ARTHEx Biotech, a biotechnology company in the clinical stage of development, has recently made a significant announcement regarding its financing efforts. The company focuses on creating targeted RNA medicines, particularly for rare genetic neuromuscular disorders. They have completed an extended Series B financing round, gathering a total of $87 million.
This funding effort was notably led by Bpifrance, a new investor, as part of their Large Venture and InnoBio investment strategies. Existing shareholders also supported this initiative, including companies like AdBio Partners, CDTI Innovación (through its Innvierte program), Columbus Venture Partners, the European Innovation Council (EIC), Hadean Ventures, Invivo Partners, and Sound Bioventures.
The money raised from this financing will play a crucial role in advancing the global clinical development of ARTHEx’s leading program, ATX-01, specifically designed to treat Myotonic Dystrophy Type 1 (DM1). As part of this effort, the company is currently involved in a Phase I/IIa clinical study called ArthemiRTM and is also preparing for an open-label extension that will support future registrational studies. These steps are vital for ensuring that their treatment is effective and can eventually reach patients who need it.
ATX-01 works by using an innovative approach called an anti-miR oligonucleotide. This means it is designed to inhibit a specific microRNA known as miR-23b. In simpler terms, microRNAs are small molecules in our cells that can regulate the expression of proteins. In patients with DM1, the problem arises because miR-23b acts as a natural repressor of a protein called MBNL. When MBNL is not functioning correctly, it can lead to significant complications.
The challenges faced by DM1 patients stem from two main issues. First, the upregulation of miR-23b reduces the production of MBNL proteins. Second, MBNL proteins can get sequestered, or trapped, in a toxic molecule called DMPK mRNA, which causes further complications in the cellular processes that are essential for normal function. As a result, patients with DM1 experience various symptoms due to these disruptions.
By targeting and inhibiting miR-23b, ARTHEx aims to increase the levels of MBNL in the cells. This process has been shown to reduce the formation of toxic DMPK mRNA foci, which are clusters of malfunctioning molecules that contribute to the disease. This unique dual action—boosting MBNL production while limiting the toxic buildup—leads to more free MBNL in the system. This increase is essential because it assists in correcting splicing abnormalities in the cells, which are key to restoring normal cellular functions.
KEY QUOTES:
“We believe ATX-01 could be a game-changer for patients suffering from DM1 on the basis of novel science and impressive data generated so far. We are excited to partner with ARTHEx as the company reaches clinical proof-of-concept stage and look forward to supporting Frederic and team in their efforts to build a leading franchise of precision RNA medicines.”
Laurent Higueret, Deputy Director at Bpifrance’s Large Venture Fund
“The approach developed by ARTHEx for DM1 aiming at targeting miR-23b has demonstrated compelling in vitro and in vivo results. The dual mechanism of action of ATX-01 offers real potential to be the best-in-class treatment for DM1. In addition, the Company’s delivery platform enables uptake into multiple tissues affected by DM1, allowing ATX-01 to go beyond the muscle, treating the whole disease and not just the symptomatology. We are eager to see initial clinical data in 2026.”
Benoit Barteau, Investment Director at Bpifrance’s InnoBio funds
“This financing marks an important milestone for ARTHEx and underscores the strength of our approach in DM1 and our emerging delivery platform, with its potential to deliver nucleic acid-based therapies beyond muscle. We are well positioned to advance ATX-01 toward a registrational study for DM1, while continuing to expand our pipeline across areas of high unmet need in muscular, CNS, cardiac conditions.”
Frédéric Legros, Chairman and CEO
“Arthex has made significant progress over the past years, advancing both its science and its clinical program. All investors are very pleased to continue supporting the company, and we believe that reinforcing its position through this financing is an important step to enable the next phase of its development.”
Jose Mesa, Partner at Columbus Venture Partners, initial lead investor of the Series B
