New Data Show CNM-Au8 Preserved ALS Patient Function & Slowed Disease Progression in the Open-Label Extension of the Phase 2 RESCUE-ALS Trial

Clene Inc. and its wholly owned subsidiary Clene Nanomedicine, Inc., a clinical-stage biopharmaceutical company focused on revolutionizing the treatment of neurodegenerative diseases, recently announced new results showing preserved ALS patient functional score (ALSFRS-R) and delayed time to clinical worsening from the most recent 12-month data cut of the open-label extension (OLE) of the Phase 2 RESCUE ALS trial in people with early amyotrophic lateral sclerosis (ALS) treated with CNM-Au8.

“Clene is pleased to report that CNM-Au8 preserved physical function in the long-term open-label portion of the Phase 2 RESCUE-ALS trial when given over 48-weeks as measured by the ALSFRS-R, a clinical assessment measuring activities such as walking, speaking, breathing, feeding, and dressing independently,” said Rob Etherington, President and CEO of Clene. “Together with improved survival and slowing ALS clinical worsening, these functional changes are meaningful to people living with ALS.”

Study participants in RESCUE-ALS were randomized 1:1 to receive 30 mg of CNM-Au8 or placebo daily for 36 weeks during the double-blind portion of the study, followed by an OLE period that extended treatment indefinitely. The trial randomized 45 participants (n=23 active treatment, n=22 placebo). Thirty-six participants continued into the OLE, including 20 of 21 eligible participants (95%) originally randomized to CNM-Au8, and 16 of 19 eligible (84%) participants originally randomized to placebo. The OLE analyses compared participants originally randomized to placebo who experienced a nine-month delay in treatment initiation with CNM-Au8 to participants treated daily with CNM-Au8 from randomization.

New Findings from RESCUE-ALS OLE through 120 Weeks
The current data cut represents a 12-month minimum follow-up for OLE participants from the last-patient last-visit from the 36-week double-blind treatment period through July 14, 2022. The rates of change for ALSFRS-R were compared post hoc with a random slopes model.

  • Statistically significant difference in ALSFRS-R slope from day 1 (randomization) to week 48: among participants originally randomized to active compared to participants originally randomized to placebo (p=0.0159; 2.6-point difference in ALSFRS-R at week 48). This represents an extension of the original double-blind period in which placebo-to-CNM-Au8 OLE participants had not yet reached effective drug concentrations.
  • Statistically significant difference in ALSFRS-R slope from week 60 to week 120 comparing participants originally randomized to active or placebo. Analyses were conducted starting at 24-weeks in open-label to ensure that ex-placebo participants who switched to CNM-Au8 in the OLE were at steady-state CNM-Au8 concentrations (p=0.0057; 6.0-point difference in ALSFRS-R at week 120).
  • Statistically significant delay in time to ALS clinical worsening including death, tracheostomy, initiation of ventilatory support, or feeding tube insertion through 120 weeks (Cox hazard ratio 0.478, 95% CI: 0.225 to 1.015, log-rank p=0.0494). The risk of ALS progression was less than half for those originally receiving CNM-Au8 compared to those originally receiving placebo.

Professor Steve Vucic, PhD, DSc, Northcott Chair of Neurology, The University of Sydney, and a co-investigator of the RESCUE-ALS study, said “The totality of data generated from the CNM-Au8 ALS clinical program and the long-term patient benefits are highly encouraging. It is extraordinarily notable that a nine-month difference in treatment initiation with CNM-Au8 substantially preserved long-term function in patients originally receiving CNM-Au8 compared to patients originally receiving placebo during long-term follow-up. With its favorable tolerability profile and ability to be used alone or in combination with other ALS therapies, early treatment with CNM-Au8 may play an essential role in the treatment of ALS. We look forward to presenting these data at upcoming scientific congresses.”

“The open-label data at 48 weeks and through 120 weeks from randomization suggests that CNM-Au8 has the ability to meaningfully improve patient daily functional status over longer periods of time, together with sustained treatment effects on ALS disease progression and survival,” added Professor Matthew Kiernan, PhD, DSc, Bushell Chair of Neurology, University of Sydney, and one of the trial’s clinical advisors. “It is exciting to see such long-term data not only reinforcing the potential of CNM-Au8 as a therapy for ALS but also confirming its excellent safety profile.”

These new data are summarized and posted at

RESCUE-ALS was a Phase 2 multi-center, randomized, double-blind, parallel-group, placebo-controlled trial, investigating the efficacy, safety, pharmacokinetics and pharmacodynamics of CNM-Au8 in 45 participants (73% limb onset, 27% bulbar onset) with early ALS over a 36-week treatment period. The primary endpoint was the percent change in the summated motor unit index (MUNIX) scores to week 36. The primary blinded comparative period was followed by an open-label extension (OLE) in which all participants received 30 mg of CNM-Au8 once-daily, with 90% (36 of 45 patients) entering the OLE. Clene announced topline results for RESCUE-ALS on November 2, 2021.

CNM-Au8 is an oral suspension of gold nanocrystals developed to restore neuronal health and function by increasing energy production and utilization. The catalytically active nanocrystals of CNM-Au8 drive critical cellular energy producing reactions that enable neuroprotection and remyelination by increasing neuronal and glial resilience to disease-relevant stressors. CNM-Au8® is a federally registered trademark of Clene Nanomedicine, Inc.

Clene is a clinical-stage biopharmaceutical company focused on revolutionizing the treatment of neurodegenerative disease by targeting energetic failure, an underlying cause of many neurological diseases. The company is based in Salt Lake City, Utah, with R&D and manufacturing operations in Maryland. For more information, visit