Briefly noted: Induction Infliximab Levels

K Clarkston et al. JPGN 2019; 69: 68-74. This pediatric study with 72 children/young adults with Crohn’s disease examined infliximab trough levels; 70 received infliximab monotherapy & 88% received “standard” dose of 5 mg/kg

Key findings:

  • Infliximab level ≥18 mcg/mL at week 6 was strongly associated with clinical and biologic response as well as achieving an infliximab level ≥5 mcg/mL at week 14 (AUC 0.85).
  • A week 6 level ≥18 mcg/mL had 82% sensitivity, 82% specificity, 56% PPC, and 94% NPV  for having a therapeutic level at 4th infusion.
  • Median infliximab levels for clinical responders was 27.8 mcg/mL at 2nd infusion and 14 mcg/mL at 3rd infusion.
  • The authors reported that only 22% of their cohort achieved a week 14 infliximab level ≥5 mcg/mL. The median infliximab level at this time point was 2.1 mcg/mL.

My take: In this study, the standard dose of infliximab (5 mg/kg) was not adequate in ~80% of patients in achieving a therapeutic trough level.  If using the standard low-dose, it may be worthwhile to check a trough level prior to 3rd infusion or at week 10 to help determine if the level will be sufficient to start maintenance treatment at week 14 or whether an earlier infusion is warranted.

Related blog posts:

Barcelona

Disclaimer: These blog posts are for educational purposes only. Specific dosing of medications/diets (along with potential adverse effects) should be confirmed by prescribing physician/nutritionist.  This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.

 

2 thoughts on “Briefly noted: Induction Infliximab Levels

  1. Pingback: Non-Adherence Leads to Treatment Escalation and More on Early Infliximab Trough Levels | gutsandgrowth

  2. Pingback: Proactive Therapeutic Drug Monitoring -Different Time Points | gutsandgrowth

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.