Objective light exposure measurements and circadian rhythm in patients with erythropoietic protoporphyria: A case-control study.

Wensink D, Wagenmakers MAEM, Qi H, Wilson JHP, Langendonk JG

Molecular genetics and metabolism2 Jan 2022Cited by 10 (Europe PMC)

PMID35034844DOI10.1016/j.ymgme.2021.12.017PepBankPUB-35034844

Publisher page PubMedAsk about this study

Summary

The text of this summary is not shown here, because the article license does not allow reuse. Read it at the source (opens in a new tab)

Text rights: Publisher copyright. Results still quote short attributed sentences.

Results from this study5

4 results from studies that gave the peptide. 4 results from people.

01HumanObservational studyEfficacy outcome
Mean bedtime was 23:45 in EPP patients off treatment, 23:02 in controls and 23:14 in EPP patients on afamelanotide (p < 0.0001).
In plain wordsBedtime was 23:45 in EPP patients off treatment, 23:02 in healthy controls and 23:14 in EPP patients on afamelanotide.
Peptide
Melanotan I (afamelanotide)
Outcome
MixedBedtime
Study
n = 49
Comparator
EPP patients off treatment and controls
Outcome group
Sleep · Sleep
Studied dose
Dose not stated
Source sentences
Summary
Bedtime differed between EPP patients off treatment, controls and EPP patients on treatment (23:45 h ± 1:51 versus 23:02 ± 1:41 and 23:14 ± 1:29, respectively; p < 0.0001).
2 context sentences(design, population, supporting numbers)
Summary · context
Adult EPP patients visiting the Porphyria Center Rotterdam of the Erasmus MC were included in this single-center longitudinal case-control open-label intervention study.
Summary · context
Afamelanotide was given to EPP patients as part of standard care.
Report a problemFND-3503484405
02HumanObservational studyEfficacy outcome
EPP patients on afamelanotide treatment had 71.6% more white light exposure during spring than EPP patients off treatment.
In plain wordsIn people with EPP, white light exposure in spring was 71.6% higher on afamelanotide than off treatment.
Peptide
Melanotan I (afamelanotide)
Outcome
IncreaseWhite light exposure in spring, on versus off afamelanotide
Study
n = 26
Comparator
EPP patients off treatment
Outcome group
Photosensitivity and sun tolerance · Skin and wound
Studied dose
Dose not stated
Measurements
increase in light exposure
71.6%
spring, on versus off treatment
Source sentences
Summary
EPP patients on afamelanotide treatment had 71.6% more light exposure during spring compared to EPP patients off treatment (p < 0.01).
2 context sentences(design, population, supporting numbers)
Summary · context
Adult EPP patients visiting the Porphyria Center Rotterdam of the Erasmus MC were included in this single-center longitudinal case-control open-label intervention study.
Summary · context
Afamelanotide was given to EPP patients as part of standard care.
Report a problemFND-3503484402
03HumanObservational studyEfficacy outcome
Afamelanotide treatment in EPP patients resulted in a 6.5% decrease in painful moments in the morning.
In plain wordsIn people with EPP, afamelanotide was linked to 6.5% fewer painful moments in the morning.
Peptide
Melanotan I (afamelanotide)
Outcome
DecreasePainful moments in the morning
Study
n = 26
Comparator
EPP patients off treatment
Outcome group
Pain · Skin and wound
Studied dose
Dose not stated
Measurements
decrease in painful moments
6.5%
morning
Source sentences
Summary
Afamelanotide treatment resulted in a reduction of painful moments in the morning (6.5% decrease) and the evening (8.1% decrease; p < 0.05).
2 context sentences(design, population, supporting numbers)
Summary · context
Adult EPP patients visiting the Porphyria Center Rotterdam of the Erasmus MC were included in this single-center longitudinal case-control open-label intervention study.
Summary · context
Afamelanotide was given to EPP patients as part of standard care.
Report a problemFND-3503484403
04HumanObservational studyEfficacy outcome
Afamelanotide treatment in EPP patients resulted in an 8.1% decrease in painful moments in the evening.
In plain wordsIn people with EPP, afamelanotide was linked to 8.1% fewer painful moments in the evening.
Peptide
Melanotan I (afamelanotide)
Outcome
DecreasePainful moments in the evening
Study
n = 26
Comparator
EPP patients off treatment
Outcome group
Pain · Skin and wound
Studied dose
Dose not stated
Measurements
decrease in painful moments
8.1%
evening
Source sentences
Summary
Afamelanotide treatment resulted in a reduction of painful moments in the morning (6.5% decrease) and the evening (8.1% decrease; p < 0.05).
2 context sentences(design, population, supporting numbers)
Summary · context
Adult EPP patients visiting the Porphyria Center Rotterdam of the Erasmus MC were included in this single-center longitudinal case-control open-label intervention study.
Summary · context
Afamelanotide was given to EPP patients as part of standard care.
Report a problemFND-3503484404

Studies that did not test the peptide alone1

In this study, Melanotan I (afamelanotide) was a lab tool or a carrier, part of a mix, or the subject of a lab method. These results are not evidence about taking Melanotan I (afamelanotide).

05HumanNot a test of Melanotan I (afamelanotide) aloneObservational studyEfficacy outcome
Controls were significantly more exposed to white light than EPP patients off treatment during autumn (95.4%), spring (69.9%) and summer (105.4%).
In plain wordsPeople without EPP had more white light exposure than EPP patients not on treatment. This result does not involve afamelanotide.
Peptide
Melanotan I (afamelanotide)
Outcome
Not applicableWhite light exposure, controls versus EPP patients off treatment
Study
n = 49
Comparator
EPP patients off treatment
Outcome group
Photosensitivity and sun tolerance · Skin and wound
Measurements
higher white light exposure in controls
95.4%
autumn
higher white light exposure in controls
69.9%
spring
higher white light exposure in controls
105.4%
summer
Source sentences
Summary
Controls were statistically significantly more exposed to white light than EPP patients off treatment during autumn (95.4%), spring (69.9%), and summer (105.4%; p = 0.01).
2 context sentences(design, population, supporting numbers)
Summary · context
Adult EPP patients visiting the Porphyria Center Rotterdam of the Erasmus MC were included in this single-center longitudinal case-control open-label intervention study.
Summary · context
Afamelanotide was given to EPP patients as part of standard care.
In this study, Melanotan I (afamelanotide) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking Melanotan I (afamelanotide).
Report a problemFND-3503484401

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

Version 2Current
13 Oct 2026, 21:44 UTC
Study results updated
Version 1
13 Oct 2026, 16:31 UTC
First added · source update from Europe PMC

Subjects

Terms as the source lists them.

Publication types

Journal Article

MeSH terms

Keywords

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