Citius Pharma receives FDA approval for immunotherapy targeting rare blood cancer

Citius Pharmaceuticals has announced that the FDA has granted approval to Lymphir (denileukin diftitox-cxdl) as a treatment for relapsed or refractory (r/r) CTCL patients that have previously received at least one course of a systemic therapy.

The approval of Lymphir, which is expected to launch in the US within the next five months, is the first for a targeted systemic therapy targeting r/r CTCL since 2018. It also marks the first FDA approval for Citius Pharma.

CTCL is the most common form of cutaneous non-Hodgkin lymphoma (NHL), a rare form of cancer caused by malignant T cells that affects the skin. There is currently no cure for advanced forms of CTCL except for stem cell transplantation, for which only a small fraction of patients qualify.

Patients diagnosed with this type of cancer typically cycle through multiple therapies until becoming resistant or experiencing the progression of the disease. Most of these options are aimed at managing the disease by targeting symptoms, such as reducing and controlling skin plaques and itching.

Lymphir is the only systemic treatment for r/r CTCL to target the IL-2 receptor on malignant T cells and regulatory T cells, providing another alternative for patients who have failed to respond or stopped responding to other lines of treatment.

“We believe Lymphir's unique IL-2 receptor-targeted treatment, which kills tumor cells directly, and concurrently depletes host Tregs in order to boost the body's immune response, is an important differentiator and offers clinically meaningful benefits to a significant percentage of r/r patients. As the only IL-2 receptor-targeted immunotherapy for CTCL, Lymphir provides a novel and non-cross-resistant treatment option without cumulative toxicity for patients for whom symptomatic skin involvement interferes with their daily quality of life,” said Myron Czuczman, Chief Medical Officer of Citius Pharmaceuticals.

The approval of Lymphir was based on positive data from a phase 3 clinical trial that recruited 69 CTCL patients who had previously received at least one systemic treatment. The results showed an overall response rate (ORR) of 36%, and a reduction in skin disease in 84% of patients.

Importantly, the median time for patients to respond to the treatment was under two months, with approximately 70% of patients seeing results after one or two cycles of treatment.

“Given the long-term nature of the disease, (...) it is vital to get this skin involvement under control. Lymphir is the first therapeutic option in many years to offer hope of reducing skin disease, bringing us one step closer to filling the need for CTCL patients, particularly those that are not able to complete or continue prior therapies,” said Francine Foss, Professor of Hematology and Director of the Multidisciplinary T-cell Lymphoma Program at the Yale Cancer Center.