About This Guide
This guide provides detailed context for the Stelara Dosing Calculator. It explains the tool's inputs, outputs, and the clinical dosing principles it uses, based on the official prescribing information for ustekinumab. This information is intended for educational purposes and should not replace clinical judgment or official drug labeling.
Calculator Outputs Explained
After you input the required patient data, the calculator will provide the following key information:
- Calculated Dose: The specific dose in milligrams (mg) recommended for the patient based on their weight, indication, and treatment phase.
- Administration Route: The method of delivery, which will be either Intravenous (IV) Infusion for induction in CD/UC or Subcutaneous (SQ) Injection for all other scenarios.
- Dosing Schedule: The recommended frequency of administration, such as a one-time induction dose, or a recurring schedule (e.g., every 8 or 12 weeks).
How to Use the Calculator
Follow these simple steps to determine the correct Stelara dose:
- Select Indication: Choose the relevant condition from the dropdown menu (Crohn's Disease, Ulcerative Colitis, Plaque Psoriasis, or Psoriatic Arthritis).
- Enter Patient Weight: Input the patient's weight and select the correct unit (kg or lbs). The tool will automatically convert lbs to kg for calculations.
- Specify Patient Group: Depending on the indication, select the dosing phase (Induction/Maintenance for CD/UC) or patient type (Adult/Pediatric for PsO/PsA).
- Calculate: Click the "Calculate" button to view the recommended dosing regimen.
Stelara Dosing Overview
The calculator's logic is based on the following FDA-approved dosing regimens.
Crohn's Disease (CD) & Ulcerative Colitis (UC) - Adults
Treatment begins with a weight-based intravenous induction dose, followed by fixed subcutaneous maintenance doses.
| Phase | Patient Weight | Dose | Route | Schedule |
|---|---|---|---|---|
| Induction | ≤ 55 kg | 260 mg | IV Infusion | Single dose at Week 0 |
| Induction | > 55 kg to ≤ 85 kg | 390 mg | IV Infusion | Single dose at Week 0 |
| Induction | > 85 kg | 520 mg | IV Infusion | Single dose at Week 0 |
| Maintenance | All weights | 90 mg | SQ Injection | Every 8 weeks, starting at Week 8 |
Plaque Psoriasis (PsO) & Psoriatic Arthritis (PsA) - Adults
Dosing is administered subcutaneously and is based on patient weight.
| Patient Weight | Dose | Route | Schedule |
|---|---|---|---|
| ≤ 100 kg | 45 mg | SQ Injection | Week 0, Week 4, then every 12 weeks |
| > 100 kg | 90 mg | SQ Injection | Week 0, Week 4, then every 12 weeks |
Plaque Psoriasis (PsO) - Pediatric (6-17 years)
Pediatric dosing for Plaque Psoriasis is also weight-based and administered subcutaneously.
| Patient Weight | Dose | Route | Schedule |
|---|---|---|---|
| < 60 kg | 0.75 mg/kg | SQ Injection | Week 0, Week 4, then every 12 weeks |
| ≥ 60 kg to ≤ 100 kg | 45 mg | SQ Injection | Week 0, Week 4, then every 12 weeks |
| > 100 kg | 90 mg | SQ Injection | Week 0, Week 4, then every 12 weeks |
Switching Medications
Decisions about switching to or from Stelara require careful clinical evaluation. This includes considering the patient's treatment history, disease activity, and the pharmacokinetic properties of the involved medications. There is no standard washout period, and the process should be individualized under the guidance of a specialist.
Managing a Missed Dose
If a patient misses a scheduled subcutaneous dose of Stelara, they should be advised to administer it as soon as they remember. The subsequent dose should then be rescheduled based on this new administration date to maintain the correct interval. Patients should be instructed to contact their healthcare provider for specific guidance.
Safety Alerts & Considerations
Before initiating Stelara, healthcare providers must consider the following:
- Infections: Stelara may lower the ability to fight infections. Evaluate patients for tuberculosis (TB) prior to starting treatment and monitor for signs of infection during and after treatment.
- Malignancies: Immunosuppressants like ustekinumab may increase the risk of malignancy.
- Hypersensitivity Reactions: Serious hypersensitivity reactions, including anaphylaxis, have been reported. If such a reaction occurs, discontinue Stelara immediately.
- Live Vaccinations: Avoid use of live vaccines in patients treated with Stelara.
Frequently Asked Questions (FAQ)
Why is weight required for the IV induction dose but not for SQ maintenance?
The initial IV induction dose for Crohn's Disease and Ulcerative Colitis is calculated based on weight to achieve therapeutic drug levels quickly (approx. 6 mg/kg). The subsequent SQ maintenance dose is a fixed 90 mg dose proven effective for maintaining those levels, regardless of weight.
What dose does the calculator show for a 75 kg adult with Plaque Psoriasis?
For a 75 kg patient (which is ≤ 100 kg), the calculator will recommend a 45 mg subcutaneous dose administered at Week 0, Week 4, and every 12 weeks thereafter.
Can I use this tool for a 5-year-old patient?
No. The calculator's pediatric logic is for patients aged 6-17 years with Plaque Psoriasis, as per the prescribing information. Dosing for patients outside this age range is not covered.
Why is the pediatric option disabled for Psoriatic Arthritis?
The FDA-approved prescribing information for Stelara specifies dosing for adult Psoriatic Arthritis but does not provide a pediatric dosing regimen for this indication. The calculator reflects this by disabling the option.
How does the calculator handle weight conversion?
When "lbs" is selected, the tool converts the weight to kilograms using the standard conversion factor (1 lb ≈ 0.453592 kg) before applying the dosing rules.
What is the induction dose for a patient weighing 200 lbs with Ulcerative Colitis?
First, 200 lbs is approximately 90.7 kg. Since this is greater than 85 kg, the calculator will recommend the highest induction tier, which is a 520 mg IV infusion.
Does the calculator account for dose adjustments due to loss of response?
No. The tool calculates the standard, approved maintenance dose (90 mg every 8 weeks for CD/UC). The prescribing information notes that for CD/UC patients who lose response, dose frequency may be increased to every 4 weeks. This decision requires clinical judgment and is outside the scope of this standard calculator.
What is the recommended dose for a 12-year-old weighing 50 kg with Plaque Psoriasis?
For a pediatric patient weighing < 60 kg, the dose is 0.75 mg/kg. The calculator would compute 0.75 * 50 = 37.5 mg and display the recommended dose accordingly.
References
This tool and guide are based on information from the following high-authority sources. Always refer to the latest official documents for clinical decision-making.
- STELARA® (ustekinumab) Prescribing Information. U.S. Food and Drug Administration. Revised: 01/2024.
- Stelara (ustekinumab) Healthcare Professionals Site. Janssen Medical Information.
- Biologic Therapies for IBD. Crohn's & Colitis Foundation.
- Psoriasis Clinical Guidelines. American Academy of Dermatology.
