Systemic Treatment Patterns: Highlighting Trends Among Japanese Patients with Psoriasis

Published on: 

In this retrospective review of medical charts, trends in systemic treatment use among psoriasis patients in Japan pointed to several notable findings.

Most plaque psoriasis (PsO) patients initiate treatment with oral drugs as the first option, according to new findings in Japan, and patients begin systemic treatments after a mean period of around 7.8 years after the initial diagnosis.1

These findings and otheers were identified in a recent analysis of medical chart data, with current treatment trends of systemic drugs for Japanese patients with PsO being analyzed to allow for comprehensive guidelines on systemic treatment.

The new chart analysis was authored by Katsuyoshi Habiro, from Tyk2 and Immunology Medical at Bristol Myers Squibb K.K. in Tokyo. Habiro and colleagues noted that while the Japanese Dermatological Association (JDA) has developed guidance related to biologics use and Janus kinase (JAK)-inhibitors for the skin disease, there are no guidelines for systemic treatments of patients with PsO.2,3

“This study aimed to investigate the long-term treatment course, patterns of treatment change for each systemic drug (e.g., drug interruption and switching to other treatments), reasons for treatment change, and the relationship between the reasons for treatment change and subsequent treatment by analyzing the medical records of patients with PsO for at least 2 years,” Habiro and colleagues wrote.


The investigators implemented a retrospective observational study design, and they conducted their research at 4 JDA-certified medical centers found in Japan in the time period between January 2017 - December 31, 2020. They sought to look at data on 120 individuals known to have PsO.

The research team involved tertiary medical institutions which were known to be permitted to dispense biologics to patients with PsO. They also anonymized the data prior to analysis, and the information was collected from electronic medical records of subjects that had begun systemic drugs for the skin disease.

Subjects deemed to be in eligible in the ≥20 years age bracket had to have been diagnosed with PsO at the beginning of their follow-ups, had to have been given specified systemic drugs during the course of the study, and followed for 2 years minimum post-treatment initiation. Those who were excluded from participation were those of certain PsO types at the beginning of follow-up, those already involved in other PsO clinical trials, and those involved in prior use of investigated systemic drugs.

The investigators assessed patient background and demographic information, looking at age, sex, disease duration, and comorbidities at the initiation of patient follow-up meetings. They also gathered systemic drug treatment course information including names of drugs, drug categories, and reasons for alterations.

Data on subjects’ phototherapy (UVB, PUVA) were also examined. The research team also categorized treatment alterations into 6 different types, with interruptions being counted based on schedules for their prescription visits.

The team defined duration of systemic treatment from the beginning to the day preceding the next alteration or the follow-up end. Additionally, Psoriasis Area and Severity Index (PASI) scores were used to determine PsO severity, with the investigators calculating patients’ frequency of treatment changes per 100 patient-years as these alterations were divided by corresponding observation times.


Overall, the research team found 78.1% of those they assessed had begun with oral drugs (56.1% PDE4 inhibitors, 14.0% calcineurin inhibitors, 7.9% vitamin A derivatives). They added, however, that 21.9% of the subjects had begun with biologic treatment (9.6% IL-17 inhibitors, 7.0% tumor necrosis factor inhibitors, 3.5% IL-23 inhibitors, 1.8% IL-12/23 inhibitors).

The team reported that oral drugs were found to have exhibited shorter persistence (e.g., 12-month persistence: vitamin A derivative 35.5%, calcineurin inhibitor 25.8%, PDE4 inhibitor 60.1%). This was distinct from biologics in which IL-23 and IL-17 inhibitors had a persistence rate of 85.6% and 84.7%, respectively.

Throughout the course of the investigators’ research, they found that treatment changes were shown at an incidence of 59.1/100 patient-years, noting that lack of efficacy had been reported as the primary reason for changes specifically among 34.1%. The team’s findings indicate that there may be opportunities for improvement in the appropriate implementation of systemic drugs for PsO in Japan and other regions.

“As more systemic treatment options become available for PsO treatment, using each drug properly will be even more crucial,” they wrote. “We believe that our research has shed light on each existing drug's usage patterns, contributing to the optimization of future psoriasis treatment.”


  1. Tada, Y, Komine, M, Okubo, Y, Habiro, K, Tsuritani, K, Morita, A. Treatment patterns of systemic drug use in Japanese patients with plaque psoriasis: A retrospective chart review. J Dermatol. 2023; 00: 1–13.
  2. Karamata VV, Gandhi AM, Patel PP, Sutaria A, Desai MK. A study of the use of drugs in patients suffering from psoriasis and their impact on quality of life. Indian J Pharm. 2017; 49: 84–88.
  3. Reich K, Korge B, Magnolo N, Manasterski M, Schwichtenberg U, Staubach-Renz P, et al. Quality-of-life outcomes, effectiveness and tolerability of apremilast in patients with plaque psoriasis and routine German dermatology care: results from LAPIS-PSO. Dermatol Ther (Heidelb). 2022; 12: 203–221.