ELX-02, Potential CF Nonsense Mutation Therapy, on FDA Fast Track

Marisa Wexler, MS avatar

by Marisa Wexler, MS |

Share this article:

Share article via email
CF Awareness Month | Cystic Fibrosis News Today | illustration of newsworthy announcement

The U.S. Food and Drug Administration (FDA) has given fast track designation to ELX-02, an investigational treatment for people with cystic fibrosis (CF) caused by nonsense mutations.

This FDA designation aims to speed the development and regulatory review of potential treatments for serious or life-threatening diseases with an unmet medical need. It gives Eloxx Pharmaceuticals access to more frequent meetings with the FDA during its therapy’s development process, with the overall aim of getting effective therapies to people needing them more quickly.

“We are delighted to receive Fast Track Designation from the FDA for ELX-02 as the need for patients remains significant. The ability to have greater access to the FDA and their guidance on the regulatory pathway for ELX-02 can help provide the ability to work with the urgency needed on behalf of CF patients with nonsense mutations,” Sumit Aggarwal, president and CEO of Eloxx, said in a press release.

Recommended Reading
ELX-02 organoid study

ELX-02 Restores CFTR Activity in Organoids With G542X Mutations, Study Finds

CF is caused by mutations in the CFTR gene. Different types of mutations have different specific effects, though all ultimately lead to a lack of function in the CFTR protein encoded by the gene.

A nonsense mutation is a change in the genetic code that creates a “stop” signal in the middle of a gene — kind of like putting a period in the middle of a sentence. When a cell’s protein-making machinery “reads” the gene, it stops at the early signal, making a shortened protein that gets quickly degraded. ELX-02 aims to allow this molecular machinery to “read through” the early stop signal and make a full-length, working protein.

Eloxx is sponsoring two similar and open-label Phase 2 clinical trials, called EL-004 (NCT04126473) and EL-012 (NCT04135495), testing ELX-02 in people with CF who have at least one G542X mutation — the most common CF-causing nonsense mutation. These studies are currently recruiting eligible patients at sites in the U.S. (ages 18 and older), and in Australia, Germany, and Israel (16 and  older).

Trial participants are being given four increasing doses (the highest being individualized) of ELX-02, administered via a once-daily subcutaneous (under-the-skin) injection. A fifth treatment group, also patients with at least one G542X mutation, has been added to test ELX-02 in combination with Kalydeco (ivacaftor), an approved CFTR potentiator therapy by Vertex.

Both trials’ main goals are to determine ELX-02’s safety profile and pharmacological properties. The medication’s effect on lung function and sweat chloride levels also will be assessed. Data from the first four treatment groups are expected by year’s end, Eloxx reported earlier.

ELX-02 has also been designated an orphan drug by the FDA, and an orphan medicinal product by the European Medicines Agency.