Effects of the peripherally acting μ-opioid receptor antagonist methylnaltrexone on acute pancreatitis severity: study protocol for a multicentre double-blind randomised placebo-controlled interventional trial, the PAMORA-AP trial

Abstract Background Moderate to severe acute pancreatitis (AP) is associated with a high rate of complications and increased mortality, yet no targeted pharmacologic treatment currently exists. As pain is a dominant symptom in AP, patients are exposed to excess levels of both endo- and exogenous opioids, which may have harmful effects on the course of AP. This trial investigates the effects of the peripherally acting μ-opioid receptor antagonist (PAMORA) methylnaltrexone on disease severity and clinical outcomes in patients with moderate to severe AP. Methods PAMORA-AP is a multicentre, investigator-initiated, double-blind, randomised, placebo-controlled, interventional trial, which will be conducted at four referral centres for acute pancreatitis in Denmark. Ninety patients with early-onset AP (pain onset within 48 h) as well as predicted moderate to severe disease (two or more systemic inflammatory response syndrome criteria upon admission) will be prospectively included. Subsequently, participants will be randomised (1:1) to intravenous treatment with either methylnaltrexone or matching placebo (Ringer’s lactate) during 5 days of admission. The primary endpoint will be the group difference in disease severity as defined and measured by the Pancreatitis Activity Scoring System (PASS) score 48 h after randomisation. Secondary endpoints include daily PASS scores; disease severity according to the Atlanta classification; quantification of need for analgesics, nutritional support, intravenous fluid resuscitation and antibiotics; duration of hospital admissions, readmission rates and mortality. Pain intensity and gut function will be self-reported using validated questionnaires. Exploratory endpoints include circulating levels of pro-and anti-inflammatory markers, polyethylene glycol recovery from the urine, circulating levels of blood markers of intestinal permeability, the prevalence of pancreatic complications on computed tomography (CT) scans, and colon transit time assessed using a CT-based radiopaque marker method. Discussion This trial aims to evaluate the PAMORA methylnaltrexone as a novel targeted pharmacotherapy in patients with moderate to severe AP with the potential benefit of improved patient outcomes. Trial registration ClinicalTrials.govNCT04743570. Registered on 28 January 2021. EudraCT 2020-002313-18.

Download Full-text

Effects of The Peripherally Acting µ-Opioid Receptor Antagonist Methylnaltrexone On Acute Pancreatitis Severity: Study Protocol for a Multicentre Double-Blind Randomised Placebo-Controlled Interventional Trial, The PAMORA-AP Trial

10.21203/rs.3.rs-915419/v1 ◽

2021 ◽

Author(s):

Cecilie Siggaard Knoph ◽

Mathias Ellgaard Cook ◽

Camilla Ann Fjelsted ◽

Srdan Novovic ◽

Michael Bau Mortensen ◽

...

Keyword(s):

Acute Pancreatitis ◽

Receptor Antagonist ◽

Disease Severity ◽

Opioid Receptor ◽

Hospital Admissions ◽

High Rate ◽

Double Blind ◽

Interventional Trial ◽

Opioid Receptor Antagonist ◽

Circulating Levels

Abstract Background: Moderate to severe acute pancreatitis (AP) is associated with a high rate of complications and increased mortality, yet no targeted pharmacologic treatment currently exists. As pain is a dominant symptom in AP, patients are exposed to excess levels of both endo- and exogenous opioids, which may have harmful effects on the course of AP. This trial investigates the effects of the peripherally acting µ-opioid receptor antagonist (PAMORA) methylnaltrexone on disease severity and clinical outcomes in patients with moderate to severe AP. Methods: PAMORA-AP is a multicentre, investigator-initiated, double-blind, randomised, placebo-controlled, interventional trial, which will be conducted at four referral centres for acute pancreatitis in Denmark. Ninety patients with early-onset AP (pain onset within 48 hours) as well as predicted moderate to severe disease (two or more systemic inflammatory response syndrome criteria upon admission) will be prospectively included. Subsequently, participants will be randomised (1:1) to intravenous treatment with either methylnaltrexone or matching placebo (Ringer’s lactate) during 5 days of admission. The primary endpoint will be the group difference in disease severity as defined and measured by the Pancreatitis Activity Scoring System (PASS) score 48 hours after randomisation. Secondary endpoints include daily PASS scores; disease severity according to the Atlanta classification; quantification of need for analgesics, nutritional support, intravenous fluid resuscitation and antibiotics; duration of hospital admissions, readmission rates and mortality. Pain intensity and gut function will be self-reported using validated questionnaires. Exploratory endpoints include circulating levels of pro-and anti-inflammatory markers, polyethylene glycol recovery from the urine, circulating levels of blood markers of intestinal permeability, the prevalence of pancreatic complications on computed tomography (CT) scans, and colon transit time assessed using a CT-based radiopaque marker method. Discussion: This trial aims to evaluate the PAMORA methylnaltrexone as a novel targeted pharmacotherapy in patients with moderate to severe AP with the potential benefit of improved patient outcomes.Trial registration: ClinicalTrials.gov, Identifier: NCT04743570. Registered 28 January 2021, https://clinicaltrials.gov/ct2/show/NCT04743570. EudraCT, Identifier: 2020-002313-18.

Download Full-text

Cardiovascular Safety of the Selective μ-Opioid Receptor Antagonist Naloxegol: A Novel Therapy for Opioid-Induced Constipation

Journal of Cardiovascular Pharmacology and Therapeutics ◽

10.1177/1074248418760239 ◽

2018 ◽

Vol 23 (4) ◽

pp. 309-317 ◽

Cited By ~ 7

Author(s):

William B. White ◽

Peter Kowey ◽

Ulysses Diva ◽

Mark Sostek ◽

Raj Tummala

Keyword(s):

Usual Care ◽

Receptor Antagonist ◽

Opioid Receptor ◽

Development Program ◽

Major Adverse Cardiovascular Events ◽

Rate Pressure Product ◽

Open Label ◽

Double Blind ◽

Opioid Receptor Antagonist ◽

Μ Opioid Receptor

Background: Naloxegol is a novel selective, peripherally acting μ-opioid receptor antagonist for treating opioid-induced constipation (OIC) in patients with chronic pain syndromes. We analyzed the cardiovascular (CV) safety of naloxegol based on data from its development program prior to approval by the US Food and Drug Administration in 2015. Methods: Comprehensive CV safety analyses were performed in 4 clinical studies of naloxegol (12.5 and/or 25 mg) in patients with noncancer pain and OIC: two 12-week, double-blind, randomized studies; a 12-week, double-blind, extension study; and a 52-week, randomized, open-label study versus usual care. Evaluations of baseline CV risk were obtained from medical histories and clinical findings at the time of study initiation. Results: Across the 4 studies (N = 2135), 68% of patients had ≥1 CV risk factor and 41% had a history of CV disease, diabetes, or ≥2 other CV risk factors. There were no increases in blood pressure, heart rate, or the rate-pressure product with naloxegol versus placebo. The rates of major adverse cardiovascular events (MACE) per 100 patient-years of exposure were 1.13 (95% confidence interval [CI], 0.31-2.89) for placebo/usual care and 0.75 (95% CI, 0.24-1.75) for naloxegol. The relative risk of MACE for all doses of naloxegol versus placebo was 0.67 (95% CI, 0.14-3.36). Conclusion: These data demonstrate that naloxegol has a CV safety profile comparable to placebo/usual care in patients with OIC. Although the observed number of events was low, the data show no CV signal in patients with OIC treated with naloxegol.

Download Full-text