PrimeC scores a milestone in ALS research. The investigational oral therapy significantly reduced neuron-derived TDP-43 — a hallmark protein in ALS — in the phase 2b PARADIGM trial, marking the first placebo-controlled study to show such a reduction. Combined with earlier findings of slowed disease progression and improved survival, the results are fueling plans for a global phase 3 trial.
PrimeC scores a milestone in ALS research
NeuroSense's investigational oral therapy PrimeC has met the primary efficacy endpoint of the phase 2b PARADIGM trial, achieving a statistically significant reduction in neuron-derived TDP-43 compared to placebo in adults with ALS. TDP-43 aggregation is present in over 97% of ALS cases and is considered a defining hallmark of the disease — making this the first randomized, double-blind, placebo-controlled study to demonstrate a treatment-linked reduction in this protein.
The biomarker win builds on previously reported clinical results from PARADIGM, which showed meaningful slowing of functional decline and a striking survival benefit. Published peer-reviewed data in JAMA Neurology also confirmed the drug was generally safe and well tolerated over 18 months. The FDA has cleared NeuroSense to begin enrollment in the global phase 3 PARAGON trial, expected to enroll ~300 participants primarily in the US.
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Why it matters: ALS remains a devastating disease with very limited treatment options. PrimeC's ability to reduce a core disease biomarker while also slowing functional decline and improving survival — all in a controlled trial — is a rare combination in ALS drug development. If confirmed in phase 3, it could represent a meaningful disease-modifying therapy for patients who currently have few choices.
