Patient Reported Outcomes With UVA-1 Therapy for Treatment of Sclerosing Skin Diseases

Ultraviolet (UV) therapy has been used in dermatology for decades. UVA-1 phototherapy uses the longest wavelengths in the UV spectrum from 340-400 nm. It can penetrate the skin deeper than other types of phototherapy and target different cell types including fibroblasts. In sclerosing skin conditions UVA-1 appears to be superior to other forms of UV therapy. Medium-to-high dose UVA-1 also appears to be superior to low dose UVA-1 for sclerosing conditions.

Sclerosing skin diseases treated with UVA-1 include systemic sclerosis (SSc), morphea and sclerodermatous graft vs. host disease (GVHD). These are immune-mediated conditions that lead to skin fibrosis and may be associated with significant morbidity. These conditions share some common features including fibrotic skin changes that may have an active inflammatory stage followed by induration and scarring. Due to the depth of skin involvement, clinical assessment of the degree of active inflammation and depth of involvement is often challenging.

SSc, also called scleroderma, is a rare chronic autoimmune disease that can have a wide range of cutaneous, joint, and internal organ involvement. In the skin, SSc is characterized by enhanced fibroblast activity leading to hypertrophic dermal collagen that results in thickened, less flexible skin. SSc is often divided into two types based on extent of skin involvement: diffuse SSc and limited SSc. Morphea has similar cutaneous changes to SSc but lacks the internal organ involvement. Some of the common subtypes of morphea include circumscribed, linear, and generalized. Sclerodermatous GVHD, a complication of allogenic bone marrow or peripheral blood stem cell transplants, results in fibrotic skin changes that can be widespread and cause morbidity.

Multiple studies report skin improvement in these conditions using UVA-1. This improvement likely involves both dampening inflammation and reducing fibrosis. However, these studies generally lack validated clinical outcome measures. Development of these outcome measures has been slowed by the lack of tools to adequately assess change. Physician assessment, clinical scores, medical imaging, and tools such as a durometer have all been used to attempt to objectively measure changes with therapy over time, but all have limitations.

Patient reported outcomes (PROs) have attracted significant attention in clinical research in the past decade and are required by the FDA for clinical trials. These instruments refer to health outcomes reported directly by the patient who experienced the intervention. Established and validated PRO measures exist and have been used to evaluate multiple medical treatments. While patients have verbally reported improvement of their sclerosing skin disease with UVA-1, PROs have not been rigorously studied. In sclerosing skin diseases where clinical change is difficult to measure, PROs may offer a better way to study the impact of treatments like UVA-1.