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Study · Observational study · n = 230 · 2024

4 results

The effects of cholecalciferol and afamelanotide on vitamin D levels in erythropoietic protoporphyria: a multicentre cohort study.

Kluijver LG, Nekouei Shahraki M, Wagenmakers MAEM, Hanssen BE, Kuerten V, Schelonke K, Homey B, Langendonk JG

The British journal of dermatology1 Aug 2024Cited by 4 (Europe PMC)

PMID38634774 (opens in a new tab)DOI10.1093/bjd/ljae148 (opens in a new tab)PepBankPUB-38634774
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Summary

BackgroundPatients with erythropoietic protoporphyria experience lifelong painful photosensitivity resulting in a lack of sunlight exposure. Previous studies have shown that 47-63% of patients with EPP suffer from vitamin D deficiency and a high prevalence of osteoporosis. An effective treatment for EPP has been available since 2016: the α-melanocyte stimulating hormone analogue afamelanotide. So far, studies on vitamin D levels in EPP have only investigated patients who have not been treated with afamelanotide.ObjectivesTo investigate the effects of afamelanotide treatment on vitamin D levels in EPP.MethodsA multicentre observational cohort study in adults with EPP from the Erasmus Medical Centre, the Netherlands, and the University Hospital Düsseldorf, Germany, was carried out. Routinely collected vitamin D levels between 2005 and 2021 were used for analysis. Patient exposure to cholecalciferol or afamelanotide was categorized into four treatment groups: untreated, cholecalciferol, afamelanotide and combined treatment. A linear mixed model for longitudinal data was applied to measure the effect of the treatment groups compared with the untreated groups on vitamin D levels.ResultsA total of 230 patients and 1774 vitamin D measurements were included. The prevalence of vitamin D deficiency and severe deficiency remained high despite afamelanotide treatment (< 50 nmol L-1 in 71.8% of patients and < 30 nmol L-1 in 48.1%, respectively). Afamelanotide treatment alone did not lead to a significant average increase in vitamin D levels [β = 0.5, 95% confidence interval (CI) -3.2 to 4.2]. In contrast, cholecalciferol and combined therapy with afamelanotide led to a significant increase in vitamin D levels [β = 11.6 (95% CI 7.2-15.9) and β = 15.2 (95% CI 12.3-18.1), respectively].ConclusionsCholecalciferol remains essential for the treatment of vitamin D deficiency in EPP, irrespective of new treatment options like afamelanotide. Afamelanotide treatment did not affect vitamin D levels. We suggest that future guidelines include continuous monitoring of vitamin D and a prescription for cholecalciferol in all patients with EPP, including those treated with afamelanotide.
CC BYText from Europe PMC. Highlighted sentences are the source of results.

Results from this study4

3 results from studies that gave the peptide. 3 results from people.

  1. 01HumanObservational studyEfficacy outcome

    In adults with erythropoietic protoporphyria, afamelanotide alone did not significantly raise vitamin D levels versus untreated patients.

    In plain wordsIn adults with EPP, afamelanotide alone did not raise vitamin D levels compared with no treatment.

    Peptide
    Melanotan I (afamelanotide)
    Outcome
    No significant changeVitamin D levels
    Study

    n = 230

    Comparator
    Untreated group
    Outcome group
    Hormone levels · Endocrine and hormones
    Studied dose
    Dose not stated

    Measurements

    beta
    0.5 nmol/L
    afamelanotide alone
    95% CI lower
    −3.2 nmol/L
    afamelanotide alone
    95% CI upper
    4.2 nmol/L
    afamelanotide alone

    Source sentences

    Summary
    Afamelanotide treatment alone did not lead to a significant average increase in vitamin D levels [β = 0.5, 95% confidence interval (CI) -3.2 to 4.2].
    2 context sentences
    Summary · context
    A multicentre observational cohort study in adults with EPP from the Erasmus Medical Centre, the Netherlands, and the University Hospital Düsseldorf, Germany, was carried out.
    Summary · context
    A linear mixed model for longitudinal data was applied to measure the effect of the treatment groups compared with the untreated groups on vitamin D levels.
  2. 02HumanObservational studyEfficacy outcome

    In adults with erythropoietic protoporphyria treated with afamelanotide, vitamin D deficiency remained common, below 50 nmol/L in 71.8% of patients.

