Biologics, Phototherapy and Newer Dermatological Therapeutics MCQs

Dermatology · 15 free questions with answers & explanations.

1. Dupilumab is approved for moderate-to-severe atopic dermatitis. Its mechanism of action is:
2. Secukinumab and ixekizumab are anti-IL-17A biologics approved for psoriasis. Compared to anti-TNF biologics (adalimumab), they are CONTRAINDICATED in patients with:
3. Narrow-band UVB (NB-UVB, 311–313 nm) has largely replaced broadband UVB for phototherapy. NB-UVB is the first-line phototherapy for all of the following EXCEPT:
4. Guselkumab and risankizumab represent the newest class of biologics for plaque psoriasis. Their mechanism targets:
5. A 42-year-old with moderate-to-severe plaque psoriasis (PASI 18, DLQI 14) fails two conventional systemic agents. You initiate a biologic. Secukinumab acts specifically by blocking which cytokine that is the primary downstream effector in psoriasis pathogenesis?
6. Dupilumab, approved for moderate-to-severe atopic dermatitis, works by blocking which receptor signalling pathway?
7. In PUVA therapy for psoriasis, 8-methoxypsoralen (8-MOP) acts on DNA after UVA activation. Which precise photochemical reaction is responsible for its therapeutic effect?
8. Narrow-band UVB (NB-UVB, 311–313 nm) has largely replaced broadband UVB for vitiligo and psoriasis treatment. The main advantage of NB-UVB over broadband UVB in clinical practice is:
9. A 35-year-old man with moderate-to-severe plaque psoriasis (PASI 22, DLQI 18) is started on secukinumab. After 16 weeks (loading dose + maintenance), PASI 90 response is achieved. Secukinumab's mechanism of action is:
10. PUVA phototherapy for psoriasis uses 8-methoxypsoralen (8-MOP) and UVA radiation. The photobiological mechanism by which psoralen + UVA achieves therapeutic effect in psoriasis is:
11. Dupilumab is approved for moderate-to-severe atopic dermatitis in adults and children ≥6 months. It works by blocking the shared receptor subunit for IL-4 and IL-13. Which specific receptor subunit does dupilumab target?
12. IL-17A is targeted by which biologic used in moderate-to-severe psoriasis, and what is the characteristic adverse effect specific to this class (IL-17 inhibitors)?
13. Which of the following correctly describes the mechanism of action and primary indication of dupilumab in dermatology?
14. Narrow-band UVB (NB-UVB) phototherapy at 311 nm is preferred over broadband UVB for which specific reason?
15. A 55-year-old woman with moderate-to-severe atopic dermatitis has failed topical steroids and two immunosuppressants. She is started on abrocitinib. What is the mechanism of action of this drug?