{
  "abstract": "Introduction: The global burden of atopic dermatitis (AD) will continue to rise in the coming two decades, underscoring the need for affordable and globally accessible therapies given restricted access to high-cost medications in many regions. The study aimed to evaluate the efficacy of a novel phototherapy-based regimen as an add-on therapy, together with vitamin D supplementation, on long-term disease control in AD. Methods: The PRADA trial combined two independent randomizations within the same population: an open-label, crossover comparison of narrowband ultraviolet B (NB-UVB) phototherapy versus observation, and a double-blind, parallel-group comparison of vitamin D versus placebo, both superimposed on standard topical anti-inflammatory treatments (TAT). It was conducted between 2015 and 2023 across 16 French hospital centers. The trial included patients aged ≥ 15 years with moderate-to-severe (IGA > 2) AD and with fewer than 100 lifetime phototherapy sessions. The primary outcome was a hierarchical composite endpoint based on: (1) repeated measures of Patient-Oriented SCORing Atopic Dermatitis (PO-SCORAD) severity score over 1 year; and (2) the cumulative use of TAT from October to March. Results: A total of 53 participants were allocated to the vitamin D (26 received NB-UVB during the first period), and 57 to the placebo (27 received NB-UVB during the first period). A total of 93 participants were available for the main analysis for the primary endpoint. Vitamin D was significantly associated with lower PO-SCORAD scores compared with placebo (mean [95% CI] difference -5.6 [-12.1 to -1.78]), however, this effect size remained below the prespecified minimum clinically important difference (nine points). NB-UVB showed no significant effect on PO-SCORAD scores (mean difference: 1.25 [-3.90 to 1.40]). Adverse event incidence was 0.33 per 100 patient-months, mainly nonserious photosensitivity reactions (n = 38). Conclusions: In the PRADA trial (underpowered due to a recruitment short fall), NB-UVB phototherapy showed no clinically meaningful benefit on the long-term control of moderate-to-severe AD. The observed benefit of vitamin D supplementation on PO-SCORAD, although statistically significant, did not reach the threshold for clinical relevance. Trial registration: ClinicalTrials.gov Identifier: NCT02537509.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 17,
  "authors": [
    {
      "name": "Catherine Droitcourt"
    },
    {
      "name": "Sébastien Barbarot"
    },
    {
      "name": "Valérie Visseiche"
    },
    {
      "name": "Annabel Maruani"
    },
    {
      "name": "Monica Dinulescu"
    },
    {
      "name": "Laure Darrieux"
    },
    {
      "name": "Laurent Misery"
    },
    {
      "name": "Emilie Brenaut"
    },
    {
      "name": "Angèle Soria"
    },
    {
      "name": "Annie Vermersch"
    },
    {
      "name": "Hervé Maillard"
    },
    {
      "name": "Julien Seneschal"
    },
    {
      "name": "Alain Taieb"
    },
    {
      "name": "Cécile Chabbert"
    },
    {
      "name": "Henri Adamski"
    },
    {
      "name": "Alain Dupuy"
    },
    {
      "name": "Emmanuel Oger"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/ehkszphvx7d2s.bib",
  "cited_by": 0,
  "doi": "10.1007/s13555-026-01914-8",
  "fulltext_url": null,
  "id": "ehkszphvx7d2s",
  "issns": [
    "2193-8210",
    "2193-8210"
  ],
  "landing_url": "https://u-bordeaux.hal.science/hal-05771391v1",
  "language": "en",
  "licence": "CC-BY-NC-4.0",
  "licence_label": "CC BY-NC 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "hal",
      "0.sdv"
    ],
    [
      "hal",
      "1.sdv.imm"
    ],
    [
      "openalex",
      "2708|Dermatology and Skin Diseases"
    ]
  ],
  "openalex": "W7212296983",
  "pdf_url": "https://u-bordeaux.hal.science/hal-05771391/document",
  "pmcid": null,
  "pmid": "42728529",
  "published": "2026-09-11",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/ehkszphvx7d2s.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:44Z",
      "native_id": "hal-05771391",
      "source": "hal",
      "url": "https://u-bordeaux.hal.science/hal-05771391v1"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "hal:1.sdv.imm",
      "subfield": "immunology"
    }
  ],
  "title": "A New Phototherapy Regimen Coupled with Oral Vitamin D Supplementation, for the Long-Term Control of Atopic Dermatitis: A French Multicenter, Randomized, Crossover, Pragmatic Trial",
  "title_text": "A New Phototherapy Regimen Coupled with Oral Vitamin D Supplementation, for the Long-Term Control of Atopic Dermatitis: A French Multicenter, Randomized, Crossover, Pragmatic Trial",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:17:44Z",
  "url": "https://research.draconitic.com/paper/ehkszphvx7d2s",
  "venue": "Dermatology and Therapy",
  "versions": []
}