Mogamulizumab-associated rash in people with mycosis fungoides or Sézary syndrome

A Prospective, US-Based Study Assessing Mogamulizumab-Associated Rash in Patients Diagnosed With Mycosis Fungoides or Sézary Syndrome and Treated With Standard of Care Mogamulizumab

Observational City of Hope Medical Center · NCT07003100

See if a rash that appears while taking mogamulizumab is a drug-related rash and how it links to treatment response in adults with relapsed or refractory mycosis fungoides or Sézary syndrome.

Quick facts

Study typeObservational
Enrollment100 (estimated)
Ages18 Years and up
SexAll
SponsorCity of Hope Medical Center Academic / other
Drugs / interventionsmogamulizumab
Locations10 sites (Duarte, California and 9 other locations)
Trial IDNCT07003100 on ClinicalTrials.gov

What this trial studies

This prospective US-based observational study follows adults with relapsed or refractory mycosis fungoides or Sézary syndrome who are newly starting standard-of-care mogamulizumab. Participants complete questionnaires, have serial skin photographs taken, provide blood samples, and undergo skin biopsies when clinically indicated while investigators review medical records. The primary aim is to measure the incidence of mogamulizumab-associated rash (MAR) and analyze whether MAR is associated with overall treatment response. Collected clinical data and biospecimens will also be used to better characterize the rash and explore potential causes.

Who should consider this trial

Good fit: Adults (≥18) with relapsed or refractory mycosis fungoides or Sézary syndrome who are about to start single-agent mogamulizumab and are willing to undergo biopsies, blood draws, photos, and questionnaires.

Not a fit: Patients previously treated with mogamulizumab, those receiving other systemic CTCL therapies, or those unwilling to provide biopsies or blood samples are unlikely to benefit from this study.

Why it matters

Potential benefit: If successful, the study could help clinicians tell drug-related rash apart from disease progression, reducing unnecessary early stopping of mogamulizumab and improving patient management.

How similar studies have performed: Case reports and retrospective series have described mogamulizumab-associated rash and suggested possible links with response, but prospective, multicenter US studies characterizing MAR are limited.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* \* Adult patients (\>= 18 years of age) diagnosed with relapsed/refractory Mycosis Fungoides (MF) stage IB, IIA, IIB, III and IV or Sezary Syndrome(SS), and selected by their treating physician to receive single agent mogamulizumab (newly initiated)

  * Signed informed consent
  * Willing to undergo baseline biopsy and during treatment to evaluate for Mogamulizumab-Associated Rash (MAR) if clinically indicated
  * Willing to provide blood sample at baseline, and if applicable, at onset of Mogamulizumab-Associated Rash (MAR)

Exclusion Criteria:

* \* Other concomitant systemic and skin directed Cutaneous T-cell Lymphoma (CTCL) regimens except for topical steroids

  * Prior treatment with mogamulizumab

Where this trial is running

Duarte, California and 9 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Recurrent Mycosis FungoidesRecurrent Sezary SyndromeRefractory Mycosis FungoidesRefractory Sezary SyndromeStage IB Mycosis Fungoides and Sezary Syndrome AJCC v8Stage IIA Mycosis Fungoides and Sezary Syndrome AJCC v8Stage IIB Mycosis Fungoides and Sezary Syndrome AJCC v8Stage III Mycosis Fungoides and Sezary Syndrome AJCC v8
Last reviewed 2026-06-10 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.