Positive Results from Friedreich's Ataxia Trial Published

Positive Phase 1b/2a trial results for RT001 in patients with Friedreich’s ataxia were published this morning in the online journal Movement Disorders.¹

The article, titled “Randomized, Clinical Trial of RT001: Early Signals of Efficacy in Friedreich’s Ataxia,” highlighted results of the Phase 1b/2a trial, in which early signals of drug effect (including statistically significant improvements in peak exercise workload compared to placebo) were observed with Retrotope’s lead product candidate. Positive safety and tolerability were also reported.

The randomized, double-blind, placebo-controlled, two-dose Phase 1b/2a study randomized 19 patients with Friedreich’s ataxia 2:1 (RT001: placebo) in either a low-dose or high-dose cohort (1.8 or 9.0 g/day), or matching dose of nondeuterated ethyl linoleate as comparator for 28 days. The study met all primary safety, tolerability, and pharmacokinetic (PK) goals in each of the patients who completed the 28-day period of treatment.

RT001 was found to be safe and tolerable with plasma levels approaching saturation by 28 days.

Theresa Zesiewicz, MD, FAAN, Director of the University of South Florida Ataxia Research Center, served as the principal investigator of the study,

“These are the first findings published in a peer-reviewed journal demonstrating that a D-PUFA can show both safety and early indications of possible efficacy over a short treatment window of 28 days in patients with a progressive neurodegenerative disease such as FA,” Dr Zesiewicz said in a press release. “While biological activity was not a primary goal of the study, we are encouraged by the study results and look forward to further progress of the program.”²

RT001 is a deuterated polyunsaturated fatty acid (D-PUFA) that incorporates into mitochondrial and cellular membranes to stabilize them.

“The Phase 1b/2a trial provides an early signal that RT001 may be able to address one of the most important concerns of Friedreich’s ataxia patients, namely, the ability to generate additional energy during exercise and avoid the profound fatigue in performing most tasks,” said Peter G. Milner, MD, Retrotope’s Chief Medical Officer. “Based on these findings and additional positive results from the trial, we intend to move RT001 forward in this disease and have submitted a pivotal study protocol to the US FDA for review.”

Adverse events (AEs) reported in the study were either very mild or not drug related. For the 18 patients who completed the study, there was progress in peak workload during cardiopulmonary exercise testing (CPET) in the drug group versus placebo (0.16 watts/kg; p = 0.008), and there were improvement trends in peak oxygen consumption and stride speed. Additionally, fatty acid metabolites of RT001 were detected and demonstrated that the drug was involved in normal fatty acid processing.

A 19^th subject with a low body mass index experienced steatorrhea while taking the highest dose and discontinued the study. This is a frequent problem associated with high polyunsaturated fatty acid dosing; it is typically self-resolved in several hours.

Study authors conclude that further research into the effect of RT001 in Friedreich's ataxia is warranted.

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References:

1. Zesiewicz T, Heerinckx F, et al. Randomized, clinical trial of RT001: Early signals of efficacy in Friedreich’s ataxia. Movement Disorders. 2018. https://doi.org/10.1002/mds.27353.
2. Retrotope Announces Peer-Reviewed Publication of Positive Phase 1b/2a Findings for RT001 in Friedreich’s Ataxia. Retrotope. http://globenewswire.com/news-release/2018/04/18/1480785/0/en/Retrotope-Announces-Peer-Reviewed-Publication-of-Positive-Phase-1b-2a-Findings-for-RT001-in-Friedreich-s-Ataxia.html?ev=1. Accessed April 18, 2018.