Study Evaluating the Efficacy and Safety of RAP-219 in Adult Participants With Focal Seizures

Inclusion Criteria: 1. Age 18 - 75 2. BMI 18-45 kg/m2 3. Diagnosis of focal epilepsy for ≥24 months prior to Visit 1 4. Report from at least 1 brain MRI or CT scan and 1 EEG study, each completed within 10 years prior to Visit 1, consistent with focal epilepsy diagnosis 5. Concomitant use of between 1 and 3, inclusive, antiseizure medication(s) ASM(s) as maintenance, not including rescue or pro re nata (PRN) ASMs 6. Ability to keep accurate daily focal seizure records using an e-diary Exclusion Criteria: 1. Known hypersensitivity or prior exposure to RAP-219. 2. Unstable or uncontrolled serious medical, neurologic (other than focal epilepsy), or psychiatric condition that is ongoing or considered likely to recur 3. Anticipated need for surgery during the study period 4. Medical history of any of the following: 1. generalized epilepsy 2. focal preserved consciousness without observable manifestations (also known as focal aware nonmotor) as the participant's only seizure type 3. psychogenic nonepileptic seizure (PNES) 4. status epilepticus or seizure clusters (when individual seizures cannot be counted) within 12 months prior to Visit 1 (Day -56). 5. epilepsy surgery within 12 months prior to Visit 1 (Day -56). 5. Participation in another clinical study of an investigational product within 12 weeks or 5 half-lives of this other investigational product