What is a detailed prescription for a patient with moderate-to-severe plaque psoriasis, including biologic (Secukinumab) dosing, dispensing, storage, adjunctive topical calcipotriene/betamethasone therapy, baseline laboratory screening, monitoring schedule, and an alternative biologic (Guselkumab) if biologic therapy is contraindicated?

Detailed Prescription for Moderate-to-Severe Plaque Psoriasis

Primary Biologic Therapy: Secukinumab (Cosentyx®)

For moderate-to-severe plaque psoriasis, prescribe secukinumab 300 mg subcutaneously at weeks 0,1,2,3, and 4, followed by 300 mg every 4 weeks as maintenance therapy. 1, 2

Exact Prescription Details

Medication: Secukinumab (Cosentyx®) 300 mg/2 mL subcutaneous injection

Loading Dose Regimen:

• 300 mg (two 150 mg injections OR one 300 mg/2 mL UnoReady pen) subcutaneously at Week 0
• 300 mg subcutaneously at Week 1
• 300 mg subcutaneously at Week 2
• 300 mg subcutaneously at Week 3
• 300 mg subcutaneously at Week 4

Maintenance Dose:

• 300 mg subcutaneously every 4 weeks starting at Week 8 1, 2

Dispensing:

• Dispense #20 prefilled syringes (150 mg each) OR #10 UnoReady pens (300 mg/2 mL each) for initial 12-week period
• Refills: Dispense #2 syringes or #1 pen every 4 weeks for maintenance

Storage: Refrigerate at 2-8°C (36-46°F). May be kept at room temperature up to 25°C (77°F) for up to 4 days. Protect from light. Do not freeze or shake. 2

Administration: Self-administered subcutaneous injection. Rotate injection sites (thigh, abdomen, upper arm). 1

Dosing Optimization Considerations

The 300 mg dose is superior to 150 mg and should be the standard dose 1. Do not reduce to every 6 weeks dosing - this fails to maintain PASI 90 response (74.9% vs 85.7% with every 4 weeks) 3. For patients ≥90 kg who fail to achieve PASI 90 by week 24, consider intensifying to 300 mg every 2 weeks 3.

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Adjunctive Topical Therapy: Calcipotriene/Betamethasone

Add calcipotriene 0.005%/betamethasone dipropionate 0.064% foam to accelerate clearance and manage residual plaques. 4, 5, 6

Exact Prescription Details

Medication: Calcipotriene 0.005%/Betamethasone dipropionate 0.064% (Cal/BD) aerosol foam

Dosing Regimen:

• Apply once daily to affected areas for first 4 weeks
• Then reduce to every other day for weeks 5-12
• Maximum duration: 12 weeks per treatment course 4, 5

Dispensing:

• Dispense #2 canisters (60 g each) initially
• Refills: 1 refill

Application: Apply thin layer to psoriatic plaques. Avoid face, groin, and axillae unless specifically directed. Wash hands after application.

Rationale: Combination therapy with biologics improves outcomes - 56% of patients with residual disease (3-8% BSA) after ≥24 weeks of biologic therapy achieved ≤1% BSA with adjunctive Cal/BD foam 5. Recent data shows this combination optimizes lesion clearance when used with secukinumab 6, 7.

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Baseline Laboratory Screening

Before initiating secukinumab, obtain the following mandatory screening tests: 1

1. Tuberculosis screening:

   • Tuberculin skin test (PPD) OR interferon-gamma release assay (QuantiFERON-TB Gold or T-SPOT.TB)
   • Chest X-ray if TB screening positive or high clinical suspicion

2. Hepatitis B screening:

   • Hepatitis B surface antigen (HBsAg)
   • Hepatitis B core antibody (anti-HBc)
   • If positive, obtain HBV DNA and consult infectious disease

3. Complete blood count (CBC) with differential

4. Complete metabolic panel (CMP) including liver function tests

5. Pregnancy test for women of childbearing potential

Absolute Contraindications

• History of allergic reaction to secukinumab or vehicle 1
• Active untreated tuberculosis 1

Relative Contraindications

• Untreated hepatitis B infection (requires infectious disease consultation) 1
• Active infection or sepsis (defer until resolved) 1
• History of lymphoreticular malignancy 1

Critical Pitfall: Do not initiate therapy with active infection. Treatment can restart after complete resolution of symptoms and completion of any antibiotic course 1.

