A new study suggests that melanin – the pigment responsible for the color of skin, hair and eyes – may have an unexpected effect on drug absorption.
According to a study in October, in Human Genomicsa melanin can absorb certain medications (administered both topically and orally). This has an impact on the distribution of the necessary dose to the tissues that need treatment.
As such, this phenomenon can lead to variations in patients’ responses to standard doses of medication depending on their skin tone.
Previous investigations, cited in this study, already theorized this hypothesis.
For example, nicotine binds to melanin, influencing people’s smoking habits depending on their pigmentation. There is also evidence that toxic chemicals, such as those found in fertilizers and pesticides, can accumulate in higher concentrations in darker skin.
This differentiation suggests that safe exposure levels may vary between individuals of different ethnicities – a hitherto ignored aspect in pre-clinical research and clinical trials of new medicines.
To resolve these discrepancies, Sophie Zaaijer and Simon Groenresearchers at the University of California, now propose the use of more diverse cellular models.
Recent advances in cell biology already allow the creation of cellular models 3D that accurately imitate the different tones of human skin. These models are essential for testing the interaction of drugs with melanin in the pre-clinical phases, thus increasing the precision of studies.
As noted by , another innovation mentioned in the study are the models “organ on a chip”which simulate various human cells and organs in a compact device.
These devices could be particularly useful for studying how drugs simultaneously interact with melanin in the skin and enzymes in the liver, providing valuable information for clinical trials.
The lack of diversity in clinical trials is a concern highlighted by the study authors, with geographic and financial obstacles that prevent the participation of minority groups.
This debate highlights the need for greater representation in clinical and preclinical studies, especially in terms of skin pigmentation, a variable that can significantly influence the effectiveness of medications.
The inclusion of this variable could lead to more accurate and safer innovationsbenefiting the entire society.
“Representation in clinical trials is a critical issue for the clinical trials community,” he commented to Live Science, Jakub Hlávkafrom the University of Southern California, who was not involved in the study.
“Fortunately, representation and diversity in clinical research has improved over time,” he added.
In a , Hlávka concluded that lack of representation in clinical trials compromises the generalizability of trial results to the entire US population.
“Further analysis could include studying the representation of populations with different skin tones in clinical trials, particularly in areas where there may be implications for the clinical effectiveness of investigational drugs,” concluded the expert.
