The primary purpose of the study is to evaluate the safety, tolerability, and pharmacokinetics (PK) of E2730 of multiple ascending oral doses in healthy adult participants and to assess the differences in PK, safety, and tolerability of E2730 between healthy Japanese and non-Japanese participants following multiple doses. This study will also determine the effect of food on PK of E2730.

Inclusion Criteria:

1. Non-smoking, healthy male or female, age greater than or equal to (>=) 18 years and <55 years old at the time of informed consent. To be considered non-smokers, Participants must have discontinued smoking for at least 4 weeks before dosing
2. Japanese Participants must have been born in Japan of Japanese parents and Japanese grandparents, must have lived no more than 5 years outside of Japan, and must not have changed their life style or habits, including diet, while living outside of Japan
3. Body mass index (BMI) >=18 and <30 kilograms per meter square (kg/m^2) at Screening

Exclusion Criteria:

1. Females who are breastfeeding or pregnant at Screening or Baseline (as documented by a positive beta-human chorionic gonadotropin [β-hCG] test). A separate baseline assessment is required if a negative screening pregnancy test was obtained more than 72 hours before the first dose of study drug

2. Females of childbearing potential who:

   • Within 28 days before study entry, did not use a highly effective method of contraception, which includes any of the following:
   • Total abstinence (if it is their preferred and usual lifestyle)
   • An intrauterine device or intrauterine hormone-releasing system (IUS)
   • A contraceptive implant
   • An oral contraceptive (Participant must have been on a stable dose of the same oral contraceptive product for at least 28 days before dosing and must agree to stay on the same dose of the oral contraceptive throughout the study and for 28 days after study drug discontinuation)
   • Have a vasectomized partner with confirmed azoospermia
   • Do not agree to use a highly effective method of contraception throughout the entire study period and for 28 days after study drug discontinuation

3. Males who have not had a successful vasectomy (confirmed azoospermia) if their female partners meet the exclusion criteria above (that is, the female partners are of childbearing potential and are not willing to use a highly effective contraceptive method throughout the study period and for 5 times the half-life of the study drug plus 90 days after study drug discontinuation)

4. Clinically significant illness that requires medical treatment within 8 weeks or a clinically significant infection that requires medical treatment within 4 weeks of dosing

5. Evidence of disease that may influence the outcome of the study within 4 weeks before dosing; example, psychiatric disorders and disorders of the gastrointestinal tract, liver, kidney, respiratory system, endocrine system, hematological system, neurological system, or cardiovascular system, or participants who have a congenital abnormality in metabolism

6. Any history of gastrointestinal surgery that may affect PK profiles of E2730, example, hepatectomy, nephrectomy, and digestive organ resection

7. Any clinically abnormal symptom or organ impairment found by medical history, physical examinations, vital signs, ECG finding, or laboratory test results that require medical treatment at Screening

8. A prolonged QT interval of the ECG/Corrected QT interval (QT/QTc) (QTcF greater than [>] 450 milliseconds [ms]) demonstrated by a repeated ECG at Screening or Baseline (based on average of triplicate ECGs). A history of risk factors for torsade de pointes (example, heart failure, hypokalemia, family history of long QT Syndrome) or the use of concomitant medications that prolonged the QT/QTc interval

9. Persistent systolic BP >139 or <90 millimeter of mercury (mmHg) or diastolic BP >89 or <50 mmHg at Screening or Baseline

10. Heart rate <45 beats/minute or >100 beats/minute at Screening or Baseline

11. Any lifetime history of suicidal ideation or any lifetime history of suicidal behavior as indicated by the Columbia-Suicide Severity Rating Scale (C-SSRS) or equivalent scale or via interview with a psychiatrist

12. Any lifetime history of psychiatric disease (including but not limited to depression or other mood disorders, bipolar disorder, psychotic disorders, including schizophrenia, panic attacks, anxiety disorders ). The absence of a history of psychiatric disease should be documented by a checklist in the electronic case report form (eCRF)

13. Any current psychiatric symptoms as indicated by a standard screening tool

14. Any suicidal ideation with intent with or without a plan at Screening or within 6 months of Screening (that is, answering "Yes" to questions 4 or 5 on the Suicidal Ideation section of the C-SSRS)

15. Any lifetime suicidal behavior (per the Suicidal Behavior Section of the C-SSRS)

16. Known history of clinically significant drug allergy at Screening

17. Known history of food allergies or presently experiencing significant seasonal or perennial allergy at Screening

18. Known to be human immunodeficiency virus (HIV) positive at Screening

19. Active viral hepatitis (A, B, or C) and syphilis as demonstrated by positive serology at Screening

20. History of drug or alcohol dependency or abuse, or those who have a positive drug test at Screening or Baseline

21. Exposure within the last 14 days to an individual with confirmed or probable corona virus disease 2019 (COVID-19) or symptoms within the last 14 days that are on the most recent Centers for Disease Control and Prevention (CDC) list of COVID symptoms or any other reason to consider the participants at potential risk for an acute COVID-19 infection

22. Currently enrolled in another clinical study or used any investigational drug or device within 28 days or 5 half-lives, whichever is longer, preceding informed consent

23. Receipt of blood products within 4 weeks, or donation of blood within 8 weeks, or donation of plasma within 1 week of dosing

24. Any personal or family history of seizures (including febrile seizures) or epilepsy or episode of unexplained loss of consciousness

25. Any history of neurological or other medical conditions which in the opinion of the investigator has the potential to reduce seizure threshold (example, history of head concussion, traumatic brain injury, alcohol abuse, substance abuse, developmental abnormalities in the brain)

26. Any epileptiform discharges on resting EEG (including during hyperventilation and photo-stimulation)

Eisai's data sharing commitment and further information on how to request data can be found on our website http://eisaiclinicaltrials.com/.