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PARASTOP - Paracetamol With Strong Opioids

PARASTOP - Paracetamol With Strong Opioids. A Randomized, Double-blind, Parallel-group Non-inferiority Phase III Withdrawal Trial of Paracetamol Versus Placebo in Conjunction With Opioids for Moderate to Severe Cancer-related Pain

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05051735
Acronym
PARASTOP
Enrollment
204
Registered
2021-09-21
Start date
2021-10-20
Completion date
2026-02-18
Last updated
2026-02-25

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

Conditions

Cancer, Cancer Pain

Keywords

Cancer Pain, Pain, Analgesics, Sensory System Agents, Physiological Effects of Drugs

Brief summary

Current guidelines recommend all people with cancer-related pain should be prescribed paracetamol, even those receiving high doses of strong pain killers (opioids) such as morphine. Although this has been shown in studies to be beneficial in other conditions, for instance dental work and after surgery, it has not been shown to further improve pain in people with cancer-related pain. Taking tablets is burdensome to patients and the study aims to determine whether the inconvenience of taking eight extra paracetamol tablets per day can be justified. The study plans to show whether or not pain control is changed (non-inferior) when stopping paracetamol compared to continued use of paracetamol in people already taking strong pain killers for cancer-related pain. Voluntary participants who are taking a combination of paracetamol and a strong opioid are recruited to the study.

Interventions

DRUGParacetamol

Paracetamol 500 mg

DRUGPlacebo

Placebo

Sponsors

Oslo University Hospital
Lead SponsorOTHER
Sykehuset Telemark
CollaboratorOTHER_GOV

Study design

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

Eligibility

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

Inclusion criteria

* Participants must be ≥ 18 years of age inclusive, at the time of signing the informed consent. * ≥50 kg (due to paracetamol dosage) * Participants who are under palliative care or oncology service review * Diagnosis of metastatic cancer * Clinician-predicted life expectancy \>2 months * Receiving daily regular strong opioids for cancer pain * Receiving stable scheduled opioid dose last 48 hours\* * Receiving paracetamol 1 gram x three or four times a day for at least five days * Average pain intensity past 24 hours ≥ 2 and ≤ 7 (NRS 0-10)\* * Able to take study drug/placebo as tablets * Able to comply with all study procedures * Capable of giving signed informed consent as described in Appendix 1 which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol. * It is allowed to repeat procedure within the screening period without considering the participant being a rescreen

Exclusion criteria

* History of allergy or hypersensitivity to any of the active substances or excipients in the study drug * Known severe liver or renal failure equivalent with CTCAE Grade 3 or 4\* precluding continuation of paracetamol. (\*Common Terminology Criteria for Adverse Events (CTCAE) Version 5.0) * Participants receiving subcutaneous, intravenous, intrathecal, or epidural opioid therapy * Participants receiving systemic anticancer treatment during the intervention period if they are anticipated to have increasing pain or other symptoms related to the treatment * Co-enrolment in other drug trials. Participants will not be enrolled in any other on-going interventional clinical trial. Study participants may be enrolled in non-interventional research (e.g. questionnaire, tissue collection studies) * Previously enrolled in this study * Pregnant or lactating women

Design outcomes

Primary

MeasureTime frameDescription
To establish whether placebo with strong opioids compared to paracetamol together with strong opioids provides non-inferior analgesia for cancer-related pain.7 daysNumeric Rating Scale 0-10: Average pain intensity past 24 hours

Secondary

MeasureTime frameDescription
To establish whether placebo with strong opioids compared to paracetamol with strong opioids changes opioid related side effects.7 daysOpioid Side Effects Questionnaire
To establish whether placebo with strong opioids compared to paracetamol with strong opioids changes global rating of improvement.7 daysPatient Global Impression of Change
To establish whether placebo with strong opioids compared to paracetamol with strong opioids changes opioid requirements.7 daysOpioid consumption

Countries

Italy, Norway, Uganda, United Kingdom

Contacts

PRINCIPAL_INVESTIGATORØrnulf Paulsen

Telemark Hospital Trust

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 27, 2026