 0
University of South Australia
Address [1] 256661 0
GPO Box 2471
Adelaide, SA, 5001
Country [1] 256661 0
Primary sponsor type
University of South Australia
GPO Box 2471
Adelaide, SA, 5001
Secondary sponsor category [1] 256033 0
Name [1] 256033 0
Not applicable
Address [1] 256033 0
Not applicable
Country [1] 256033 0

Ethics approval
Ethics application status
Ethics committee name [1] 258683 0
University of South Australia Human Research Ethics Committee
Ethics committee address [1] 258683 0
GPO Box 2471
Adelaide, SA, 5001
Ethics committee country [1] 258683 0
Date submitted for ethics approval [1] 258683 0
Approval date [1] 258683 0
Ethics approval number [1] 258683 0

Brief summary
Whilst paracetamol and ibuprofen are relatively safe and effective medications, high doses have been associated with potentially fatal liver damage or gastrointestinal problems whilst administration of low doses can result in inadequate treatment of pain and/or fever. This study is being conducted to investigate how increased body size impacts on how the body handles these medications. It is proposed that the results of this study will be used to guide dosing strategies for patients who are overweight or obese.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 30946 0
Address 30946 0
Country 30946 0
Phone 30946 0
Fax 30946 0
Email 30946 0
Contact person for public queries
Name 14193 0
Stephanie Reuter
Address 14193 0
University of South Australia
GPO Box 2471
Adelaide, SA, 5001
Country 14193 0
Phone 14193 0
Fax 14193 0
Email 14193 0
Contact person for scientific queries
Name 5121 0
Stephanie Reuter
Address 5121 0
University of South Australia
GPO Box 2471
Adelaide, SA, 5001
Country 5121 0
Phone 5121 0
Fax 5121 0
Email 5121 0

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary