FDA Approves Citius Pharmaceuticals’ Lymphir for Relapsed or Refractory Cutaneous T-Cell Lymphoma

Image Credit: Adobe Stock Images/LASZLO

The FDA has approved Citius Pharmaceuticals’ Lymphir to treat relapsed or refractory cutaneous T-cell lymphoma (CTCL). According to the company, the drug demonstrated efficacy in reducing skin tumor burden, improving pruritus, and achieving rapid response times without cumulative toxicity in clinical trials. This approval marks the first treatment in Citius’ pipeline to receive FDA approval.¹

"Lymphir offers new hope for patients suffering from cutaneous T-cell lymphoma, a rare and chronic cancer characterized by debilitating skin lesions and severe itching. This approval is a significant milestone for CTCL patients. The introduction of Lymphir, with its potential to rapidly reduce skin disease and control symptomatic itching without cumulative toxicity, is expected to expand the CTCL treatment landscape and grow the overall market, currently estimated to be $300-$400 million," said Leonard Mazur, CEO, Citius Pharmaceuticals, in a press release.

The approval was based on results from the open-label, single-arm, multicenter Study 302 trial, which enrolled patients with relapsed or refractory (r/r) Stage I to IV CTLC to evaluate the efficacy of Lymphir. The study included 69 patients, 65% of whom were male, 73% were White, 19% Black or African American, 1% Asian, and 14% Hispanic or Latino. Patients received a median average of four prior treatments, which included skin-directed and systemic therapies. Prior therapies consisted of photodynamic therapy, total skin electron beam therapy, systemic retinoids, methotrexate/pralatrexate, histone deacetylase inhibitor, brentuximab vedotin, and mogamulizumab.

Efficacy results found a complete response rate of 9% and a partial response rate of 27%. Additionally, the results found an overall response rate of 36%, with 52% of patients showing a six-month duration or response and 20% demonstrated one full year.

Common adverse events (AEs) included increased transaminases, albumin decreased, nausea, edema, hemoglobin decreased, fatigue, musculoskeletal pain, rash, chills, constipation, pyrexia, and capillary leak syndrome. Lymphir’s safety profile remained consistent with the known safety profile for denileukin diftitox.¹

"Lymphir, with an initial indication in the treatment of CTCL, is the first of our pipeline candidates to receive FDA approval. Citius is dedicated to working closely with healthcare providers to ensure that all r/r CTCL patients have timely access to this important new therapy. We are preparing to launch Lymphir in the US market within the next five months," said Mazur, in the press release.

In June, Pharm Exec spoke with Mazur regarding the FDA accepting the Biologics License Application for Lymphir. Prior to this, Citius received a Complete Response Letter from the FDA regarding Lymphir in July 2023, citing a validation procedure that had yet to be completed from a prior test that was going to run past the intended Prescription Drug User Fee Act date.²

“I think everybody thought that the agency would give us an approval condition upon completing that validation test and not go to market until that could happen, but the agency chose to go the other way,” said Mazur, in an interview with Pharm Exec.

According to the Leukemia and Lymphoma Society, there are around 879,242 people living with or in remission from lymphoma in the United States, including 159,867 with Hodgkin lymphoma and 722,631 with non-Hodgkin lymphoma.³

"We are grateful to the clinicians, patients, and researchers who contributed to the development of Lymphir. 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 Stage I-III r/r patients for whom symptomatic skin involvement interferes with their daily quality of life. Lymphir's median time-to-response of only 1.4 months (min, max: 0.7, 5.6) offers many patients rapid skin relief," said Myron Czuczman, MD, chief medical officer, Citius Pharmaceuticals, in the press release.

References

1. Citius Pharmaceuticals Receives FDA Approval For LYMPHIR™ (Denileukin Diftitox-Cxdl) Immunotherapy For The Treatment Of Adults With Relapsed Or Refractory Cutaneous T-Cell Lymphoma. Citius Pharma. August 8, 2024. Accessed August 9, 2024. https://citiuspharma.com/investors/news-media/news/release-details/2024/Citius-Pharmaceuticals-Receives-FDA-Approval-for-LYMPHIR-denileukin-diftitox-cxdl-Immunotherapy-for-the-Treatment-of-Adults-with-Relapsed-or-Refractory-Cutaneous-T-Cell-Lymphoma/default.aspx

2. Citius Pharmaceuticals Co-Founder and CEO Discusses the Recently Accepted Biologics License Application of Lymphir for the Treatment of Relapsed/Refractory CTCL. PharmExec. June 28, 2024. Accessed August 9, 2024. https://www.pharmexec.com/view/citius-pharmaceuticals-co-founder-ceo-discusses-recently-accepted-biologics-license-application-lymphir-for-the-treatment-relapsed-refractory-ctcl

3. FACTS AND STATISTICS OVERVIEW. Leukemia & Lymphoma Society. Accessed August 9, 2024. https://www.lls.org/facts-and-statistics/facts-and-statistics-overview#:~:text=Hodgkin%20(NHL)%20Lymphoma-,New%20Cases,the%20period%202012%20to%202018.