Rgenta Therapeutics Announces Presentation of Preclinical Data from Proprietary RSwitch Technology

WOBURN, Mass., April 30, 2025 /PRNewswire/ -- Rgenta Therapeutics, a clinical-stage biotechnology company pioneering the development of a new class of oral small molecules targeting RNA and RNA regulation for oncology and neurological disorders, announced today that preclinical data will be presented on its proprietary RSwitch technology, which enables the fine-tuning of transgene levels in gene and cell therapy applications, at the American Society of Gene And Cell Therapy (ASGCT) 28th Annual Meeting, which will be held from May 13 -17th, 2025, in New Orleans, LA. 

Title: RSwitch Enabled Gene Therapy to Fine Tune Frataxin Expression for the Treatment of Friedrich's Ataxia, Samuel A. Hasson, Jon Dempersmier, Mariam Elhawary, Diane Hamann, Ian McLachlan, Chris Yates, Travis Wager, and Simon Xi 

 RSwitch is a proprietary regulatable gene therapy system that enables oral, small molecule drug control of transgene levels in gene and cell therapy applications. RSwitch encodes a "dimmer" switch that makes the expression of transgene dependent on the administration of an oral small molecule drug that controls the system. Only when the drug is administered is the system activated. Furthermore, the level of gene expression is dependent on how much drug is administered. This precise gene control has the potential to enable fine control of the expression of a therapeutic protein.

Larimar Therapeutics Reports First Quarter 2025 Financial Results

BALA CYNWYD, Pa., April 30, 2025 (GLOBE NEWSWIRE) -- Larimar Therapeutics, Inc. (Larimar) (Nasdaq: LRMR), a clinical-stage biotechnology company focused on developing treatments for complex rare diseases, today reported its first quarter 2025 operating and financial results.

Completed Dosing of Adolescents in Pharmacokinetic (PK) Run-In Study.

Potential for Accelerated Approval Pathway Based on Skin FXN Concentrations. 

Planned Upcoming Regulatory Discussions. 

50 mg OLE Data Expected in September 2025. 

Planned Transition to Lyophilized Form of Nomlabofusp. 

BLA Submission and Initiation of Global Phase 3 Study on Track

Gene circuits enable more precise control of gene therapy

Anne Trafton | MIT News Publication Date:April 28, 2025 

Very few gene therapy treatments have been approved by the FDA. One of the challenges to developing these treatments has been achieving control over how much the new gene is expressed in cells — too little and it won’t succeed, too much and it could cause serious side effects. 

To demonstrate this system, the researchers designed ComMAND circuits that could deliver the gene FXN, which is mutated in Friedreich’s ataxia — a disorder that affects the heart and nervous system. They also delivered the gene Fmr1, whose dysfunction causes fragile X syndrome. In tests in human cells, they showed that they could tune gene expression levels to about eight times the levels normally seen in healthy cells. 

Without ComMAND, gene expression was more than 50 times the normal level, which could pose safety risks. Further tests in animal models would be needed to determine the optimal levels, the researchers say.

Model-guided design of microRNA-based gene circuits supports precise dosage of transgenic cargoes into diverse primary cells

Model-guided design of microRNA-based gene circuits supports precise dosage of transgenic cargoes into diverse primary cells. Love, Kasey S. et al., Cell Systems, Volume 0, Issue 0, 101269 DOI: 10.1016/j.cels.2025.101269

In a therapeutic context, supraphysiological expression of transgenes can compromise engineered phenotypes and lead to toxicity. To ensure a narrow range of transgene expression, we developed a single-transcript, microRNA-based incoherent feedforward loop called compact microRNA-mediated attenuator of noise and dosage (ComMAND).

ComMAND effectively sets levels of the clinically relevant transgenes frataxin (FXN) and fragile X messenger ribonucleoprotein 1 (Fmr1) within a narrow window.