Porphyria refers to a group of rare disorders that cause issues with the production of heme, which is part of what makes up hemoglobin (a protein in your red blood cells that helps bring oxygen to tissues). As porphyrin (a precursor to heme) builds up in the body, it can cause a number of nervous system and skin issues. For example, people with the rare diseases erythropoietic protoporphyria (EPP) and X-linked protoporphyria (XLP) have too many protoporphyrins. This causes photosensitivity, or extreme sensitivity to light. Sun exposure can cause debilitating and extreme pain and inflammation.

There is a treatment for adults with EPP or XLP called Scenesse; implanted every two months, Scenesse heightens skin pigmentation. However, XLP and EPP often appear in childhood. This leaves children and adolescents with little assistance or treatment. While they can use zinc oxide sunscreen, cover up in sun-protective clothing, or stay indoors, EPP and XLP can be incredibly isolating for children. 

Identifying a Treatment for these Rare Diseases 

But, shares Medical XPress, an experimental treatment called dersimelagon could change the treatment landscape and increase access to care. The National Cancer Institute explains that dersimelagon is:

an orally bioavailable selective, non-peptide melanocortin-1 receptor agonist that can potentially be used to prevent phototoxicity. Upon administration, dersimelagon targets, binds to, and activates MC1R…[which] is involved in regulating skin and hair color.

So dersimelagon works—similarly to Scenesse—by increasing skin pigmentation. Doctors believe that dersimelagon can overcome current treatment barriers by:

• Allowing for an adjustable dose approach, making it easier to administer to treatment
• Being taken orally, reducing the need to visit doctors for an implant or having to travel to a doctor that provides these implants 
• Providing an additional treatment option for patients who might experience negative side effects on Scenesse

A Phase 2 study of dersimelagon for these rare diseases, the results of which were published in the New England Journal of Medicine, compared the treatment to a placebo. 102 adults with EPP or XLP enrolled. Findings from the study show that:

• Dersimelagon allowed people with EPP or XLP to stay in the sun for 1 hour longer each day. Normally, sun exposure causes symptoms within 10-30 minutes; these individuals were able to stay out for 70-100 minutes without an issue. 
• This treatment was safe and relatively well-tolerated. Some adverse reactions did occur, but these tended to be mild in nature. Adverse reactions included headaches, freckling, and nausea. 

More research is undoubtedly needed moving forward. However, if effective, this treatment could significantly improve happiness and quality-of-life for people with these rare diseases.