Stelara is a fully human immunoglobulin G1κ monoclonal antibody that binds specifically to the p40 subunit shared by IL-12 and IL-23, preventing their interaction with the IL-12Rβ1 receptor. This action inhibits downstream inflammatory pathways—particularly Th1 and Th17 cytokine responses—thereby reducing pathological inflammation.

Indications

Stelara is indicated for:

• Plaque psoriasis in adults (and in some regions, children);

• Psoriatic arthritis, alone or with methotrexate;

• Moderately to severely active Crohn’s disease;

• Moderately to severely active ulcerative colitis.
  For patients with Crohn’s or ulcerative colitis, it is used when they have failed conventional or biologic therapies.

Administration & Dosing

• Psoriasis / Psoriatic arthritis:

  • Adults ≤ 100 kg: 45 mg SC at Week 0, Week 4, then every 12 weeks.

  • Adults > 100 kg: 90 mg on same schedule. Pediatric dosing is weight-based as well

• Crohn’s disease / Ulcerative colitis:

  • Initial IV infusion (weight-based, ~6 mg/kg), followed by 90 mg SC at Week 8, then every 8 or 12 weeks depending on response and clinician judgment.

Onset & Outcomes

• For ulcerative colitis, many patients experience symptom relief by Week 8; about 40% maintain remission at 1 year, with evidence of reduced intestinal inflammation.

Side Effects & Precautions

Common adverse events include:

• Respiratory infections, headache, fatigue, injection site reactions, diarrhea (especially in IBD).
  Less common but serious risks include:

• Increased susceptibility to infections, potential reactivation of latent tuberculosis, hypersensitivity reactions, and possible elevation of cancer risks (e.g., skin cancer). Live vaccines should generally be avoided during treatment.