5% KOH Solution vs. Placebo and Diclofenac Gel for the Treatment of Actinic Keratosis
KOHDIAK
Prospective, Three-armed, Randomised, Double-blind Study to Evaluate the Efficacy and Safety of the Treatment of Mild and Moderate Actinic Keratosis With a 5% Potassium Hydroxide Solution (Solcera, Medical Device) Versus Placebo and Investigator-blinded Comparison With 3% Diclofenac Gel (Solaraze, Medicinal Product) (Regulated by the Laws for Both Medical Devices and Medicinal Products)
1 other identifier
interventional
631
1 country
18
Brief Summary
The KOHDIAK study is a prospective, three-armed, randomised, double-blind study to evaluate the efficacy and safety of the treatment of mild and moderate actinic keratosis with a 5% potassium hydroxide solution (Solcera, medical device) versus placebo and investigator-blinded comparison with 3% diclofenac gel (Solaraze, medicinal product). It is performed in accordance with both the laws in force for clinical trials with medical devices and those with medicinal products.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_3
Started Oct 2020
18 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
Click on a node to explore related trials.
Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
September 3, 2020
CompletedFirst Posted
Study publicly available on registry
September 17, 2020
CompletedStudy Start
First participant enrolled
October 14, 2020
CompletedPrimary Completion
Last participant's last visit for primary outcome
January 24, 2023
CompletedStudy Completion
Last participant's last visit for all outcomes
January 24, 2023
CompletedMarch 5, 2024
February 1, 2024
2.3 years
September 3, 2020
March 4, 2024
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Treatment success
Treatment success, defined as complete, dermatoscopically confirmed remission of all initial actinic keratosis (AK) lesions identified at treatment start that have been treated with the investigational product ("Complete Clearance")
At the control visit at the end of treatment ("EOT", i.e. for Solcera/Placebo at the end of cycle 1, 2 or 3 (each cycle is 56 days, number of cycles depends on course of remission), for Solaraze day 60)
Secondary Outcomes (21)
Treatment success
For Solaraze at day 90
(Healing) status of AK lesions
At all control/follow-up visits with evaluation of lesions (i.e. for Solcera/Placebo 8 weeks (+ potentially 16 weeks) and 24 weeks after treatment start; for Solaraze Day 30, Day 60, Day 90, 24 weeks)
Overall number of AK lesions
At all control/follow-up visits with evaluation of lesions (i.e. for Solcera/Placebo 8 weeks (+ potentially 16 weeks) and 24 weeks after treatment start; for Solaraze Day 30, Day 60, Day 90, 24 weeks)
Mean size of AK lesions
At all control/follow-up visits with evaluation of lesions (i.e. for Solcera/Placebo 8 weeks (+ potentially 16 weeks) and 24 weeks after treatment start; for Solaraze Day 30, Day 60, Day 90, 24 weeks)
Treatment success
At all control/follow-up visits with evaluation of lesions (i.e. for Solcera/Placebo 8 weeks (+ potentially 16 weeks) and 24 weeks after treatment start; for Solaraze Day 30, Day 60, Day 90, 24 weeks)
- +16 more secondary outcomes
Study Arms (3)
Solcera
EXPERIMENTALPlacebo
PLACEBO COMPARATORSolaraze
ACTIVE COMPARATORInterventions
Twice daily application for a duration of 4 weeks followed by another 4 weeks without treatment (up to 2 potential repetitions of this 8-week cycle)
Twice daily application for a duration of 4 weeks followed by another 4 weeks without treatment (up to 2 potential repetitions of this 8-week cycle)
Eligibility Criteria
You may qualify if:
- Age ≥ 18 years and \< 90 years
- Actinic keratosis grade I (mild) or II (moderate) according to the definition by Olsen with palpable or clinically/dermatoscopically apparent keratosis