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Monitoring Schedule

Week 12 Assessment (Primary Response Evaluation)

• PASI score
• Body surface area involvement
• Physician Global Assessment (PGA)
• CBC, CMP
• Assess for adverse events

Week 24 Assessment

• PASI score (target: PASI 90 response)
• If PASI <90 and patient ≥90 kg: consider increasing to every 2 weeks 3
• CBC, CMP

Ongoing Monitoring (Every 12-16 weeks)

• Clinical assessment of disease activity
• CBC, CMP every 3-6 months
• Monitor for infections, inflammatory bowel disease symptoms
• Annual TB screening in high-risk patients 1

Safety Monitoring

• Infections: Monitor for signs/symptoms at each visit. Temporarily discontinue for febrile illness requiring antibiotics 1
• Inflammatory bowel disease: Question about new-onset diarrhea, abdominal pain, or rectal bleeding at each visit 1
• Neutropenia: Monitor CBC - secukinumab may cause grade ≤2 neutropenia 1

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Alternative Biologic: Guselkumab (If Secukinumab Contraindicated)

If IL-17 inhibitors are contraindicated (e.g., inflammatory bowel disease, recurrent Candida infections), prescribe guselkumab 100 mg subcutaneously at weeks 0,4, and every 8 weeks thereafter. 1, 8

Exact Prescription Details

Medication: Guselkumab (Tremfya®) 100 mg/mL subcutaneous injection

Dosing Regimen:

• 100 mg subcutaneously at Week 0
• 100 mg subcutaneously at Week 4
• 100 mg subcutaneously every 8 weeks thereafter 1

Dispensing:

• Dispense #3 prefilled syringes (100 mg/mL each) for initial 12-week period
• Refills: Dispense #1 syringe every 8 weeks

Storage: Refrigerate at 2-8°C (36-46°F). May be kept at room temperature up to 25°C (77°F) for up to 24 hours. Protect from light.

Administration: Self-administered subcutaneous injection. Rotate injection sites.

Advantages of Guselkumab

• Superior to adalimumab (PASI 90: 73.3% vs 49.7% at week 16) 8
• Superior to secukinumab at week 48 (ECLIPSE trial) 8
• Less frequent dosing (every 8 weeks) may improve adherence 1
• Effective for scalp, nail, and palmoplantar psoriasis 1
• Preferred over secukinumab if inflammatory bowel disease present or history of recurrent Candida infections 1

Baseline Screening for Guselkumab

Same as secukinumab: TB screening, hepatitis B screening, CBC, CMP, pregnancy test 1

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Treatment Failure Management

If Loading Doses Interrupted

Repeat loading doses if: 1

• Patient is flaring AND/OR
• More than 3-4 half-lives have passed since previous dose (secukinumab half-life: 22-31 days; approximately 12-16 weeks) 2

Primary Failure (No Response by Week 12)

• Verify adherence and proper injection technique
• Consider dose intensification to every 2 weeks if ≥90 kg 3
• Switch to different mechanism: guselkumab 100 mg every 8 weeks 8, 9

Secondary Failure (Loss of Response After Initial Success)

• First-line: Switch to ixekizumab (within-class switch shows 66.7% PASI 75 at week 12) 9
• Second-line: Switch to guselkumab (across-class switch) 9
• Consider checking for anti-drug antibodies (rare with secukinumab: <0.4%) 1

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Special Populations

Pregnancy and Lactation

• Animal studies show no harm to developing fetus 1
• No human pregnancy data available 1
• Acceptable for men attempting conception 1
• Presence in breast milk unknown - discuss risks/benefits 1

Psoriatic Arthritis

Secukinumab is FDA-approved for psoriatic arthritis and provides dual benefit for skin and joint disease 1. If patient develops joint symptoms, continue secukinumab rather than switching to ustekinumab (which is less effective for preventing joint destruction) 1.

Patients ≥90 kg

Standard 300 mg every 4 weeks dosing initially. If PASI 90 not achieved by week 24, intensify to 300 mg every 2 weeks (57.1% achieve PASI 90 vs 40% with every 4 weeks) 3.

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Patient Education Points

1. Injection technique: Demonstrate proper subcutaneous injection, site rotation, and disposal of sharps
2. Infection precautions: Report fever, persistent cough, or signs of infection immediately
3. Adherence: Emphasize importance of maintaining every 4-week schedule - do not extend intervals 3
4. Realistic expectations: Peak response typically by week 12-16; 82% achieve PASI 75 with 300 mg dose 1, 10
5. Topical adjunct: Continue Cal/BD foam as prescribed to optimize clearance 5, 6
6. Live vaccines: Avoid during treatment; complete vaccinations before starting therapy 2