What is the recommended dosage and treatment protocol for Tremfya (guselkumab) in patients with moderate to severe plaque psoriasis and psoriatic arthritis?

Tremfya (Guselkumab) Dosage and Treatment Protocol for Moderate to Severe Plaque Psoriasis and Psoriatic Arthritis

For patients with moderate to severe plaque psoriasis and psoriatic arthritis, Tremfya (guselkumab) should be administered as 100 mg subcutaneous injections at Week 0, Week 4, and every 8 weeks thereafter. 1

Recommended Dosage Regimen

For Plaque Psoriasis:

• Initial dose: 100 mg subcutaneous injection at Week 0
• Second dose: 100 mg subcutaneous injection at Week 4
• Maintenance: 100 mg subcutaneous injection every 8 weeks thereafter 2, 1

For Psoriatic Arthritis:

• Initial dose: 100 mg subcutaneous injection at Week 0
• Second dose: 100 mg subcutaneous injection at Week 4
• Maintenance: 100 mg subcutaneous injection every 8 weeks thereafter 1
• May be administered alone or in combination with conventional disease-modifying antirheumatic drugs (e.g., methotrexate) 1

Pre-Treatment Evaluation

Before initiating Tremfya, the following evaluations are recommended:

• Tuberculosis (TB) screening (required) 2, 1
• Complete blood count (CBC) 2
• Liver function tests (LFT) 2
• Hepatitis profile 2
• Complete all age-appropriate vaccinations according to current immunization guidelines 1

Administration Guidelines

• Tremfya is available as prefilled pen, One-Press injector, and prefilled syringes 1
• Allow medication to reach room temperature (30 minutes) before injection without removing the needle cap 1
• Injection sites: front of thighs, lower abdomen (except 2 inches around navel), or back of upper arms (healthcare professional or caregiver only) 1
• Avoid injecting into areas where skin is tender, bruised, red, hard, thick, scaly, or affected by psoriasis 1

Monitoring and Assessment of Response

• Definitive response to Tremfya should be assessed after 12 weeks of continuous therapy 2
• Consider the addition of other modalities (topical corticosteroids, vitamin D analogues, methotrexate, or ultraviolet B light) in partially responding patients 2
• Periodic history and physical examination are recommended while on treatment 2
• Consider yearly TB screening and periodic CBC and LFT 2

Efficacy Data

Guselkumab has demonstrated superior efficacy compared to placebo and adalimumab in clinical trials:

• In the VOYAGE 2 trial, 70% of patients receiving guselkumab achieved PASI 90 at week 16 compared to 46.8% with adalimumab and 2.4% with placebo 2
• For patients who were non-responders to adalimumab and switched to guselkumab, 66.1% achieved PASI 90 at week 48 2
• In psoriatic arthritis trials, 58% of guselkumab-treated patients achieved ACR20 response at week 24 compared to 18% with placebo 3

Safety Considerations

• Guselkumab has a favorable safety profile with long-term treatment 4
• Most common adverse event is infection (16% in guselkumab-treated patients) 3
• No evidence that IL-23 antagonists used as monotherapy increase the risk of solid tumor or lymphoreticular malignancy 2
• Use caution in patients with pre-existing immunosuppression-related conditions 2
• Pregnancy category B 2

Special Populations and Considerations

• If a dose is missed, administer as soon as possible and resume regular scheduled dosing thereafter 1
• For patients who have previously failed TNF inhibitors, guselkumab remains an effective option, with 59% achieving ACR20 at week 24 in the DISCOVER-1 trial 5
• Guselkumab has shown effectiveness in real-world settings, including in patients with high BMI (≥30 kg/m²) 6

Common Pitfalls to Avoid

1. Inadequate pre-treatment screening: Always screen for TB and complete appropriate laboratory tests before initiating therapy
2. Premature efficacy assessment: Wait at least 12 weeks before determining treatment response
3. Improper injection technique: Ensure proper training on subcutaneous injection technique
4. Storage issues: Keep Tremfya refrigerated until 30 minutes before use
5. Discontinuing without consultation: Advise patients not to discontinue or modify treatment without consulting their dermatologist

Guselkumab represents an effective treatment option with a favorable benefit-risk profile for patients with moderate-to-severe plaque psoriasis and active psoriatic arthritis, with the convenience of maintenance dosing every 8 weeks.