The purpose of the study is to follow patients with partial onset seizures prospectively over 5 years in the real-world environment to gather data on the long-term safety and effectiveness of the RNS System at qualified CECs by qualified neurologists, epileptologists, and neurosurgeons trained on the RNS System.

NeuroPace, Inc. is sponsoring a post-approval study (PAS) of the RNS System device. The RNS System is the first FDA-approved closed loop responsive neurostimulator designed to reduce the frequency of seizures in individuals with partial onset seizures.

The RNS System Epilepsy PAS is a 5 year, non-randomized, open-label, multi-center prospective observational study. Data regarding safety and efficacy are collected at enrollment and periodically throughout the 5-year study.

The study is designed to assess the long-term safety and effectiveness of the RNS System as an adjunctive therapy in reducing the frequency of seizures in individuals 18 years of age or older with partial onset seizures who have undergone diagnostic testing that localized no more than 2 epileptogenic foci, are refractory to two or more antiepileptic medications, and currently have frequent and disabling seizures (motor partial seizures, complex partial seizures and/or secondarily generalized seizures).

Data from the RNS System Epilepsy PAS will be used to calculate long-term SAE rates, median percent change in seizure frequency (from pre-implant retrospective data), as well as other safety and effectiveness endpoints.

Inclusion Criteria:

A clinical decision to treat the patient with the RNS System in accordance with its approved indication for use has been made prior to enrollment in the study. For approved indication for use and contraindications, refer to current physician labeling and instructions for use (manuals) for the RNS System available at the NeuroPace website (www.neuropace.com).

This post-approval study also has the following additional study related inclusion criteria:

• Subject or legal guardian is able to provide appropriate consent to participate
• Subject is able to maintain a seizure diary alone or with the assistance of a competent individual
• Subject is able to attend clinic appointments in accordance with the study schedule

Exclusion Criteria:

Per clinician assessment, treatment with the RNS System is contraindicated based on current RNS System labeling. For approved indication for use and contraindications, refer to current physician labeling and instructions for use (manuals) for the RNS System available at the NeuroPace website (www.neuropace.com).

This post-approval study has the following additional study related exclusion criteria:

• Subject is participating in a therapeutic investigational drug or device study
• Subject was treated with a VNS within the last three months (90 days)
• Subject is pregnant

Individuals 18 years of age or older with partial onset seizures who have undergone diagnostic testing that localized no more than 2 epileptogenic foci, are refractory to two or more antiepileptic medications, and currently have frequent and disabling seizures.