Lymphir Launches in US as First New Systemic for CTCL in Over 7 Years

Citius Oncology recently announced the launch of Lymphir (denileukindiftitox-cxdl) in the US as a new systemic option for adults with relapsed or refractory stage I–III cutaneous T-cell lymphoma (CTCL) after at least one prior systemic therapy. Lymphir, now commercially available through specialty distributors, is the first FDA-approved systemic treatment for CTCL in more than 7 years and carries a permanent J-code (J9161) effective April 1, 2025. Lymphir also holds a Category 2A recommendation in the NCCN Guidelines for CTCL.¹

Lymphir is a recombinant IL-2 receptor–directed fusion protein that delivers diphtheria toxin fragments intracellularly after IL-2R binding, leading to protein synthesis inhibition and cell death. The therapy also depletes immunosuppressive T-regulatory cells, supporting antitumor activity.¹

CTCL presents primarily with skin involvement, most often as patches, plaques, or tumors driven by malignant T-cells. These lesions are frequently accompanied by severe pain and pruritus, contributing significantly to impaired quality of life. CTCL is the most common form of cutaneous non-Hodgkin lymphoma and encompasses several subtypes, with mycosis fungoides and Sézary syndrome representing the majority of cases.¹

At the recent 2025 Inflammatory Skin Disease Summit in New York, Patrick Brunner, MD, a dermatologist at the Kimberly and Eric J. Waldman Melanoma and Skin Cancer Center and associate professor of dermatology and Director of the Cutaneous Lymphoma Clinic at Mount Sinai in New York, discussed how studying CTCLs, particularly mycosis fungoides, can deepen clinicians’ understanding of chronic inflammatory dermatoses such as atopic dermatitis. Brunner started with a challenge: clinicians who treat large volumes of atopic dermatitis and psoriasis should remain vigilant for early CTCL, because clinical and histologic mimicry remains a major diagnostic barrier. As he noted, “mycosis fungoides can, at times, be difficult to differentiate both clinically and histopathologically from either psoriasis or atopic dermatitis or eczema in general.”²

The FDA approval of Lymphir was supported by Study 302, which enrolled patients with previously treated stage I–III CTCL. The objective response rate reached 36.2%, and 84% of evaluable patients demonstrated skin tumor burden reduction. Notably for dermatology clinicians, activity extended to severe pruritus, a major driver of quality-of-life impairment. Importantly, treatment was not associated with cumulative toxicity.¹

“Lymphir is an important new treatment option for the CTCL community, and its launch marks the beginning of a new chapter for Citius Oncology,” said Leonard Mazur, Chairman and CEO of Citius Oncology and Citius Pharmaceuticals, in the news release. He noted the phase 3 median time to response of 1.4 months, adding, “Lymphir addresses a clear clinical need in a disease with limited treatment options.” He emphasized expectations for meaningful clinical uptake and a US market valued at more than $400 million.¹

Clinicians can access prescribing information, reimbursement resources, ordering guidance, and patient support tools—including the Citius Advantage assistance program—at www.lymphirhcp.com. International expansion is underway through a new distribution partnership with Integris Pharma S.A. to initiate named-patient access programs across parts of Southern Europe and the Balkans.¹

For clinicians managing chronic, relapsing CTCL, Lymphir’s rapid responses, pruritus improvement, and absence of cumulative toxicity provide a new evidence-based systemic option within a historically limited treatment landscape.¹

“Lymphir is an important new tool in the fight against CTCL. It is the only FDA-approved systemic therapy for CTCL in more than 7 years,” concluded Myron Czuczman, MD, Executive Vice President and Chief Medical Officer of Citius Oncology and Citius Pharma, in the news release. “Lymphir's direct tumoricidal activity and transient T-regulatory cell depletion offer a powerful new approach to disease control without cumulative toxicity. As such, Lymphir's clinical profile makes it a compelling treatment option for physicians and patients facing the burden of relapsed or refractory CTCL.”¹

References

1. Citius Oncology Announces U.S. commercial launch of LYMPHIR™, a novel cancer immunotherapy for cutaneous T-Cell lymphoma (CTCL). News release. Citius Oncology. December 1, 2025. Accessed December 2, 2025. https://www.citiusonc.com/news/news-details/2025/Citius-Oncology-Announces-U-S--Commercial-Launch-of-LYMPHIR-a-Novel-Cancer-Immunotherapy-for-Cutaneous-T-Cell-Lymphoma-CTCL/default.aspx
2. Brunner P. Chronic inflammation: what to learn from cutaneous lymphomas. Oral presentation. Presented at: Inflammatory Skin Disease Summit 2025; November 12-15, 2025; New York, New York.