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The United States Food and Drug Administration (FDA) has granted orphan drug and rare pediatric disease designations to LX1004, an investigational gene therapy for CLN2 disease, also known as late childhood Batten disease.

“The two designations granted to LX1004 underscore the critical importance and urgency of advancing new therapeutic approaches for CLN2 Batten disease, a fatal genetic disease affecting the central nervous system (CNS)”, R. Nolan Townsend, CEO of Therapeutic Lexeo, the developer of the therapy, said in a Press release.

Townsend said Lexeo was continuing development of the LX1004 “in the hope of making it available to patients as soon as possible.”

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LX1004 is an adeno-associated virus (AAV) mediated gene therapy. It is designed to provide a healthy copy of CLN2, the gene that provides instructions to make an enzyme called tripeptidyl peptidase 1 (TPP1), to the central nervous system, which includes the brain and spinal cord.

When CLN2 is mutated, as in late childhood Batten disease, a lack of TTP1 kills cells – especially neurons or nerve cells. This results in symptoms such as seizures and loss of motor skills and cognitive abilities.

The company has completed a Phase 1 clinical trial of LX1004 and plans to move into a pivotal study in 2022 to demonstrate the effectiveness of the therapy.

“We are encouraged by the results of the Phase I study of LX1004 which have reached clinical proof of concept, and we look forward to advancing the program through further clinical development,” said Townsend.

A program with the orphan drug designation is eligible for incentives to accelerate the development of therapy. In addition, Lexeo may submit a biologics license application to request authorization to market the LX1004. If approved, the business may be eligible to obtain a Priority Review Voucher to expedite the therapy review process.

Lexeo was founded on the basis of gene therapy research conducted at Weill Cornell Medicine in New York, with which the company said it has a partnership.

Weill’s researchers had led a previous phase 1 clinical trial (NCT00151216) assess the security of the delivery CLN2 gene using an AAV vector in the central nervous system. This study, completed in June 2019, involved 10 patients with late infantile Batten disease.

Results showed that neurological decline was reduced in patients who received gene therapy compared to controls, suggesting that the strategy has the potential to delay disease progression. Scientists said the results warrant further studies to assess the safety and efficacy of AAV-mediated gene therapy.

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