What is the appropriate dosing regimen for Stelara (ustekinumab)?

Stelara (Ustekinumab) Dosing

For adults with moderate-to-severe plaque psoriasis: use 45 mg subcutaneously at weeks 0 and 4, then every 12 weeks for patients ≤100 kg; use 90 mg subcutaneously at weeks 0 and 4, then every 12 weeks for patients >100 kg. 1, 2

Adult Dosing by Indication

Plaque Psoriasis

• Patients ≤100 kg: 45 mg subcutaneously initially and at week 4, then 45 mg every 12 weeks 1
• Patients >100 kg: 90 mg subcutaneously initially and at week 4, then 90 mg every 12 weeks 1
• Dose intensification option: For inadequate response, increase to 90 mg (instead of 45 mg) or shorten interval to every 8 weeks during maintenance 1

Psoriatic Arthritis

• Standard dosing: 45 mg subcutaneously at weeks 0 and 4, then every 12 weeks 1, 2
• Exception: Patients >100 kg with co-existent moderate-to-severe plaque psoriasis should receive 90 mg at weeks 0 and 4, then every 12 weeks 2

Crohn's Disease

• Induction (IV): Single weight-based intravenous dose 1, 2:
  • ≤55 kg: 260 mg (2 vials)
  • 56-85 kg: 390 mg (3 vials)

  • 85 kg: 520 mg (4 vials)

• Maintenance (subcutaneous): 90 mg subcutaneously 8 weeks after IV induction, then every 8 weeks 2, 3

Ulcerative Colitis

• Induction (IV): Same weight-based dosing as Crohn's disease 2, 4
• Maintenance (subcutaneous): 90 mg subcutaneously 8 weeks after IV induction, then every 8 weeks 2, 4

Pediatric Dosing (Ages 6-17 years)

Plaque Psoriasis and Psoriatic Arthritis

Dosing at weeks 0 and 4, then every 12 weeks 1, 2:

• <60 kg: 0.75 mg/kg (requires calculation from vial)
• 60-100 kg: 45 mg
• >100 kg: 90 mg (for psoriatic arthritis with co-existent moderate-to-severe plaque psoriasis)

The dosing frequency remains the same as adults (every 12 weeks maintenance) 1.

Key Clinical Considerations

When Standard Dosing Fails

For inadequate responders on standard every-12-week dosing in psoriasis: Increase to 90 mg (if on 45 mg) or shorten interval to every 8 weeks 1. This is a Grade A recommendation supported by the AAD-NPF guidelines.

For inflammatory bowel disease: While standard maintenance is every 8 weeks, recent prospective data show dose intensification to every 4-6 weeks is safe and effective for secondary loss of response, with 75% of CD patients and 71% of UC patients achieving steroid-free remission 5. However, this remains off-label.

Administration Pitfalls

• Do not handle needle cover if latex-sensitive - contains dry natural rubber 2
• Inject entire syringe contents to activate needle safety guard 2
• Rotate injection sites - use different anatomic locations (upper arms, gluteal regions, thighs, abdomen quadrants) 2
• For IV infusion (IBD): Must dilute in 250 mL normal saline, infuse over ≥1 hour, complete within 8 hours of preparation 2

Efficacy Data

The PHOENIX trials demonstrated PASI 75 rates at week 12 of 67.1% (45 mg) and 75.7% (90 mg) versus 3.7% for placebo 1. For Crohn's disease, response rates at week 6 were 34-56% versus 22-29% for placebo 3. For ulcerative colitis, clinical remission at week 44 was 38-44% versus 24% for placebo 4.

Safety Monitoring

• Screen for tuberculosis before initiating therapy 2
• Avoid in active infections - serious infections including pneumonia, gastroenteritis, and opportunistic infections have been reported 2, 6
• Monitor for malignancy - ustekinumab is an immunosuppressant 2
• Pregnancy: Safety unknown; antibodies are secreted in breast milk 1

The safety profile through 1 year in pooled IBD trials showed adverse event rates similar to placebo, with serious infection rates of 5.02 per 100 patient-years 6.