A Study of ESK-001 for the Treatment of Participants With Generalized Pustular Psoriasis or Erythrodermic Psoriasis

Status

Recruiting

Phases

Phase 3

Study type

Interventional

Source

JPRN

Registry ID

JPRN-jRCT2071260031

Enrollment

Registered

2026-05-25

Start date

2026-05-31

Completion date

Unknown

Last updated

2026-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Generalized Pustular Psoriasis or Erythrodermic Psoriasis

Interventions

Participants will receive oral ESK-001 40 mg twice daily for 52 weeks.

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: -The study participant has a diagnosis of generalized pustular psoriasis (GPP) or erythrodermic psoriasis (EP) at screening and Day1. -Candidate for phototherapy or systemic treatment for psoriasis. -Other protocol defined inclusion criteria apply.

Exclusion criteria

Exclusion criteria: -The study participant has a diagnosis of guttate, inverse, drug-induced psoriasis or psoriasis that may affect the evaluation of this clinical trial. However, the study participant who has concomitant psoriatic arthritis may participate in the study. -The study participant has a differential diagnosis of the erythroderma (for example, erythroderma caused by lymphoma or drug eruption) other than EP. -The study participant who doesn't meet the criteria of prior/current concomitant therapy and/or history/conditions of infections. -Any prior exposure to ESK-001, or participation in any study that included a TYK2 inhibitor. -The study female participant who is pregnant, breastfeeding, or may be pregnant, or who wishes to become pregnant after providing informed consent until 90 days after the last dose of the investigational product, or male participant who wishes to father a child. The study female participant of childbearing potential with a positive pregnancy test at screening. -Other protocol defined exclusion criteria apply.

Design outcomes

Primary

Measure	Time frame
Proportion of participants who achieved treatment response based on CGI-I (at Week 16)	—

Secondary

Measure	Time frame
At each assessment time point, the following endpoints will be evaluated: -Proportion of participants achieving treatment response based on CGI-I -PASI 75 response rate -PASI 90 response rate -sPGA 0/1 response rate -BSA -DLQI 0/1 response rate -Change from baseline in JDASI score -Severity assessment based on JDASI score -GPPGA 0/1 response rate -GPPASI 75 response rate -Other secondary endpoints defined in the clinical study protocol	—

Measure

Time frame

At each assessment time point, the following endpoints will be evaluated: -Proportion of participants achieving treatment response based on CGI-I -PASI 75 response rate -PASI 90 response rate -sPGA 0/1 response rate -BSA -DLQI 0/1 response rate -Change from baseline in JDASI score -Severity assessment based on JDASI score -GPPGA 0/1 response rate -GPPASI 75 response rate -Other secondary endpoints defined in the clinical study protocol

—

Contacts

Public ContactContact for Clinical Trial

Kaken Pharmaceutical Co. Ltd.

kaken-jrct@e-medinfo.com+81-120-391-004

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Jul 3, 2026