Scenesse may help reduce liver damage in EPP patients
The med is used primarily to ease photosensitivity in people with erythropoietic protoporphyria
Treatment with the implantable medication Scenesse (afamelanotide), which is approved to help reduce light intolerance in people with erythropoietic protoporphyria (EPP), also may help to reduce liver damage associated with the disease.
That finding, in the study “Afamelanotide Is Associated with Dose-Dependent Protective Effect from Liver Damage Related to Erythropoietic Protoporphyria,” was published in the journal Life.
EPP is caused by mutations that lead to the toxic buildup of a molecule called protoporphyrin (PPIX) in the body. The hallmark symptom of the disease is photosensitivity, where sunlight causes skin reactions like pain and redness.
Liver damage also is a common problem in EPP. Up to one in five patients have abnormalities on liver function tests, and failure of that organ is fatal to about 4% of people with EPP. There aren’t currently any established treatments for liver disease in EPP.
Scenesse is a therapy that’s implanted under the skin, where it releases a compound that acts as an antioxidant and helps stimulate the production of melanin — the brownish pigment that helps protect the skin from light-based damage. Scenesse is approved in the U.S. and Europe to help manage photosensitivity in people with EPP, and studies suggest it can help improve patients’ life quality and make activities easier.
Here, a team of researchers in Switzerland analyzed laboratory data from 70 EPP patients treated at their center, aiming to see how Scenesse affects liver function tests.
Under current approvals, Scenesse implants can be given once every 60 days, with patients being able to receive a maximum of six to seven implants per year. Authorities in Europe, but not the U.S., recommend that patients be limited to only four implants per year. The researchers noted, however, that at their clinic “many patients required 5-6 doses per year, as they were symptomatic throughout the year.”
Significance of PPIX levels
Laboratory data showed that PPIX levels tended to correlate with blood tests used to measure enzymes for liver function. In other words, patients with higher PPIX levels also tended to have more signs of liver damage. According to researchers, this finding indicates that “PPIX concentration is a predictor of EPP-related liver damage.”
Using statistical analyses, researchers found that liver function tests tended to improve in patients who had received more doses of Scenesse in the previous year. Additionally, liver function tests were generally worse the longer it had been since the patients’ last therapy implant.
Data also suggested that PPIX levels tended to decrease with Scenesse treatment.
Researchers noted that the overall number of Scenesse implants had a much stronger effect on liver function tests than it did on PPIX levels, whereas the time since the last implant had a stronger effect on PPIX levels than on liver function.
Collectively, these data suggest that Scenesse could have protective effects on the liver of EPP patients, which are likely independent of its protective effects against light-related damage.
“The variable time course, a more short-term effect on PPIX concentrations, and a more long-term effect on [liver function tests] support the concept of two independent, beneficial effects of [Scenesse],” the researchers wrote.
In looking at the data, researchers noted that the most profound effects on liver function tests were seen among patients who received five or six implants per year. In patients whose liver function tests indicated the presence of liver damage, beneficial effects were seen only for those who received at least nine implants over the course of two years.
“With respect to the protection of liver function, the three to four doses per year, as imposed as a yearly maximum by the EMA, seem to be insufficient, and at least 9 implants during the previous two years are required,” the researchers wrote. “We, therefore, speculate that a shorter time interval of implant applications, such as every four to six weeks, could lead to pronounced positive effects on EPP-related liver damage, for which, currently, there is no effective treatment.”
More research needed
While they noted a need for more research to validate these findings, the team said that more frequent Scenesse implants might be considered especially for EPP patients at high risk of liver problems.
This study was funded by the foundation for scientific research at Stadtspital Zürich. Clinuvel Pharmaceuticals, the company that sells Scenesse, was not directly involved, though some of the co-authors disclosed having previously received financial support from the company.