About This Tool

The Remicade Dosing Calculator is an educational resource designed to assist healthcare professionals in calculating infliximab dosage based on patient weight, clinical indication, and treatment phase. It simplifies the process of determining the total dose, number of vials needed, and administration schedule for both induction and maintenance therapy.

Understanding the Outputs

Upon entering the required information, the calculator provides a detailed summary for the specified dose:

• Calculated Total Dose: The precise dose in milligrams (mg) based on the patient’s weight and the selected mg/kg regimen.
• Number of 100 mg Vials: The total number of vials required, rounded up to the nearest whole vial to ensure the full calculated dose can be administered.
• Total Drug Dispensed: The total amount of infliximab in milligrams available from the required number of vials (e.g., 3 vials = 300 mg).
• Wasted Drug: The amount of reconstituted drug in milligrams that will be discarded after the calculated dose is drawn. This occurs because doses are rounded up to the nearest 100 mg vial.
• Final Volume to Administer: The volume in milliliters (mL) to be infused, assuming a standard reconstitution concentration of 10 mg/mL.
• Dosing Schedule: A clear outline of the administration timing, showing the weeks for induction doses (0, 2, and 6) or the frequency for maintenance therapy (e.g., every 8 weeks).

How to Use the Calculator

1. Enter Patient Weight: Input the patient’s weight and select the appropriate unit (kg or lbs).
2. Select Indication: Choose the relevant clinical indication from the dropdown menu (e.g., Crohn’s Disease, Rheumatoid Arthritis).
3. Choose Dosing Regimen: Select the desired dose in mg/kg. The available options will update automatically based on the chosen indication.
4. Select Dosing Phase: Specify whether the calculation is for the initial induction phase or ongoing maintenance therapy.
5. Review Results: The calculated dose, vial requirements, and administration schedule will be displayed instantly.

Dosing Overview

Remicade (infliximab) dosing is weight-based and varies by indication. The standard induction schedule for most approved conditions is infusions at weeks 0, 2, and 6.

• Crohn’s Disease & Ulcerative Colitis: Typically 5 mg/kg, with an option to escalate to 10 mg/kg in Crohn’s Disease if response is inadequate. Maintenance is every 8 weeks.
• Rheumatoid Arthritis: Starts at 3 mg/kg, with options to increase to 10 mg/kg. Maintenance is every 8 weeks, but frequency can be increased to every 4 weeks.
• Ankylosing Spondylitis, Psoriatic Arthritis, & Plaque Psoriasis: Standard dose is 5 mg/kg. Maintenance for Ankylosing Spondylitis is every 6 weeks, while it is every 8 weeks for Psoriatic Arthritis and Plaque Psoriasis.

Switching Biologics

Switching a patient from another biologic agent to infliximab requires careful clinical consideration. The decision should be based on the reason for the switch (e.g., primary non-response, secondary loss of response, adverse event), the previous therapy, and the patient’s clinical status. There is no single universal protocol, and the timing of the first infliximab infusion should be determined by the treating clinician. Generally, the induction dose schedule is initiated as if the patient were treatment-naïve.

Missed Dose Protocol

If a patient misses a scheduled infliximab infusion, the next dose should be administered as soon as possible. The subsequent maintenance schedule should then be re-established based on the date of this most recent infusion. The treating physician should be consulted to determine the best course of action for the individual patient.

Safety Information

This tool is for educational purposes and does not replace clinical judgment or official prescribing information. Infliximab has important safety considerations that clinicians must be aware of before and during treatment.

Frequently Asked Questions

How does the calculator handle weight in pounds (lbs) versus kilograms (kg)?
The calculator automatically converts the weight entered in pounds to kilograms using the standard conversion factor (1 kg ≈ 2.20462 lbs) before calculating the dose. The final results are based on the kilogram weight.

What is the difference between the “Induction Phase” and “Maintenance Phase”?
The induction phase is the initial series of doses given to establish a therapeutic level of the medication in the body, typically at weeks 0, 2, and 6. The maintenance phase consists of ongoing, regularly scheduled doses (e.g., every 8 weeks) to maintain that therapeutic level.

Why does the calculator show different dose options for Rheumatoid Arthritis?
The prescribing information for Rheumatoid Arthritis allows for a starting dose of 3 mg/kg, which can be increased in increments up to 10 mg/kg for patients with an inadequate response. The calculator provides these common options to reflect clinical practice.

How is the number of 100 mg vials determined?
The calculator divides the total calculated dose (in mg) by 100. Since only whole vials can be used, the result is always rounded up to the next whole number to ensure the patient receives the full prescribed dose.

What does “wasted drug” mean?
This is the amount of reconstituted medication left over after the exact calculated dose is drawn from the vials. For example, if a patient needs 240 mg, three 100 mg vials (300 mg total) are required. The remaining 60 mg is the “wasted drug.”

What is the maintenance schedule for Ankylosing Spondylitis according to the tool?
The tool reflects the approved dosing schedule, which is an infusion every 6 weeks for the maintenance phase of Ankylosing Spondylitis.

Can this calculator be used for infliximab biosimilars?
While dosing for biosimilars is generally the same as for the reference product (Remicade), you should always consult the specific prescribing information for the biosimilar being used.

Is this tool a substitute for official prescribing information?
No. This calculator is an educational and informational aid only. It is not a substitute for clinical judgment. All calculations should be verified against the official, most current prescribing information for Remicade (infliximab).

References

1. REMICADE® (infliximab) Prescribing Information. U.S. Food and Drug Administration. Horsham, PA: Janssen Biotech, Inc.
2. Remicade (infliximab) European public assessment report (EPAR). European Medicines Agency.
3. Remicade® (infliximab) for Healthcare Professionals. Janssen CarePath.
4. Lichtenstein GR, Loftus EV, Isaacs KL, Regueiro MD, Gerson LB, Sands BE. ACG Clinical Guideline: Management of Crohn’s Disease in Adults. Am J Gastroenterol. 2018;113(4):481-517.