Patients with relapsed or refractory cutaneous T-cell lymphoma (CTCL) receiving denileukin diftitox-cxdl demonstrated an improvement or maintenance of their overall health-related quality of life (HRQoL), according to findings from Study 302 presented at the European Organisation for Research and Treatment of Cancer Cutaneous Lymphoma Tumour Group (EORTC-CLTG) 2026 Annual Meeting (Abstract 6.2).
“Patients and physicians have told us that both clinical response and quality of life matter in CTCL treatment,” said Leonard Mazur, Chairman and Chief Executive Officer of Citius Oncology. “These data add the patient's voice to the efficacy and durability shown in our pivotal trial.”
Background and Study Methods
The open-label, single-arm, multicenter registrational Study 302 trial explored the efficacy and safety of denileukin diftitox-cxdl in adult patients with relapsed or refractory CTCL of both mycosis fungoides and Sézary syndrome subtypes who were previously treated with at least one prior systemic therapy. Patients received denileukin diftitox-cxdl at 9 mg/kg per day intravenously for 5 days every 21 days for up to 8 cycles.
Findings from the study supported the U.S. Food and Drug Administration approval for denileukin diftitox-cxdl.
Quality-of-life assessments were part of the exploratory endpoints of the study through two patient-reported outcome instruments: Skindex-29 and Functional Assessment of Cancer Therapy—General (FACT-G). Researchers also analyzed the difference among responders vs nonresponders.
Key Findings
Among 69 patients in the primary efficacy analysis set of patients with stage I to III disease, more than 90% completed both assessments at all time points.
Looking at the FACT-G Total Score among responders (n = 25) to denileukin diftitox-cxdl showed that changes from baseline were positive between cycles 2 and 8, with a range of changes from 0.94 to 5.51. On the other hand, nonresponders had changes from baseline of close to 0.
At the end of treatment, the mean change in the FACT-G Total Score was 3.21 for responders and –2.28 for nonresponders.
Analyzing Skindex-29 changes showed a separation of responders from nonresponders for each domain of symptoms, emotions, and functioning. The mean change in the Skindex-29 Total Score for responders declined from –5.38 in cycle 2 to –13.69 for cycle 4, with scores ranging between –8.63 and –12.75 through the end of treatment. For nonresponders, the mean change was near 0 or slightly positive throughout.
Forty-one heavily pretreated patients had a baseline itch score of 20 mm or greater, and 13 of these patients (32%) achieved a clinically meaningful improvement of at least a 20 mm decrease sustained for 4 weeks or more.
“CTCL is a disease of the skin which symptomatic patients must deal with 24/7. Painful, itchy lesions take a real toll on their well-being,” said Myron Czuczman, MD, Chief Medical Officer of Citius Oncology. “In Study 302, patients who responded to denileukin diftitox-cxdl reported sustained quality-of-life improvements, and nearly a third of heavily pretreated patients with significant itch noted its decrease. We believe these findings underscore how important quality-of-life considerations are as practitioners choose between various treatment options for their patients with relapsed or refractory CTCL.”
DISCLOSURES: For full disclosures of the study authors, visit mdpi.com.
