At this year’s annual meeting of the American Society of Gene and Cell Therapy (ASGCT), French biotechnology company EG 427 will share recent advances in the development of its recombinant, non-replicating HSV-1 (nrHSV-1) vector technology. The company plans to present two posters at the meeting, which is being held May 13-17 in New Orleans.
EG 427 is developing its nrHSV-1 vector technology—engineered versions of the herpes simplex virus type 1—for use in neurology applications. The company’s vectors are developed using its proprietary HERMES platform and are designed to carry large payloads of over 30 kb as well as for long-term expression.
One poster at the meeting will describe an nrHSV-1 vector containing two different transgenes controlled by independent regulatory elements in different epigenetic regions of the HSV-1 genome. Both in vitro and in vivo studies have shown that the vector technology allows the two transgenes to be expressed with different duration patterns. Specifically, the transgene that was inserted outside of the latency region had a short expression duration, while the transgene inserted in the latency region was stably expressed at tested time points.
“Our ability to offer two transgenes with independent expression profiles in one vector is a huge advantage over other vector technologies, especially when we see the AAV field struggling with multiple vector constructs to deliver a single transgene,” said Teddy Jégu, PhD, EG 427’s vp of research. “Our vision is to be able to develop a single vector with, for example, the ability to delete genes in vivo, through a transient expression of gene editing proteins, and to replace with a corrected gene with the capacity to deliver long-term expression to treat autosomal dominant disease.”
The second poster will highlight the development of an nrHSV-1 vector that broadly targets cortical neurons in the striatum. The vector expresses the mGreenLantern reporter gene under the control of the CAG promoter. The company will share data that shows that when the vector was injected into mice striatum, there was evidence of high-level transgene expression in layer V cortical neurons, and stable expression levels were seen at least six weeks after treatment. Furthermore, they also show that the cells that expressed mGreenLantern in the cortex were exclusively neurons.
EG 47 already has at least one therapy in human trials. Earlier this year, the company dosed its first patient in a Phase I/II study for its lead candidate, EG110A. The therapy is intended to address severe bladder diseases, including overactive bladder. For the current trial, it is being tested in patients with neurogenic detrusor overactivity (NDO) in people with spinal cord injuries. The treatment works by selectively silencing the signals of key bladder sensory neurons that are responsible for the bladder muscle overactivity, while preserving motor neurons and retaining normal bladder function.
For the trial, the company plans to enroll a total of 16 adult participants with NDO following spinal cord injury with persistent urinary incontinence. Participants receive a single treatment course consisting of multiple intradetrusor injections of EG110A. The study is being conducted at four U.S. institutions located in California, Michigan, Pennsylvania, and Texas.
The post ASGCT 2025: EG 427 Makes Strides in Non-Replicative HSV-1 Vectors for Neurological Therapies appeared first on GEN - Genetic Engineering and Biotechnology News.
EG 427 is developing its nrHSV-1 vector technology—engineered versions of the herpes simplex virus type 1—for use in neurology applications. The company’s vectors are developed using its proprietary HERMES platform and are designed to carry large payloads of over 30 kb as well as for long-term expression.
One poster at the meeting will describe an nrHSV-1 vector containing two different transgenes controlled by independent regulatory elements in different epigenetic regions of the HSV-1 genome. Both in vitro and in vivo studies have shown that the vector technology allows the two transgenes to be expressed with different duration patterns. Specifically, the transgene that was inserted outside of the latency region had a short expression duration, while the transgene inserted in the latency region was stably expressed at tested time points.
“Our ability to offer two transgenes with independent expression profiles in one vector is a huge advantage over other vector technologies, especially when we see the AAV field struggling with multiple vector constructs to deliver a single transgene,” said Teddy Jégu, PhD, EG 427’s vp of research. “Our vision is to be able to develop a single vector with, for example, the ability to delete genes in vivo, through a transient expression of gene editing proteins, and to replace with a corrected gene with the capacity to deliver long-term expression to treat autosomal dominant disease.”
The second poster will highlight the development of an nrHSV-1 vector that broadly targets cortical neurons in the striatum. The vector expresses the mGreenLantern reporter gene under the control of the CAG promoter. The company will share data that shows that when the vector was injected into mice striatum, there was evidence of high-level transgene expression in layer V cortical neurons, and stable expression levels were seen at least six weeks after treatment. Furthermore, they also show that the cells that expressed mGreenLantern in the cortex were exclusively neurons.
EG 47 already has at least one therapy in human trials. Earlier this year, the company dosed its first patient in a Phase I/II study for its lead candidate, EG110A. The therapy is intended to address severe bladder diseases, including overactive bladder. For the current trial, it is being tested in patients with neurogenic detrusor overactivity (NDO) in people with spinal cord injuries. The treatment works by selectively silencing the signals of key bladder sensory neurons that are responsible for the bladder muscle overactivity, while preserving motor neurons and retaining normal bladder function.
For the trial, the company plans to enroll a total of 16 adult participants with NDO following spinal cord injury with persistent urinary incontinence. Participants receive a single treatment course consisting of multiple intradetrusor injections of EG110A. The study is being conducted at four U.S. institutions located in California, Michigan, Pennsylvania, and Texas.
The post ASGCT 2025: EG 427 Makes Strides in Non-Replicative HSV-1 Vectors for Neurological Therapies appeared first on GEN - Genetic Engineering and Biotechnology News.