Results from a Phase 1/2 clinical study support the safety and tolerability of RT001, an investigational therapy for Friedreich’s ataxia. Patients treated with RT001 also were seen to improve in physical functioning tests.
The study, “Randomized, clinical trial of RT001: Early signals of efficacy in Friedreich’s ataxia,” was published in the journal Movement Disorders.
RT001 is an investigational fatty-acid developed by Retrotope that protects mitochondrial and cellular membranes against attacks. This helps to restore mitochondrial function in degenerative diseases such as Friedreich’s ataxia.
In 2016, the U.S. Food and Drug Administration designated RT001 as an orphan drug to advance its development as a possible therapy for Friedreich’s ataxia.
In this Phase 1/2 clinical study (NCT02445794), researchers evaluated the therapy’s effectiveness and pharmacokinetics profile, a measure of how the therapy behaves in the body.
The trial was conducted at the Collaborative Neuroscience Network in Long Beach, California, and at USF Ataxia Research Center in Tampa, Florida.
The study enrolled 18 patients with Friedreich’s ataxia who were randomized to one of two oral doses of RT001 – 1.8 or 9 grams/day – or an inactive control. Treatment continued for 28 days, after which researchers assessed the study’s primary goals of safety and tolerability.
Overall, 13 participants were randomized to treatment with RT001 and six were in the control group.
Additional objectives included identifying the pharmacokinetics of RT001 following single and multiple oral doses and establishing an optimum dose for future studies.
Researchers also assessed changes in the Friedreich’s Ataxia Rating Scale-Neurological score (FARS-Neuro), the timed 25-foot walk, and cardiopulmonary exercise testing.
The results showed that treatment with RT001 was safe and well-tolerated, and the only reported treatment-related adverse event was diarrhea.
RT001 was promptly absorbed, achieving steady levels in blood circulation within the 28 days of treatment. Also, a metabolite of RT001 — a molecule resulting from the metabolism of the treatment — able to penetrate the brain was found in blood circulation on the 28th day.
Treatment with RT001 was associated with improvements in peak workload (fitness) compared to controls, in peak oxygen consumption, and in stride speed. The duration of the study, however, likely was insufficient to detect significant changes in FARS-Neuro scores, which measures progression in FA patients, relative to controls.
Overall, because no approved therapies exist yet for FA, “the observed safety, tolerability, and signs of clinical efficacy make RT001 a good candidate for further, larger clinical trials” in FA, the study concluded.