ALS: The MIROCALS Trial Paves the Way for a New Treatment
The results of the European MIROCALS trial provide new insights into a promising therapeutic approach for Amyotrophic Lateral Sclerosis (ALS). Low-dose interleukin-2 could slow disease progression in certain patients. A study supported by AFM-Téléthon and its laboratory, Généthon, through its biobank.
A Major Milestone in ALS Research
Published in The Lancet, the MIROCALS study (Modifying Immune Responses and Outcomes in ALS) represents a major breakthrough in ALS research. The trial assessed the efficacy and safety of low-dose interleukin-2 (IL-2LD), a molecule known for its ability to modulate the immune system.
Conducted between 2017 and 2019 in 220 newly diagnosed patients treated with riluzole, the protocol demonstrated good tolerability of IL-2LD. While the primary survival analysis did not demonstrate a significant overall effect, a targeted analysis of participants with low levels of a neuronal biomarker (pNFH) showed a reduction in mortality risk of over 40%.
Understanding ALS
Amyotrophic Lateral Sclerosis, also known as Charcot’s disease, is a rare and progressive neurodegenerative disorder that affects motor neurons. It leads to the gradual paralysis of muscles, generally sparing sensory functions.
Each year in Europe, around 45,000 people live with ALS. The disease progresses at varying rates, but more than half of patients die within two to three years of diagnosis. To date, there is no cure. Riluzole remains the only approved medication, with a modest impact on disease progression.
A Promising Immunomodulatory Strategy
IL-2LD works by increasing regulatory T cells (Tregs), which play a key role in regulating immune responses and limiting chronic inflammation. These findings reinforce the hypothesis that the immune system could be a relevant target for slowing ALS progression.
Although this molecule is not yet approved for this indication, data from the MIROCALS trial support the launch of a larger phase 3 clinical trial.
A Structuring European Partnership, with Decisive French Support
Led by the Nîmes University Hospital and coordinated by Dr. Gilbert Bensimon (Nîmes University Hospital, Sorbonne University, AP-HP) and Professor Peter Nigel Leigh (Universities of Brighton and Sussex), the MIROCALS project brought together a high-level European consortium.
AFM-Telethon provided financial support for the study. Genethon, its laboratory, contributed logistical support through its DNA biobank—one of the largest in Europe—offering its expertise in the processing and storage of samples from the 220 patients enrolled in the trial.