PracticalDermatology

Shawn Kwatra, MD, has devoted much of his career to advancing the understanding of itch and addressing minority representation in dermatology. He is currently the director of the Johns Hopkins Itch Center and an associate professor of dermatology at the Johns Hopkins University School of Medicine in Baltimore and will be transitioning to the University of Maryland, where he will serve as chair of dermatology and chief of service of dermatology at the University of Maryland Medical Center starting in 2024. Dr. Kwatra also serves on the Board of Directors of the Skin of Color Society and is currently the National Secretary/Treasury of the Society.

He sat down with Practical Dermatology® magazine to discuss what’s new in itch and ethnic skin.

What are the biggest unmet needs in people with darker skin types?

Dr. Kwatra: There are many conditions that have clinically significant racial differences in presentation and limited available therapeutics. In particular, patients with skin of color have few options for diseases that have significant pigment disturbances as well as fibrotic diseases such as keloids. We still do not know how well medications work in skin of color patients with inflammatory skin diseases such as atopic dermatitis and prurigo nodularis because many clinical trials have had so few minority patients.

Tell us about your work with the Skin of Color Society and how it has improved these issues.

Dr. Kwatra: We are focused on growing the influence and impact of the Skin of Color Society globally in all facets of dermatology. We have a number of mentoring programs and are also leading efforts to increase diversity in clinical trials.

You are involved in YoungMD Connect (YMDC) as a mentor. Why is this so important is it to you?

Dr. Kwatra: Mentoring the next generation of leaders is very important to the continued growth of our specialty. Our trainees and young dermatologists are going to be tomorrow’s innovators, so it is important to me to develop our emerging leaders to move our specialty forward.

Are we getting better at teaching doctors how to identify cutaneous diseases across skin types?

Dr. Kwatra: In the last few years, there has been a great effort in dermatology to increase the number of photos from diverse patient populations. We need to work on making these resources accessible to trainees. Most clinical trials for new therapeutics still do not have sufficient diversity. This is an important area we can do better in.

Tell us about your recent prurigo nodularis research.

Dr. Kwatra: I am very excited to share our recent publication in the New England Journal of Medicine on a phase 3 trial of nemolizumab for the treatment of prurigo nodularis, an incredibly pruritic disease that disproportionately affects African American and Asian patients.1 Nemolizumab works rapidly to reduce itch and is given as an injection every four weeks, so we are very excited with its development and that it can very rapidly reduce itch, improve sleep, and improve skin lesions.

We are also making big strides in understanding racial differences in the biology of prurigo nodularis, and our recent study was the first genetic study performed in prurigo nodularis patients.2 For this study, we developed a polygenic risk score that predicts a diagnosis of prurigo nodularis in two independent and continentally distinct populations. We also performed a genome-wide association study, which uncovered genetic variants associated with prurigo nodularis, including one near PLCB4 and others near TXNRD1. We also discovered that Black patients have greater than two times the genetic risk of developing prurigo nodularis and that combining the polygenic risk score and self-reported race was significantly predictive of prurigo nodularis. The findings suggest that genetics, environmental influence, and social determinants of health likely affect the development of prurigo nodularis and may contribute to clinically observed racial disparities.

Our group is also National Institutes of Health (NIH)-funded for studying racial differences in atopic dermatitis, and we are working to molecularly characterize the heterogeneity in disease in a large cohort of skin of color patients.

1. Kwatra SG, Yosipovitch G, Legat FJ,et al. OLYMPIA 2 Investigators. Phase 3 trial of nemolizumab in patients with prurigo nodularis. N Engl J Med. 2023 Oct 26;389(17):1579-1589. doi: 10.1056/NEJMoa2301333. PMID: 37888917.

2. Vasavda C, Wan G, Szeto MD, et al. A polygenic risk score for predicting racial and genetic susceptibility to prurigo nodularis. Epub ahead of print. J Invest Dermatol. 2023 May 26:S0022-202X(23)02125-5. doi: 10.1016/j.jid.2023.04.033. PMID: 37245863.