Update on psoriasis

Psoriasis remains a complex chronic inflammatory disease requiring a diverse therapeutic armamentarium. Despite the widespread use of biologics, phototherapy continues to be discussed as a viable option. Narrowband UVB (NB-UVB) therapy, distinct from broadband UVB or PUVA, has well-recognised limitations, particularly in difficult-to-treat areas such as the scalp, nails, palms, soles, and genital regions, and it does not address systemic comorbidities. It is also time-intensive, as patients require treatment sessions two to three times per week. Nevertheless, NB-UVB remains an effective and safe intervention. It is approximately ten times less costly than biologic or small molecule therapies, can be rapidly effective in acute presentations such as guttate psoriasis, and does not require laboratory monitoring. Moreover, it can be combined with other therapies and administered intermittently rather than continuously. Interestingly, quality-of-life outcomes have been shown to surpass those achieved with adalimumab, potentially due to the supportive role of repeated patient–care team interactions. These findings reinforce the continued relevance of phototherapy as a first-line option in selected patients.

Recent therapeutic advances also include icotrokinra, a novel oral peptide selectively inhibiting the IL-23 receptor. This agent addresses the unmet need for an oral therapy with biologic-like efficacy and safety in moderate-to-severe plaque psoriasis. Results from two phase III trials demonstrated significantly higher rates of complete or near-complete clearance compared with placebo and deucravacitinib, with a safety profile comparable to placebo. No unexpected safety signals emerged over 24 weeks, making icotrokinra a promising addition to psoriasis management.

Lifestyle factors remain central to disease modulation, particularly weight control, which shows the strongest evidence for clinical benefit. In obese patients, weight loss exceeding 5% can improve PASI scores significantly. Recent studies highlighted dietary influences: epidemiological data from the UK Biobank revealed that patients with psoriasis and comorbidities consumed more processed meat, sodium, and free sugars, with lower intake of whole grains. The APPLE study confirmed processed meat as a positive predictor of severity, while nuts and legumes were negatively associated. The MET-RED-P trial demonstrated that both mediterranean and time-restricted eating improved symptoms and dermatology-related quality of life, with the mediterranean diet favouring well-being and time-restricted eating supporting weight loss. Although promising, dietary interventions still lack sufficient evidence to reach guideline-level recommendations, underscoring the need for large RCTs.

Finally, the emerging role of GLP-1RAs in dermatology warrants attention. While these agents are established in obesity and type 2 diabetes, their potential anti-inflammatory effects in psoriasis remain under investigation. Given the strong association between psoriasis, obesity, and metabolic dysfunction, GLP-1 receptor agonists may offer dual benefits beyond weight loss. Future studies should explore their efficacy in psoriasis, ideally stratified by metabolic profile, insulin resistance and obesity phenotype.