Based on available data, UCB has decided to stop development of padsevonil as adjunctive treatment of focal-onset seizures

The purpose of the study in Part 1, is to evaluate (under fasted conditions) the plasma pharmacokinetics (PK) of padsevonil (PSL) using 4 PSL product variants against a PSL reference tablet and in Part 2, to evaluate the PK of PSL using a PSL reference tablet under fed and fasted conditions at 200 mg and 400 mg.

Inclusion Criteria:

• Participant must be 18 to 55 years of age, inclusive, at the time of signing the informed consent form (ICF)

• Study participants must be overtly healthy as determined by medical evaluation including medical history, physical examination, laboratory tests, and cardiac monitoring

• Study participants must have a body weight of at least 50 kg for males and 45 kg for females and body mass index within the range 18 to 35 kg/m2 (inclusive)

• Study participants who are male or female:

  1. A male participant must agree to use contraception during the treatment period and for at least 7 days after the last dose of study treatment and refrain from donating sperm during this period

  2. A female participant is eligible to participate if she is not pregnant, not breastfeeding, and at least 1 of the following conditions applies:

     • Not a woman of childbearing potential (WOCBP) OR
     • A WOCBP who agrees to follow the contraceptive guidance during the treatment period and for at least 30 days (or 5 terminal half-lives) after the last dose of study medication

Exclusion Criteria:

• Study participant has any medical or psychiatric condition that, in the opinion of the Investigator, could jeopardize or would compromise the study participant's ability to participate in this study or a history of schizophrenia, or other psychotic disorder, bipolar disorder, or severe unipolar depression. The presence of potential psychiatric exclusion criteria will be determined based on the psychiatric history collected at Screening
• Study participant has a history or presence of/significant history of cardiovascular, respiratory, hepatic, renal, gastrointestinal, endocrinological, hematological, or neurological disorders capable of significantly altering the absorption, metabolism, or elimination of drugs; constituting a risk when taking the study intervention; or interfering with the interpretation of data
• Study participant has a history or present condition of respiratory or cardiovascular disorders, (eg, cardiac insufficiency, coronary heart disease, hypertension, arrhythmia, tachyarrhythmia, or myocardial infarction)
• Study participant has had lymphoma, leukemia, or any malignancy within the past 5 years except for basal cell or squamous epithelial carcinomas of the skin that have been resected with no evidence of metastatic disease for 3 years
• Study participant has used hepatic enzyme-inducing drugs (eg, glucocorticoids, phenobarbital, isoniazid, phenytoin, rifampicin, etc) within 2 months prior to the first dose of study medication. In case of uncertainty, the Medical Monitor should be consulted
• Study participant has participated in another study of an investigational study medication (and/or an investigational device) within the previous 60 days before Screening (or 5 half-lives, whichever is longer) or is currently participating in another study of an investigational study medication (and/or an investigational device)
• Study participant has made a blood donation or has had a comparable blood loss (>400 mL) within the last 3 months prior to the Screening Visit or has made plasma donation within last month prior to the Screening Visit
• Study participant smokes more than 5 cigarettes per day (or equivalent) or has done so within 6 months prior to the Screening Visit

Due to the small sample size in this trial, Individual Patient Data cannot be adequately anonymized and there is a reasonable likelihood that individual participants could be re-identified. For this reason, data from this trial cannot be shared.