Citius Pharmaceuticals is planning to spin out its immune asset I/ONTAK into a separate publicly-traded entity, pending the FDA’s verdict on the candidate, due July 28.

I/ONTAK, which Citius is proposing as a treatment for T-cell lymphoma, is a reformulation of Eisai’s Ontak (denileukin diftitox), which won initial approval in 1999 for the same indication. Citius’ candidate is a recombinant fusion protein that combines a diphtheria toxin with the interleukin-2 protein. It works by specifically binding to IL-2 receptors to precisely deliver its toxic payload, thereby preventing protein synthesis in malignant T cells.

I/ONTAK also targets the immunosuppressive regulatory T cells, which in turn allows the body to produce a stronger immune response against the cancer.

The therapeutic fusion protein is approved in Japan, where it is marketed under the brand name Lymphir.

The FDA accepted Citius’ Biologics License Application for I/ONTAK in December 2022 and initially gave it a target action date of Sept. 28, 2023. The regulator later shortened its review period and provided the updated deadline of July 28. 

Citius is backing I/ONTAK’s regulatory bid with data from a pivotal Phase III study. The company released positive topline data from this trial in April 2022, demonstrating that the candidate can elicit an overall response rate of 42.3%, indicating that nearly half of patients show partial or complete response to treatment.

Source: bioSpace.com