Rapport Therapeutics Prepares to Report Phase IIa Epilepsy Trial Results for RAP-219

Rapport Therapeutics查看公司主页 Inc. (RAPP) is set to unveil topline results from its Phase IIa trial of RAP-219查看药品详情 in patients with drug-resistant focal onset seizures (搜索)搜索该疾病 during a conference call scheduled for 8:00 AM ET on September 8, 2025. The announcement represents a critical inflection point for the clinical-stage biopharmaceutical company's lead neurological program.

Addressing Unmet Medical Need in Epilepsy

Despite over 20 FDA-approved antiseizure medications currently available, 30% to 40% of epilepsy (搜索)搜索该疾病 patients remain drug-resistant, highlighting a significant unmet medical need. Focal seizures, which start in one part of the brain while patients remain fully aware and alert, represent the most common type of seizures in people with epilepsy.

The Phase IIa proof-of-concept trial, now fully enrolled, was designed with input from leading epilepsy (搜索)搜索该疾病 experts and utilizes intracranial electroencephalography (iEEG) data from the RNS System to assess RAP-219查看药品详情's potential effect on long episodes (LEs), an objective biomarker shown to correlate with clinical seizures.

Trial Design and Patient Population

Preliminary baseline characteristics from the first 14 enrolled patients indicate the trial population is representative of patients historically enrolled in registrational refractory focal epilepsy (搜索)搜索该疾病 trials. The enrolled patients had a median age of 37 years (range 20-61), with equal gender distribution (7 female/7 male). Patients experienced a median of 10 clinical seizures per 28 days during the 4-week prospective baseline period and 51 long episodes per 28 days during the 12-week baseline period.

The trial population showed high concordance between long episodes and electrographic seizures at 92% (range 71-96%), as rated by an independent reviewer. Patients had been living with their RNS implants for a median of 4.4 years and were taking a median of 3 concomitant antiseizure medications.

Primary and Secondary Endpoints

The September 2025 topline results will include comprehensive primary and secondary endpoint analyses. The primary endpoint analysis will evaluate the proportion of patients achieving a 30% or greater reduction in long episodes during the 8-week treatment period compared with the 12-week baseline period, along with the median percent change in long episode frequency.

Key secondary endpoint analysis will assess the proportion of patients achieving a 50% or greater reduction in clinical seizures during the 8-week treatment period compared with the 4-week prospective baseline, plus the median percent change in clinical seizure frequency. The results will also include data on the incidence and severity of treatment-emergent adverse events.

Precision Neuroscience Approach

RAP-219查看药品详情 represents a novel approach to neurological drug development as an AMPA receptor (搜索)搜索该靶点 negative allosteric modulator designed to achieve neuroanatomical specificity through selective targeting of TARP γ8 (搜索)搜索该靶点, a receptor associated protein. While AMPA receptors are distributed widely throughout the central nervous system, TARP γ8 is expressed only in discrete regions, including the hippocampus and neocortex where focal seizures often originate.

Importantly, TARP γ8 (搜索)搜索该靶点 has minimal expression in the hindbrain, where drug effects are often associated with intolerable adverse events. This precision targeting approach potentially allows RAP-219查看药品详情 to provide therapeutic benefits while avoiding the tolerability issues common with traditional neuroscience medications.

Strong Safety Profile from Phase 1 Studies

Consolidated safety data from four completed Phase 1 trials involving 100 healthy volunteers support RAP-219查看药品详情's differentiated tolerability profile. Across three multiple dose trials (n=64), all treatment-emergent adverse events were Grade 1 or 2, with no serious adverse events reported. The company observed no clinically significant laboratory, vital signs, or electrocardiogram abnormalities.

The most common treatment-emergent adverse events included headache (n=12), dry mouth (n=5), brain fog (n=5), and fatigue (n=5). These adverse events occurred early in dosing and resolved without further action, with only three discontinuations across all studies.

Broader Pipeline Potential

Due to the role of AMPA biology in various neurological disorders and the selective targeting of TARP γ8 (搜索)搜索该靶点, Rapport believes RAP-219查看药品详情 has "pipeline-in-a-product" potential. The company is evaluating the compound as a treatment for focal epilepsy (搜索)搜索该疾病, bipolar disorder (搜索)搜索该疾病, and peripheral neuropathic pain.

Upcoming catalysts include the initiation of a RAP-219查看药品详情 Phase 2a trial in bipolar mania in Q3 2025, with topline results expected in the first half of 2027. The company also plans to provide updates on its diabetic peripheral neuropathic pain (搜索)搜索该疾病 program in the second half of 2025.

Financial Position

As of March 31, 2025, Rapport reported $285.4 million in cash, cash equivalents, and short-term investments, excluding restricted cash. These funds are expected to support operations through the end of 2026, providing financial runway to advance multiple clinical programs.

Abraham N. Ceesay, Chief Executive Officer of Rapport Therapeutics查看公司主页, stated: "This will mark a major milestone for our lead program and an opportunity to demonstrate the strength of our precision neuroscience approach. We're excited to share additional details about the trial ahead of the readout and honored to be joined by Dr. French, principal investigator of our RAP-219查看药品详情 epilepsy (搜索)搜索该疾病 trial."