Psoriasis therapies, specifically biologics, have significantly increased the number of patients who achieve clear skin. Despite these improvements, some patients are contraindicated, do not wish to start systemic medications, or have not yet achieved clear skin despite systemic treatment. In these and other instances, phototherapy remains a viable option.
“Phototherapy is a highly effective and safe treatment option for psoriasis,” said Joel Gelfand, MD, MSCE, professor of dermatology and epidemiology, vice chair of clinical research, and director of the Psoriasis and Phototherapy Treatment Center at the University of Pennsylvania Perelman School of Medicine in Philadelphia. He noted recent research from a randomized controlled trial demonstrated similar benefits to treatment with narrowband phototherapy compared with adalimumab (Humira) on improvements in Psoriasis Area and Severity Index score and patient-reported outcomes in patients with moderate to severe psoriasis.1 Narrowband UV-B (NB-UVB) phototherapy also improved some markers of systemic inflammation known to be related to cardiovascular disease and improved high-density cholesterol (the “good” cholesterol) compared with placebo.2
“It also has an important role to play in some of our most challenging cases, such as psoriasis affecting the palms and soles, psoriasis localized to the scalp, or as combination treatment in patients not responding ideally to systemic treatment,” he added.
Recently, the American Academy of Dermatology (AAD) and National Psoriasis Foundation (NPF) released updated guidelines on the use of phototherapy for the treatment of psoriasis.3 “It is a master class in the uses of phototherapy in patients with psoriasis,” Dr Gelfand said, who was a member of the working group that developed the guidelines.
“One of the biggest challenges for creating the guidelines was incorporating all of our knowledge and data about the various forms of phototherapy and their role in different subtypes of psoriasis,” he said. NB-UVB is recommended for generalized plaque psoriasis in adult patients and guttate psoriasis in patients of all ages. To increase the efficacy of treatment, the guidelines recommend combining NB-UVB with vitamin D analogues, retinoids, and corticosteroids, as well as apremilast (Otezla) for patients with inadequate response to NB-UVB monotherapy. Targeted UV-B therapy is recommended in the guidelines for patients with localized plaque psoriasis and individualized lesions among those with extensive disease. The guidelines also recommend excimer laser for scalp psoriasis. Dosing of light therapy is based on skin phototype or minimal erythema dose (Table).
The guidelines3 recommend NB-UVB over psoralen UV-A (PUVA) monotherapy because it is considered safer and more convenient for patients. However, topical PUVA phototherapy is considered superior to localized NB-UVB therapy for localized plaque psoriasis, including palmoplantar and palmoplantar pustular psoriasis. Broadband UV-B (BB-UVB) monotherapy is considered inferior to NB-UVB, oral PUVA, and topical PUVA monotherapy, but it can be offered to adults with generalized plaque psoriasis if NB-UVB is unavailable. According to the guidelines, excimer laser is considered more effective than an excimer light, which is more effective than localized NB-UVB, for localized plaque psoriasis.
While the working group found insufficient evidence for the use of Grenz ray and visible light therapy for the treatment of psoriasis, they noted that pulsed dye laser showed promise for the treatment of nail psoriasis in clinical studies.3
According to Dr Gelfand, patients who are motivated, follow instructions, and adhere to treatment recommendations are good candidates for phototherapy. Patients who are not responding ideally to systemic or biologic therapy can undergo phototherapy as well, including those with well-controlled psoriatic arthritis with active skin involvement, he said. Add-on therapies, such as acitretin (Soriatane), can help improve the efficacy of phototherapy among patients who are not achieving an ideal response. However, “patients with psoriasis affecting the genital area are generally not great candidates for phototherapy as the genitals need to be protected from UV light,” said Dr Gelfand.
The guidelines3 stress the importance of patient preference when selecting a phototherapy option. In addition, the guidelines discuss access issues for certain treatments. PUVA, in particular, has many limitations. Only one oral PUVA is approved in the United States (methoxsalen), and fewer centers offer topical PUVA options due to wider use of targeted UV-B therapy. Likewise, bath PUVA requires maintenance of a bath unit and can be hard for providers to get reimbursed, plus one therapy (trimethylpsoralen) is not approved in the United States despite efficacy and wide use in Europe.
Home-based Phototherapy and Areas of Future Research
The guidelines3 recommend home-based NB-UVB phototherapy, especially for patients where access to in-office NB-UVB phototherapy is limited. According to Dr Gelfand, the strength of this recommendation was level B due to limited data in the United States. “There is therapeutic uncertainty because of the limited data, which results in some clinicians not feeling comfortable prescribing home-based phototherapy,” he said. Many patients also encounter barriers in accessing coverage of these devices from their insurance company, he added.
To help provide more data for home-based NB-UVB phototherapy, Dr Gelfand and his team are conducting a pragmatic trial of 1050 patients with plaque or guttate psoriasis to compare the effectiveness of home-based vs office-based phototherapy, which is funded by the Patient Centered Outcomes Research Institute. “The goal of this research is to address knowledge gaps and ultimately help make the delivery of phototherapy more patient centered,” he said. To learn more about the LITE Study, please visit www.thelitestudy.com.
The AAD and NPF released three guidelines earlier this year on the management of psoriasis with biologics,4 the management of comorbidities in patients with psoriasis,5 and the treatment of pediatric patients.6 Development of guidelines for nonbiologic systemic therapy and topical therapy are underway.
1. Noe MH, Wan MT, Shin DB, et al. Patient-reported outcomes of adalimumab, phototherapy, and placebo in the Vascular Inflammation in Psoriasis Trial: a randomized controlled study. J Am Acad Dermatol. 2019;81(4):923-930. doi:10.1016/j.jaad.2019.05.080
2. Mehta NN, Shin DB, Joshi AA, et al. Effect of 2 psoriasis treatments on vascular inflammation and novel inflammatory cardiovascular biomarkers: a randomized placebo-controlled trial. Circ Cardiovasc Imaging. 2018;11(6):e007394. doi:10.1161/CIRCIMAGING.117.007394
3. Elmets CA, Lim HW, Stoff B, et al. Joint American Academy of Dermatology-
National Psoriasis Foundation guidelines of care for the management and treatment of psoriasis with phototherapy. J Am Acad Dermatol. 2019;81(3):775-804. doi:10.1016/j.jaad.2019.04.042
4. Menter A, Strober BE, Kaplan DH, et al. Joint AAD-NPF guidelines of care for the management and treatment of psoriasis with biologics. J Am Acad Dematol. 2019;80(4):1029-1072. doi:10.1016/j.jaad.2018.11.057
5. Elmets CA, Leonardi CL, Davis DMR, et al. Joint AAD-NPF guidelines of care for the management and treatment of psoriasis with awareness and attention to comorbidities. J Am Acad Dermatol. 2019;80(4):1073-1113. doi:10.1016/j.jaad.2018.11.058
6. Menter A, Cordoro KM, Davis DMR, et al. Joint American Academy of Dermatology–National Psoriasis Foundation guidelines of care for the management and treatment of psoriasis in pediatric patients [published online November 5, 2019]. J Am Acad Dermatol. doi:10.1016/j.jaad.2019.08.049