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Cited by 79Photodynamic Therapy Research StudiesNonmelanoma Skin Cancer StudiesPorphyrin Metabolism and Disorders

Topical Aminolevulinic Acid HCl Photodynamic Therapy

Ormrod, Douglas, Jarvis, Blair·2000·American Journal of Clinical Dermatology
DOI 10.2165/00128071-200001020-00009
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Abstract

Photodynamic therapy (PDT) is the treatment of tumors or dysplasic tissue with drugs that produce cytotoxic metabolites when exposed to light. Aminolevulinic acid HCl (5-aminolevulinic acid HCl; ALA) is a prodrug that is metabolized intracellularly to form the photosensitizing molecule protoporphyrin (PpIX). When PpIX is activated by light, cytotoxic reactive oxygen species and free radicals are generated. ALA can diffuse through skin and preferentially localizes in tumors and dysplasic tissue; subsequent exposure of PpIX-loaded tumor cells to light can destroy the tumor. After application of a 20% solution of ALA to actinic keratosis lesions of the head, PpIX (as measured by skin fluorescence) peaked 11 hours after treatment and the mean clearance half-life was 30 hours. In phase II trials 10 J/cm2 of blue light (wavelength = 417 nm) delivered at 10 mW/cm2 for 1000 seconds was found to provide maximal therapeutic effect on lesions of the head after treatment with 20% ALA. In phase III trials of ALA PDT in 241 patients with lesions of the head 72% of patients had a complete response to treatment at 12 weeks versus 20% of those treated with vehicle and light alone. Some of these patients had been re-treated at 8 weeks. In these trials 12% of ALA-treated patients and 37.5% of those receiving vehicle whose lesions had cleared at 8 weeks had relapsed at 12 weeks. When the total number of lesions were considered the recurrence rate was 5 and 27.9% for ALA- and vehicle-treated lesions, respectively. All patients reported some degree of burning or stinging during PDT but this usually subsided after irradiation was completed and was rarely treatment-limiting. Localized erythema and edema were also common. No other significant adverse effects were noted and treatment was generally well tolerated. A well designed dermal applicator ensured perilesional skin was spared collateral damage.

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Crossref · 10.2165/00128071-200001020-00009

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  • The recurrence rate between 8 and 12 weeks was 5% in all PDT-treated lesions versus 27.9% in lesions treated with vehicle and light only.

    “The recurrence rate between 8 and 12 weeks was 5% in all PDT-treated lesions. In contrast, 27.9% of lesions treated with vehicle and light only recurred during the same time period.”

    From 5-Aminolevulinic Acid as a Theranostic Agent for Tumor Fluorescence Imaging and Photodynamic Therapy (2023) · cites this paper as [16]

  • In phase III trials of 241 patients with head AK, topical ALA solution followed by blue light induced a 72% complete response rate at 12 weeks, versus 20% in patients treated with vehicle and light only.

    “In phase III trials of 241 patients with head AK, topical application of ALA solution on the lesion area followed by blue light treatment induced a 72% complete response rate at 12 weeks after PDT, whereas only a 20% response rate was seen in patients treated with vehicle and light only [16].”

    From 5-Aminolevulinic Acid as a Theranostic Agent for Tumor Fluorescence Imaging and Photodynamic Therapy (2023) · cites this paper as [16]

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Authors
Ormrod, D., & Jarvis, B.
Corresponding author
Ormrod, Douglas
Venue
American Journal of Clinical Dermatology
Publisher
Springer Science and Business Media LLC
Published
2000-03
Volume
1
Issue
2
Pages
133-139
ISSN
1175-0561 (ISSN-L)
DOI
10.2165/00128071-200001020-00009
OpenAlex
W2090130916
Cited by
79
References
39
Citations by year
2025: 1 · 2024: 1 · 2023: 2 · 2022: 1 · 2021: 1 · 2018: 2 · 2017: 1 · 2016: 1 · 2014: 3 · 2013: 4 · 2012: 3
FWCI
6.74
Type
journal article
Language
en
Open access
closed
Locations
  • American Journal of Clinical Dermatology (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Photodynamic Therapy Research Studies
  • Health Sciences › Medicine › Epidemiology › Nonmelanoma Skin Cancer Studies
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Porphyrin Metabolism and Disorders
Keywords
5-aminolevulinic acid, photodynamic therapy, actinic keratosis, protoporphyrin IX, blue light, topical treatment, skin fluorescence, treatment response, recurrence, adverse effects
MeSH terms
Administration, Topical, Aminolevulinic Acid, Humans, Photochemotherapy, Photosensitizing Agents, Clinical Trials, Phase II as Topic, Clinical Trials, Phase III as Topic

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