NeuroPace announced preliminary one-year results from its NAUTILUS study, the first clinical trial evaluating neuromodulation therapy for idiopathic generalized epilepsy (IGE). While the study met its primary safety endpoint, the effectiveness results present a nuanced picture that could still support regulatory approval for a targeted patient population.
Safety Profile Confirmed
The NAUTILUS study successfully achieved its primary 12-week post-implant safety endpoint, demonstrating a low rate of serious adverse events related to the device and implant procedure. This outcome aligns with the established safety profile of the RNS System, which is already FDA-approved for focal epilepsy treatment.
Mixed Effectiveness Results Show Promise in Key Subgroup
The study did not reach statistical significance for its primary effectiveness endpoint in the overall study population, which measured time to a second generalized tonic-clonic seizure comparing active stimulation to sham stimulation groups. However, the data revealed a clinically meaningful and highly statistically significant response within a subgroup of patients with lower baseline frequency of generalized tonic-clonic seizures, representing the majority of trial participants.
"We are very encouraged by the NAUTILUS study results, which demonstrated statistically significant seizure reduction in a key and substantial patient subgroup along with durable improvements across multiple secondary endpoints," said Dr. Martha Morrell, NeuroPace Chief Medical Officer.
Secondary Endpoints Show Robust Clinical Benefits
Across the entire trial population, secondary measures including median percent seizure reduction, responder rates, and improvement in seizure-free days showed numerically robust and clinically meaningful improvements over the first year of treatment. These improvements continued in patients who progressed to the second year of the study.
Notably, the preliminary one-year data showed more favorable rates of median seizure reduction compared to the company's randomized controlled trial in focal epilepsy that led to FDA approval. Patients who completed more than 12 months in the study demonstrated continued clinical improvement over time, consistent with prior findings from the RNS System in focal epilepsy populations.
Study Design and Patient Population
The NAUTILUS study is a prospective, multicenter, randomized, single-blind, sham-stimulation controlled trial that enrolled 100 participants, with 87 undergoing implantation of the RNS Neurostimulator and Leads across 23 epilepsy centers in the United States. Patients had drug-resistant idiopathic generalized epilepsy with a high burden of generalized tonic-clonic seizures, described as the most severe and dangerous seizure type.
NeuroPace received FDA Breakthrough Device Designation in 2021 for the potential use of its RNS System to treat IGE. The trial continues through completion of two years after device implant, with prespecified collection of safety and effectiveness data.
Regulatory Strategy and Next Steps
The company plans to submit the full dataset to the FDA and for peer-reviewed publication. NeuroPace will engage with the FDA to discuss regulatory pathways based on the data, which may include utilizing the overall median seizure reduction data across the full study population or pursuing a more targeted indication focused on patients with lower baseline seizure frequency.
"We view the totality of the data in the NAUTILUS study as a meaningful catalyst that adds to the growing body of evidence and momentum in our business," said Joel Becker, Chief Executive Officer. "With a strong base business growing over 20% year over year, we remain confident in our long-term growth strategy and excited by the opportunity ahead."
Technology Platform Advantages
The RNS System represents the first and only commercially available, brain-responsive platform that delivers personalized, real-time treatment at the seizure source. The preliminary data illustrates the system's ability to individualize patient treatment through programming over time, particularly valuable in the challenging epilepsy syndrome studied in this novel device trial design.
The company reaffirmed its previously issued full-year 2025 financial guidance following the announcement of these results.
