About This Calculator

The Lemtrada (alemtuzumab) Dosing Calculator is a clinical support tool for healthcare professionals. It helps generate an administration schedule for the two initial treatment courses based on the standard dosing regimen outlined in the prescribing information. This tool is not a substitute for clinical judgment and all outputs must be verified.

Outputs

After entering the required information, the calculator will generate a detailed regimen summary, which includes:

• Treatment Schedule: A table displaying the exact dates for each infusion day for the selected course (5 days for Course 1; 3 days for Course 2).
• Dose Per Infusion: Confirmation of the standard 12 mg dose for each administration.
• Infusion Preparation: A summary of daily preparation steps, including the volume to withdraw (1.2 mL), recommended diluents (0.9% NaCl or D5W), and total infusion volume (101.2 mL).
• Administration Notes: Key parameters such as the required infusion duration (4 hours).

How to Use

To generate a dosing schedule, follow these steps:

1. Patient Identifier (Optional): Enter patient initials or an ID for documentation purposes. This information is not stored.
2. Select Treatment Course: Choose between “Course 1” and “Course 2”.
3. Select Start Date: Enter the start date of the original Course 1. If calculating for Course 2, the tool will automatically project the start date to 12 months after the date you enter.
4. Review Results: The complete dosing schedule and preparation details will appear instantly.

Dosing Overview

Lemtrada is administered as two treatment courses. It is crucial to adhere to the specified interval between courses and to complete all required premedication and monitoring.

• Course 1: 12 mg/day administered by intravenous infusion for 5 consecutive days (total dose of 60 mg).
• Course 2: 12 mg/day administered by intravenous infusion for 3 consecutive days (total dose of 36 mg), given 12 months after the first course.
• Premedication: Corticosteroids (e.g., 1,000 mg methylprednisolone) must be administered for the first 3 days of each course.
• Prophylaxis: Anti-herpetic prophylaxis (e.g., acyclovir) should be started on day 1 of each course and continued for at least 2 months after completion, or until the CD4+ count is ≥200 cells/μL.

Switching

When switching a patient to Lemtrada from another disease-modifying therapy (DMT), healthcare providers must consult the full prescribing information. Considerations include the half-life and mechanism of action of the prior therapy to minimize the risk of overlapping immunosuppressive effects or additive risk of adverse events. A suitable washout period may be necessary.

Missed Dose

This calculator does not provide guidance for missed doses. Per the prescribing information, if a dose of Lemtrada is missed, it should not be given on the same day as a scheduled dose. The treatment course may be extended beyond the 5 or 3 consecutive days. Any deviation from the planned schedule should be based on clinical judgment.

Safety Alerts

Due to its safety profile, patients must be monitored for 48 months after their last infusion. Key monitoring includes:

• Complete Blood Count (CBC) with differential: Monthly.
• Serum Creatinine levels: Monthly.
• Urinalysis with urine cell counts: Monthly.
• Thyroid Stimulating Hormone (TSH): Every 3 months.
• Annual Skin Exam: To assess for melanoma.

FAQ

What happens if I select “Course 2” in the calculator?
The tool will calculate a 3-day infusion schedule with a start date that is exactly 12 months after the “Course 1 Start Date” you enter.

Does the calculator adjust the dose for patient weight?
No. The calculator uses the standard fixed dose of 12 mg per infusion, which is not weight-based.

What is the total cumulative dose calculated for each course?
The calculator schedules a total dose of 60 mg for Course 1 (12 mg x 5 days) and 36 mg for Course 2 (12 mg x 3 days).

Can I use this tool for treatment courses beyond the second?
No, this tool is designed only for the initial two treatment courses as specified in the FDA-approved label. The safety and efficacy of more than two courses have not been established.

What diluents are used for the infusion?
As shown in the calculator’s output, Lemtrada should be diluted in 100 mL of either 0.9% Sodium Chloride Injection (Normal Saline) or 5% Dextrose in Water (D5W).

Why is the monitoring period required for 48 months?
The extended monitoring period is necessary to detect delayed-onset autoimmune disorders, including immune thrombocytopenia (ITP), nephropathies, and thyroid disorders, which can occur months to years after the last dose.

Does this calculator store any patient data?
No. The tool operates entirely within your browser. No patient information or calculation data is saved or transmitted.

Is there a difference in the daily dose between Course 1 and Course 2?
No, the daily dose is 12 mg for both courses. The only difference is the duration: 5 consecutive days for Course 1 and 3 consecutive days for Course 2.

References

• LEMTRADA® (alemtuzumab) Prescribing Information. U.S. Food and Drug Administration.
• Lemtrada (alemtuzumab) European Public Assessment Report (EPAR). European Medicines Agency.
• Lemtrada Official Healthcare Professional Website. Sanofi.
• Alemtuzumab for treating relapsing-remitting multiple sclerosis. National Institute for Health and Care Excellence (NICE).