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Efficacy and Safety of Methoxyflurane (Penthrox) for the Treatment of Acute Pain in Minor Trauma

A Randomised, Double Blind, Multi-centre, Placebo Controlled Study to Evaluate the Efficacy and Safety of Methoxyflurane (Penthrox) for the Treatment of Acute Pain in Patients Presenting to an Emergency Department With Minor Trauma

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01420159
Acronym
STOP!
Enrollment
300
Registered
2011-08-19
Start date
2011-08-31
Completion date
2012-07-31
Last updated
2012-10-31

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Acute Pain Due to Trauma

Keywords

Pain, Trauma, Analgesia

Brief summary

This study investigates the treatment of acute pain, an unpleasant feeling caused by an injury. The overall purpose of the study is to gain more information that the pain relief medicine Penthrox(Methoxyflurane) administered using the Penthrox Inhaler(a distinctive green, whistle like object that you breathe through) is safe and works at relieving pain in patients aged 12 years and older who are admitted to a hospital Emergency Department with a minor injury (known as trauma).

Interventions

Patients will have access to two 3 mL methoxyflurane (Penthrox) Inhalers or two 5mL placebo Inhalers to be self-administered.

Sponsors

ORION Clinical Services
CollaboratorINDUSTRY
Medical Developments International Limited
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
12 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Patients 12 years of age or older who are able to give written informed consent or who are accompanied by a parent(s)/legal guardian able to provide written informed consent on their behalf. * Evidence of signed and dated informed consent document(s) indicating that the patient (and/or a parent/legal guardian) has been informed of all pertinent aspects of the study. * Pain Score ≥ 4 to ≤ 7 as measured using Numerical Rating Scale (NRS) at the time of admission, due to minor trauma.

Exclusion criteria

* Life-threatening condition requiring immediate admission in the Operating Room or Intensive Care Unit. * Presence of any other clinical condition(s) that may, in the opinion of the investigator, impact on the patient's ability to participate in the study, or on the study results, including history of head injury and/or altered consciousness. * Unable to provide written informed consent. * Known pregnancy or lactation * Acute intoxication with drugs or alcohol, based on the judgement of the attending physician. * Treatment with any analgesic agent within 5 hours prior to presentation to ED (except diclofenac sodium which is prohibited within 8 hours prior to presentation to ED). * Current ongoing use of analgesics for chronic pain. * Use of an investigational product within one month prior to presentation to ED. * Known personal or familial hypersensitivity to fluorinated anaesthetics. * Known personal or familial history of malignant hyperthermia. * Clinically significant respiratory depression. * Use of methoxyflurane in the previous 4 weeks. * Known pre-existing clinically significant renal or hepatic impairment according to the judgement of the clinician. * Clinically significant cardiovascular instability.

Design outcomes

Primary

MeasureTime frameDescription
VAS ScoreTwenty MinutesThe difference between treatment and placebo on the VAS pain score

Secondary

MeasureTime frameDescription
Rescue MedicationUp to a maximum of 6 hoursA request for rescue medication, time of request for rescue medication and the quantity of opioid equivalent rescue medication administered will be measured
Time to pain reliefUp to a maximum of 6 hoursThe number of inhalations of study treatment until pain relief is achieved and the time until pain relief is achieved.
Responder analysisUp to a maximum of 6 hoursThe number of responders will be defined
Safety AnalysisUp to 16 daysEvaluation of Adverse Events experienced during treatment. Evaluation of Adverse Events, including safety laboratory samples, up to 14 +/- 2 days following Emergency Department discharge

Countries

United Kingdom

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Mar 12, 2026