Neurosense Therapeutics plans to enroll 70 patients with fast-progressing amyotrophic lateral sclerosis (ALS) in its planned Phase IIb trial of PrimeC, CEO Alon Ben-Noon says. The trial will randomise patients 2:1 between PrimeC and placebo during a blinded six-month treatment period, followed by a six-month, open-label treatment period, he adds.
PrimeC is an extended-release, fixed-dose oral formulation composed of celecoxib and ciprofloxacin, both of which have FDA-approval, that targets motor neuron degeneration and neuroinflammation to potentially slow ALS progression. On 21 March, NeuroSense announced plans to initiate the Phase IIb multi-national, randomised control trial in Q2 this year, but further public details have been limited.
The Phase IIb trial, which has planned sites in the US, Israel and Europe, expects results in Q2 next year, Ben-Noon tells Clinical Trials Arena. Pending study results and regulatory guidance, NeuroSense will aim to begin a subsequent Phase III trial in H2 the same year, he adds.
ALS is a rare, neurodegenerative disease characterised by the death of motor neurons with an average life expectancy of just four years after diagnosis. NeuroSense previously announced it will also begin a Phase I trial (NCT05232461) later this month of an updated formulation of PrimeC, which it will use in the upcoming Phase IIb.
ALS biomarkers as primary endpoints
As co-primary endpoints, the planned Phase IIb trial will measure two ALS biomarkers: neuroinflammation and TDP-43 accumulation, Ben-Noon says. Neuroinflammation is a hallmark characteristic of ALS, and TDP-43 is a protein implicated in the disease’s pathology.
“The trial is powered to over 90% to achieve these primary endpoints,” Ben-Noon says. “We are very confident in what we are doing here because, in a very small sample size, we saw a statistically significant changes in these biomarkers.”
In a previous, open-label Phase IIa ALS trial (NCT04165850), PrimeC was found to be safe and tolerable with significant changes in TDP-43 protein following treatment. The 15-patient, 12-month study also found patients treated with PrimeC declined in progression more slowly than historical controls.
In the ALS drug development field, there has been a significant push to develop biomarkers correlated with disease outcomes. Clinical Trials Arena previously reported BrainStorm Cell Therapeutics’ plans to develop stem cells from participants in its Phase III ALS trial, testing a possible a genetic link to ALS progression.
Measuring disease progression
The Phase IIb study’s secondary endpoints will include the ALS Functional Rating Scale (ALSFRS) and vital capacity, Ben-Noon says. ALSFRS is among the most common assessments of disease progression in ALS clinical trials, and vital capacity measures the greatest volume of air expelled from the lungs after taking the deepest possible breath.
Looking ahead to a possible Phase III trial, Ben-Noon says the company is making strong progress in manufacturing capabilities for PrimeC. “We’re already prepared for a manufacturing scale suitable for a Phase III study, and we’re also building our capabilities to be able to manufacture PrimeC in the ALS market.”
NeuroSense’s Phase IIb trial adds another important ALS trial to what is shaping to be a busy year in ALS drug development. Just last week, FDA Advisory Committee panelists narrowly voted against an ALS approval for Amylyx’s AMX0035 as the treatment awaits its June 29 PDUFA date. Meanwhile, the challenges of running an ALS clinical trial and the high unmet need for this devastating disease still loom large.