Could a new drug combo prevent liver failure after tylenol overdose?
NCT ID NCT05517668
First seen Jun 24, 2026 · Last updated Jun 27, 2026 · Updated 2 times
Summary
This study tested whether adding fomepizole to the standard treatment (N-acetylcysteine) could better protect the liver in people who took too much acetaminophen (Tylenol). The trial included 29 adults and children aged 10 and older who were at high risk for liver injury. The goal was to see if the combination reduced liver damage more than standard care alone.
What this could mean
Our plain-language read of the trial. This is informational only, not medical advice or a prediction.
- Active substance
- Fomepizole (4-MP) given intravenously alongside standard N-acetylcysteine
- What this could lead to
- If it works, this could point toward a better treatment for acetaminophen overdose that reduces liver damage and shortens hospital stays.
- What could go wrong
- This was a small, early-phase trial that was terminated, so results are limited. The added benefit of fomepizole over standard care alone is uncertain and needs more study.
This is an AI summary of the original study and may miss details. Read our disclaimer.
Study facts
What this study's own registry entry says, in plain language.
- Phase
-
Phase 2
Tests whether the treatment actually works, and watches for side effects, in a larger group.
- Participants
-
29 people
The number who actually took part.
- Started
-
Sep 2022
- Finished
-
Nov 2025
- Lead sponsor
-
Other sponsor
The registry's catch-all category, for sponsors it does not file as a company, a government agency, or a research network.
Who can take part
This study's own entry requirements. Only the study team can say for certain whether you qualify.
- Ages
-
10 to 99 years
- Sex
-
Anyone
- Healthy volunteers
-
Not accepted
This study is not open to healthy volunteers. The entry requirements below say who it is open to.
Show the full entry requirements Hide the full entry requirements
Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.
Inclusion Criteria: 1. Evidence of acute or repeated supratherapeutic ingestion (RSTI)\* of acetaminophen (serum acetaminophen greater or equal to 10 mg/L) after correction for bilirubin, when applicable\*\* 2. Baseline AT Multiplication Product at screening (\[APAP\] multiplied by the serum AST or ALT in IU/L, whichever is higher) of 3000 or higher 3. Adults and children ages 10 years or older 4. Infusion of NAC started 8 hours or more post-ingestion 5. Infusion of the study medication begins as early as possible but not later than 24 hours after the initiation of the NAC infusion. 6. Patient presenting to or transferred to the participating site hospital and planned to be admitted to hospital for treatment and/or observation or treatment in Emergency Department 7. Provision of signed and dated informed consent form 8. Stated willingness to comply with mandatory study procedures and availability for the duration of the study Exclusion Criteria: 1. Serum ALT greater than 10,000 IU/L or serum AST greater than 20,000 IU/L at time of screening 2. Another overdose episode with acetaminophen within the preceding 14 days 3. Baseline ALT (defined as average of ALTs reported in preceding 12 months) above the ALT reference range for the hospital laboratory unless screening ALT is at least twice the patient's baseline value. 4. Evidence of chronic decompensated liver cirrhosis regardless of serum ALT activity\*\*\* 5. Known allergic reaction to acetylcysteine or a documented serious hypersensitivity reaction to fomepizole or other pyrazoles. 6. Pregnancy or lactation 7. Co-ingestion of other known activators or inhibitors of CYP2E1 (acetone, cimetidine, nicotine, isoniazid, pyridine, pyrazole, disulfiram). History of cigarette smoking, use of nicotine patches are allowed. 8. Concomitant ingestion of high dosage iron preparations (e.g., prenatal iron sulfate capsules) 9. In the site investigator's judgment, the patient has a condition that would interfere with evaluation of the efficacy of fomepizole. These conditions include, but are not limited to the following conditions: * Seizure in the previous 24 hours. History of seizure disorder under chronic treatment is allowed * Cardiac arrest in the preceding 14 days * Cardiac dysrhythmia that compromises cardiovascular function at screening * History of liver transplant * Shock liver 10. Treatment with another investigational drug within the preceding 30 days. 11. Previous participation in this study * Acute ingestion is defined as more than 4 grams ingested over 24-hour period. RSTI defined as more than 4 grams ingested/24 hour period for more than 24 hours. Note: the type of ingestion (acute vs. RSTI) or its timing relative to time of hospital admission do not affect neither study eligibility nor research subject management. * Bilirubinemia (high bilirubin in blood) may cause falsely elevated APAP levels when tested with spectrophotometric assay (SPA). In order to rule out this false elevation we recommend validating APAP level via liquid chromatography (LC) or mass spectrometry (MS) testing methods after we enroll a patient with APAP test results between 10 and 30 mg/L and total bilirubin ≥ 10 mg/dL. * Decompensated cirrhosis refers to a stage of liver cirrhosis where the liver is no longer able to function properly due to extensive damage, scarring, and fibrosis. Patients with decompensated cirrhosis may have symptoms such as jaundice (yellowing of the skin and eyes), ascites (abdominal swelling), gastrointestinal bleeding, spider angiomas (red, spider-like lesions on the skin), hepatic encephalopathy (confusion and cognitive impairment), or hepatorenal syndrome (kidney dysfunction). Decompensated cirrhosis is a more advanced and serious stage of liver disease, and patients may require hospitalization and more aggressive medical interventions, including liver transplantation.
Get updates
Get notified about this study
Sign up to get updates when this study changes or when new studies for Acetaminophen are added.
Genom att skicka in godkänner du våra Användarvillkor
Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Locations
-
Denver Health and Hospital Authority
Denver, Colorado, 80204, United States
More trials for these conditions
Other studies related to the condition(s) this trial covers.
- A new way to read CT scans may predict which liver surgery patients will develop Life-Threatening failure
- Can a simple guide help clinicians better address youth substance use?
- A machine that keeps donor livers alive outside the body — could it transform transplantation?
- AI may solve tricky liver diagnosis puzzle
- Smartphone tools aim to cut overdose risk for drug users
- Could a radiation and antibody combo free liver transplant patients from daily pills?