Monitoring Liver Enzymes in Patients Taking Bimzelx (Bimekizumab)
Test liver enzymes (ALT, AST), alkaline phosphatase, and bilirubin at baseline, then periodically during treatment with BIMZELX according to routine patient management. 1
Baseline Testing Requirements
Before initiating BIMZELX, obtain:
These baseline values are essential because treatment with BIMZELX was associated with increased incidence of liver enzyme elevations compared to placebo in randomized clinical trials 1.
Periodic Monitoring During Treatment
The FDA label does not specify exact monitoring intervals but recommends "periodically during treatment" and "according to routine patient management." 1 However, based on general biologic monitoring principles for similar agents, reasonable approaches include:
- Every 3-6 months for stable patients without risk factors 2
- More frequently if baseline liver enzymes are elevated or if the patient has risk factors for hepatotoxicity 2
The key liver tests to monitor include ALT, AST, ALP, and total bilirubin 2.
Clinical Context from Trial Data
In phase 3/3b trials over 2 years with 2,186 patients:
- The exposure-adjusted incidence rate (EAIR) of hepatic adverse events was 3.5 per 100 patient-years 3
- ALT/AST elevations >3× upper limit of normal (ULN) occurred at a rate of 2.3 per 100 patient-years 3
- ALT/AST elevations >5× ULN occurred at a rate of 0.6 per 100 patient-years 3
- Rates were similar to comparators (adalimumab, secukinumab, ustekinumab) during controlled periods 3
- Hepatic adverse event rates remained consistent through 2 years without increasing from first to second year 3
Management of Elevated Liver Enzymes
For Mild Elevations (≤3× ULN):
- Continue BIMZELX with increased monitoring frequency 2
- Recheck liver enzymes at shorter intervals (e.g., every 1-2 weeks) 4
- Review all medications and supplements for potential hepatotoxicity 2, 4
For Moderate Elevations (>3× ULN):
- Interrupt BIMZELX if drug-induced liver injury is suspected 1
- Increase monitoring frequency to every 3-7 days 4
- Investigate alternative causes: viral hepatitis, alcohol use, medications, imaging for liver metastases or structural abnormalities 2, 5
- Consider additional testing: GGT, direct bilirubin, viral hepatitis panel, autoimmune markers 2, 5
For Severe Elevations (>5× ULN) or Combined Elevations:
- Permanently discontinue BIMZELX if causally associated combined elevations of transaminases and bilirubin occur 1
- This meets Hy's Law criteria (ALT >3× ULN with total bilirubin >2× ULN), which predicts serious drug-induced liver injury 5
- Consider hepatology consultation 2
Special Populations to Avoid
Avoid use of BIMZELX in patients with:
These patients may be at increased risk for severe hepatic injury 1.
Pattern Recognition
When evaluating elevated liver enzymes in BIMZELX-treated patients, determine if the pattern is:
- Hepatocellular (predominant ALT/AST elevation) 2, 5
- Cholestatic (predominant ALP elevation) 2, 5
- Mixed pattern 5
Drug-induced liver injury from BIMZELX typically presents as hepatocellular injury with aminotransferase elevations 1. Elevated liver serum transaminases have resolved after discontinuation of BIMZELX in clinical trials 1.
Common Pitfalls to Avoid
- Don't ignore mild elevations - 84% of mild liver enzyme elevations remain abnormal on retesting after 1 month 5
- Don't continue BIMZELX with combined transaminase and bilirubin elevations - this requires permanent discontinuation 1
- Don't overlook alternative causes - disease progression, other medications, alcohol, viral hepatitis, and metabolic conditions are common causes of liver enzyme elevation 6, 5
- Don't fail to document baseline values - this is essential for interpreting subsequent elevations 1
Additional Monitoring Considerations
Obesity, diabetes, dyslipidemia, and chronic alcohol consumption are confounding factors for hepatic dysfunction in psoriasis patients 3. These comorbidities are common in the psoriasis population and should be considered when interpreting liver enzyme elevations 3.