- Either lesions being well accessible/treatable by the patient or presence of a second person to do the daily applications
- Written informed consent by the patient
You may not qualify if:
- Number of initial lesions to be treated ≥ 6
- Overall size of the area to be treated \> 25 cm2
- Size (maximum diameter) of single lesion to be treated \> 20 mm
- Lesions in close proximity to the eyes, eyelids, nostrils, mouth or mucosal tissue
- Need for topical treatment of cancerous area
- Presence of a relapsing, persistent, indurated, thickened, painful, bleeding, ulcerated and/or rapidly growing lesion
- Existing skin cancer (all forms of skin cancer incl. basal-cell carcinoma and squamous cell carcinoma) in the area to be treated in this study
- Dermal injuries, skin infection or exfoliative dermatitis in the area to be treated in this study
- Other skin diseases in the area to be treated in this study that affect the diagnostic assessment
- Pharmacological or physical local therapy of actinic keratosis (or application of the active ingredients used in the pharmacological therapy) in the area to be treated in this study during the last 4 weeks
- Primary or secondary immunodeficiency
- Treatment with interferons, interferon inducers, immunomodulators or systemic corticosteroids during the last 4 weeks
- Treatment with oral isotretinoin during the last 6 months
- Intracranial bleeding in the medical history or generally increased primary bleeding tendency
- Known intolerance/hypersensitivity to one of the ingredients of the investigational products, especially to diclofenac, parabens or benzyl alcohol as well as to NSAIDs, in particular acetylsalicylic acid
- +9 more criteria
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (18)
Hautmedizin Bad Soden
Bad Soden, 65812, Germany
MVZ - Dermatologisches Zentrum Bonn GmbH
Bonn, 53111, Germany
Hautzentrum Köln
Cologne, 50996, Germany
Proderma Studienzentrum
Dülmen, Germany
Hautarztpraxis Falkensee
Falkensee, 14612, Germany
Hautzentrum Südbaden
Freiburg im Breisgau, Germany
Hautarztzentrum Hamm
Hamm, Germany
Praxis Dres. Med. Markus Kaspari und Florian Schenk
Hanover, 30159, Germany
Durani Cosmetics GmbH
Heidelberg, Germany
Hautarztpraxis Ibbenbüren
Ibbenbueren, Germany
Praxis Dres. K.-H. Vehring/U. Amann
Lingen, 49809, Germany
Zentderma GBR
Mönchengladbach, 41061, Germany
Haut- und Laserzentrum
Potsdam, Germany
Hautarztpraxis Asefi/Sadjadi
Simmern, Germany
Hautarztpraxis Leitz und Kollegen
Stuttgart, Germany
Hautarztpraxis Vilshofen
Vilshofen, 94474, Germany
Centroderm GmbH
Wuppertal, 42287, Germany
Hautzentrum Wuppertal
Wuppertal, 42349, Germany
Related Publications (1)
Reinhold U, Leitz N, Dominicus R, Szabo EL, Dirschka T, Popp G, Fischer TC, Adamini N, Ostendorf R, Asefi M, Durani H, Holting T, Amann U, Kreuziger F, Assmann T, Bruning H, Freitag L, Hoffmann K, Gedschold R. KOH 5% solution versus diclofenac 3% for the treatment of actinic keratosis - Results from a three-armed RCT. J Eur Acad Dermatol Venereol. 2025 Sep 25. doi: 10.1111/jdv.70069. Online ahead of print.
PMID: 40996107DERIVED
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Intervention Hierarchy (Ancestors)
Study Officials
- STUDY DIRECTOR
Uwe Reinhold, Prof.
MVZ - Dermatologisches Zentrum Bonn GmbH
Study Design
- Study Type
- interventional
- Phase
- phase 3
- Allocation
- RANDOMIZED
- Masking
- DOUBLE
- Who Masked
- PARTICIPANT, INVESTIGATOR
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
September 3, 2020
First Posted
September 17, 2020
Study Start
October 14, 2020
Primary Completion
January 24, 2023
Study Completion
January 24, 2023
Last Updated
March 5, 2024
Record last verified: 2024-02
Data Sharing
- IPD Sharing
- Will not share