What is the recommended loading dose for Tremfaya (guselkumab) in an adult patient with moderate to severe plaque psoriasis?

Tremfaya Loading Dose for Moderate to Severe Plaque Psoriasis

The recommended loading dose for Tremfaya (guselkumab) is 100 mg by subcutaneous injection at week 0 and week 4, followed by maintenance dosing every 8 weeks thereafter. 1, 2

Standard Dosing Regimen

The FDA-approved and guideline-recommended dosing schedule for guselkumab in adults with moderate-to-severe plaque psoriasis is straightforward:

• Week 0: 100 mg subcutaneous injection 1, 2
• Week 4: 100 mg subcutaneous injection 1, 2
• Week 12 and every 8 weeks thereafter: 100 mg subcutaneous injection 1, 2

This dosing regimen received a Grade A recommendation from the American Academy of Dermatology and National Psoriasis Foundation, representing the highest level of evidence-based support. 1, 3

Administration Details

• Route: Subcutaneous injection that can be self-administered by the patient after proper training, or administered by a healthcare professional 1, 2
• Injection sites: Front of thighs, lower abdomen (avoiding 2 inches around navel), or back of upper arms (healthcare professional only) 2
• Preparation: Remove from refrigerator 30 minutes before injection to reach room temperature 2

Clinical Context and Efficacy

The loading dose strategy (weeks 0 and 4) followed by every-8-week maintenance was established through pivotal VOYAGE 1 and VOYAGE 2 trials, which demonstrated:

• 70.0-73.3% of patients achieved PASI 90 at week 16 3
• Superior efficacy compared to adalimumab (70.0% vs 46.8% achieving PASI 90) 1, 3
• Sustained long-term responses maintained for up to 5 years 3

Response Assessment Timeline

Definitive response to guselkumab should be assessed after 12 weeks of continuous therapy (which corresponds to 3 doses: weeks 0,4, and 12). 1

For partial responders at 12 weeks, consider adding adjunctive therapies such as topical corticosteroids, vitamin D analogues, methotrexate, or ultraviolet B light rather than immediately discontinuing. 1

Important Dosing Considerations

If Doses Are Missed

If a dose is missed, administer it as soon as possible, then resume the regular scheduled dosing interval. 2

Repeating loading doses after treatment interruption: Consider repeating the week 0 and week 4 loading doses if the patient is experiencing a flare and/or if more than 3-4 half-lives have passed since the previous dose (guselkumab half-life is approximately 15-18 days, so this would be roughly 45-72 days). 1

Special Populations

The same 100 mg loading dose regimen (weeks 0,4, then every 8 weeks) applies to:

• Scalp psoriasis 1
• Nail psoriasis 1
• Plaque-type palmoplantar psoriasis 1

Pre-Treatment Requirements

Before initiating the loading dose:

• Evaluate for tuberculosis infection 2
• Complete age-appropriate vaccinations according to current immunization guidelines 2

Common Pitfalls to Avoid

• Do not confuse with other IL-23 inhibitors: Tildrakizumab uses a different schedule (weeks 0,4, then every 12 weeks), and risankizumab uses yet another schedule. 1
• Do not weight-adjust the dose: Unlike ustekinumab, guselkumab is dosed at 100 mg regardless of body weight for plaque psoriasis. 1, 2
• Do not discontinue prematurely: Allow the full 12-week assessment period (3 doses) before determining treatment failure. 1