    In plain wordsIn adults with EPP treated with afamelanotide, most patients still had low vitamin D.

    Peptide
    Melanotan I (afamelanotide)
    Outcome
    Not applicableVitamin D deficiency prevalence (<50 nmol/L) during afamelanotide treatment
    Study

    n: not reported in source

    Outcome group
    Hormone levels · Endocrine and hormones
    Studied dose
    Dose not stated

    Measurements

    Prevalence of vitamin D <50 nmol/L
    71.8%
    afamelanotide-treated patients

    Source sentences

    Summary
    The prevalence of vitamin D deficiency and severe deficiency remained high despite afamelanotide treatment (< 50 nmol L-1 in 71.8% of patients and < 30 nmol L-1 in 48.1%, respectively).
    2 context sentences
    Summary · context
    A multicentre observational cohort study in adults with EPP from the Erasmus Medical Centre, the Netherlands, and the University Hospital Düsseldorf, Germany, was carried out.
    Summary · context
    A linear mixed model for longitudinal data was applied to measure the effect of the treatment groups compared with the untreated groups on vitamin D levels.
  3. 03HumanObservational studyEfficacy outcome

    In adults with erythropoietic protoporphyria treated with afamelanotide, severe vitamin D deficiency remained common, below 30 nmol/L in 48.1% of patients.

    In plain wordsIn adults with EPP treated with afamelanotide, almost half still had severely low vitamin D.

    Peptide
    Melanotan I (afamelanotide)
    Outcome
    Not applicableSevere vitamin D deficiency prevalence (<30 nmol/L) during afamelanotide treatment
    Study

    n: not reported in source

    Outcome group
    Hormone levels · Endocrine and hormones
    Studied dose
    Dose not stated

    Measurements

    Prevalence of vitamin D <30 nmol/L
    48.1%
    afamelanotide-treated patients

    Source sentences

    Summary
    The prevalence of vitamin D deficiency and severe deficiency remained high despite afamelanotide treatment (< 50 nmol L-1 in 71.8% of patients and < 30 nmol L-1 in 48.1%, respectively).
    2 context sentences
    Summary · context
    A multicentre observational cohort study in adults with EPP from the Erasmus Medical Centre, the Netherlands, and the University Hospital Düsseldorf, Germany, was carried out.
    Summary · context
    A linear mixed model for longitudinal data was applied to measure the effect of the treatment groups compared with the untreated groups on vitamin D levels.

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).

  1. 04HumanNot a test of Melanotan I (afamelanotide) aloneObservational studyEfficacy outcome

    In adults with erythropoietic protoporphyria, combined cholecalciferol and afamelanotide therapy significantly raised vitamin D levels versus untreated patients.

    In plain wordsIn adults with EPP, cholecalciferol together with afamelanotide raised vitamin D levels compared with no treatment.

    Peptide
    Melanotan I (afamelanotide)
    Outcome
    IncreaseVitamin D levels
    Study

    n = 230

    Comparator
    Untreated group
    Outcome group
    Hormone levels · Endocrine and hormones

    Measurements

    beta
    15.2 nmol/L
    combined cholecalciferol and afamelanotide
    95% CI lower
    12.3 nmol/L
    combined cholecalciferol and afamelanotide
    95% CI upper
    18.1 nmol/L
    combined cholecalciferol and afamelanotide

    Source sentences

    Summary
    In contrast, cholecalciferol and combined therapy with afamelanotide led to a significant increase in vitamin D levels [β = 11.6 (95% CI 7.2-15.9) and β = 15.2 (95% CI 12.3-18.1), respectively].
    2 context sentences
    Summary · context
    A multicentre observational cohort study in adults with EPP from the Erasmus Medical Centre, the Netherlands, and the University Hospital Düsseldorf, Germany, was carried out.
    Summary · context
    A linear mixed model for longitudinal data was applied to measure the effect of the treatment groups compared with the untreated groups on vitamin D levels.

    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).

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.

  1. Version 2Current

    13 Oct 2026, 21:44 UTC

    Study results updated

  2. Version 1

    13 Oct 2026, 16:31 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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