• Advanced analytical methods integrating clinical trial and real-world data address key evidence gaps in rare, difficult-to-treat blood cancers 
• Across both studies, mogamulizumab was associated with improved survival outcomes compared to standard of care
   

PRINCETON, N.J., June 30, 2026 (GLOBE NEWSWIRE) -- Researchers at the World Congress of Cutaneous Lymphoma 2026 presented two indirect treatment comparison (ITC) analyses examining the impact of mogamulizumab on long-term outcomes, including overall survival (OS), in patients with relapsed or refractory mycosis fungoides (MF) or Sézary syndrome (SS), two subtypes of cutaneous T-cell lymphoma (CTCL). These findings, which drew on clinical trial and real-world data, expand the growing body of evidence supporting mogamulizumab use and address critical information gaps where comparative survival data have been limited. The research was funded by Kyowa Kirin Co. Ltd (TSE: 4151).

“Indirect treatment comparisons help to bridge critical evidence gaps in MF and SS, giving clinicians a clearer picture of long-term outcomes in real-world practice,” said Professor H. Miles Prince, Principal Investigator, Peter MacCallum Cancer Centre in Melbourne, Australia. “This deeper understanding enables us to make informed treatment decisions and ultimately provide more personalized, effective care for our patients.”

MF and SS are rare, progressive forms of CTCL associated with substantial morbidity in advanced stages and often require multiple lines of treatment. In the phase 3 MAVORIC trial, mogamulizumab improved progression-free survival versus vorinostat in adult patients with relapsed or refractory MF or SS, but a high rate of treatment crossover limited direct assessment of overall survival.

To address this limitation, two independent studies used MAVORIC and real-world data to estimate comparative OS using ITC methods while accounting for patient differences across treatment groups and data sources. These findings aim to help address evidence gaps that limit access in some countries and support informed treatment decision-making.

“In rare diseases like CTCL, clinical trials are often not designed to evaluate long-term treatment outcomes like overall survival,” said Dr. Angela Williams, PhD, Global Head Health Economics and Outcomes Research at Kyowa Kirin. “By applying advanced analytical approaches, we can integrate clinical trial and real-world data to better assess the long-term impact of a treatment like mogamulizumab on overall survival and other outcomes. This approach reflects our continued commitment to advancing research that informs treatment decisions in rare, hard-to-treat hematologic malignancies like CTCL, helping to improve the lives of patients and their care partners.”

ITC Methodology and Results

In two separate ITC studies, researchers analyzed survival outcomes in cohorts of patients with relapsed or refractory MF or SS by comparing patient-level data from the mogamulizumab arm of the MAVORIC trial (n=186) with real-world registry data from Australia and Denmark. Vorinostat, the active comparator in MAVORIC, is part of the standard of care in Australia but unavailable in Denmark. Key limitations of these analyses include the retrospective nature of the studies and potential differences in advances and standards of care over time.

Australia (Campbell BA, et al): Real-world data from the Australian Peter MacCallum Cancer Centre Cutaneous Lymphoma database included 67 patients treated with vorinostat between January 2005 and November 2024. After adjusting for baseline differences:

• Median OS was not reached for patients receiving mogamulizumab, compared with 31.0 months for patients receiving vorinostat.
• Mogamulizumab was associated with a significantly lower risk of death compared with vorinostat (hazard ratio [95% confidence interval]: 0.48 [0.30, 0.76]; p=0.002).
• Median time to next treatment (TTNT) was numerically longer with mogamulizumab versus vorinostat (9.13 months vs. 5.82 months; hazard ratio [95% confidence interval]: 0.76 [0.52, 1.11]; p=0.20), though this difference was not statistically significant.
   

Denmark (Morgante N, et al): Real-world data from Danish national registries included 209 patients receiving standard of care treatment between January 1996 and April 2024. After statistical weighting: 

• Patients receiving mogamulizumab did not reach median OS, compared with 17.0 months for patients receiving standard of care.
• Mogamulizumab was associated with a significantly lower risk of death versus standard of care (hazard ratio [95% confidence interval]: 0.38 [0.25, 0.59]; p<0.001).

U.S. POTELIGEO (mogamulizumab-kpkc) Indication

POTELIGEO injection for intravenous infusion is indicated for the treatment of adult patients with relapsed or refractory mycosis fungoides (MF) or Sézary syndrome (SS) after at least one prior systemic therapy.

Important Safety Information

WARNINGS AND PRECAUTIONS

Dermatologic toxicity: Monitor patients for rash throughout the course of treatment. For patients who experienced dermatologic toxicity in Trial 1, the median time to onset was 15 weeks, with 25% of cases occurring after 31 weeks. Interrupt POTELIGEO for moderate or severe rash (Grades 2 or 3). Permanently discontinue POTELIGEO for life-threatening (Grade 4) rash or for any Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN).

Infusion reactions: Most infusion reactions occur during or shortly after the first infusion. Infusion reactions can also occur with subsequent infusions. Monitor patients closely for signs and symptoms of infusion reactions and interrupt the infusion for any grade reaction and treat promptly. Permanently discontinue POTELIGEO for any life-threatening (Grade 4) infusion reaction.

Infections: Monitor patients for signs and symptoms of infection and treat promptly.

Autoimmune complications: Interrupt or permanently discontinue POTELIGEO as appropriate for suspected immune-mediated adverse reactions. Consider the benefit/risk of POTELIGEO in patients with a history of autoimmune disease.

Complications of allogeneic HSCT after POTELIGEO: Increased risks of transplant complications have been reported in patients who received allogeneic HSCT after POTELIGEO. Follow patients closely for early evidence of transplant-related complications.

ADVERSE REACTIONS

The most common adverse reactions (reported in ≥10% of patients) with POTELIGEO in the clinical trial were rash, including drug eruption (35%), infusion reaction (33%), fatigue (31%), diarrhea (28%), drug eruption (24%), upper respiratory tract infection (22%), musculoskeletal pain (22%), skin infection (19%), pyrexia (17%), edema (16%), nausea (16%), headache (14%), thrombocytopenia (14%), constipation (13%), anemia (12%), mucositis (12%), cough (11%), and hypertension (10%).

You are encouraged to report suspected adverse reactions to Kyowa Kirin, Inc. at 1-844-768-3544 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Please see additional Important Safety Information in full Prescribing Information as well as Patient Information.

About Kyowa Kirin

Kyowa Kirin aims to discover and deliver novel medicines and treatments with life-changing value. As a Japan-based Global Specialty Pharmaceutical Company, we have invested in drug discovery and biotechnology innovation for more than 70 years and are currently working to engineer the next generation of antibodies and cell and gene therapies with the potential to help patients with high unmet medical needs, such as bone & mineral, intractable hematological diseases/hemato-oncology, and rare diseases. A shared commitment to our values, to sustainable growth, and to making people smile unites us across the globe.  You can learn more about the business of Kyowa Kirin at www.kyowakirin.com.

COR-US-POT-0016 June 2026

CONTACT:

Susan Thiele
Head of Therapeutic Communications, North America

susan.thiele.38@kyowakirin.com