Assessment of flare frequency and severity of generalized pustular psoriasis in Japanese patients: A retrospective chart review study

Akimichi Morita, Yukari Okubo, Shinichi Imafuku, Yayoi Tada, Keiichi Yamanaka, Kazumitsu Sugiura, Yukie Yamaguchi, Masahito Yasuda, Hitoshi Tsuchihashi, Morihisa Saitoh, Wataru Sakamoto, Ryuhei Okuyama

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)


Background: Generalized pustular psoriasis (GPP) is a rare and often refractory disease, and GPP flares can be life threatening. The rarity of GPP prevents the development and evaluation of effective GPP-specific treatments and obstructs disease understanding. Objectives: To evaluate the frequency and severity of GPP flares and the clinical background and treatment history of patients with GPP in Japan. Methods: This retrospective, longitudinal, Japanese chart review study included patients diagnosed with GPP (according to Japanese Dermatological Association [JDA] diagnostic criteria), with ≥6 months of continuous observation within 10 years of protocol approval at study sites. Primary outcomes: the frequency and severity of GPP flares during follow-up. Secondary outcomes: patient characteristics (at time of initial GPP diagnosis) and GPP treatment during follow-up. Results: Overall, 205 Japanese patients were included; 106/205 (51.7%) were male, 146/205 (71.2%) were aged <65 years. Few patients had a family history of GPP (7/155, 4.5%) or psoriasis-related diseases (6/120, 5.0%). At baseline, 36.1% (74/205), 30.7% (63/205) and 33.2% (68/205) of patients had mild, moderate and severe GPP, respectively; GPP flares were reported by 177/205 patients (86.3%), which were mostly moderate in severity (52/205; 25.4%) or severe (99/205; 48.3%). During follow-up, GPP flares were reported by 70/205 patients (34.1%): 47/205 (22.9%) had 1 flare and 23/205 (11.2%) had ≥2. Among the 106 flare events reported during follow-up, 1 was mild, 55 were moderate and 50 were severe. The median time to first GPP flare was 7.7 years and the overall incidence of GPP flares during follow-up was 11.5/100 person-years. During follow-up, topical treatment (195/205; 95.1%), systemic therapy other than corticosteroids (177/205; 86.3%) and biologics (163/205; 79.5%) were most frequently used. Conclusions: During follow-up, over one-third of Japanese patients with GPP experienced mostly moderate-to-severe GPP flares, despite available treatments. There remains an unmet need for effective GPP treatment options.

Original languageEnglish
Pages (from-to)261-272
Number of pages12
JournalJEADV Clinical Practice
Issue number2
Publication statusPublished - 06-2023

All Science Journal Classification (ASJC) codes

  • Dermatology


Dive into the research topics of 'Assessment of flare frequency and severity of generalized pustular psoriasis in Japanese patients: A retrospective chart review study'. Together they form a unique fingerprint.

Cite this