A Study to Evaluate the Safety, Tolerability, Pharmacokinetics (PK), and Pharmacodynamics (PD) of Single and Multiple Oral Dose of TAK-418 in Healthy Female Participants

The drug being tested in this study is called TAK-418. This study will assess the safety,
tolerability, PK and PD of single and multiple rising doses of TAK-418 in healthy Japanese or
non-Japanese females.

The study will enroll approximately 48 participants in 6 cohorts and each cohort will have 8
participants. The study will include 2 parts: single rising dose (SRD) in Cohort 1 and
multiple rising dose (MRD) in Cohorts 2 to 6. Cohort 3 will include cerebrospinal fluid (CSF)
collection. Participants will be randomly assigned (by chance, like flipping a coin) to one
of the 6 cohorts.

This two-center trial will be conducted in the United States. The overall time to participate
in Cohort 1 of this study is approximately 105 days and 98 days in Cohort 2. Participants
will be contacted by telephone 14 days after last dose of study drug for a follow-up
assessment.

Inclusion Criteria:

1. Has a body mass index (BMI) greater than or equal to (>=) 18.5 and less than or equal
to (<=) 30.0 kilogram per square meter (kg/m^2) at the Screening Visit. (Cohorts 1 to
4 only).

2. Is a nonsmoker who has not used tobacco- or nicotine-containing products (example,
nicotine patch) for at least 6 months before administration of the first dose of trial
drug or invasive procedure.

3. The participant either is of nonchildbearing potential, OR, if of childbearing
potential, is using a highly effective method of contraception with low user
dependency during the entire duration of the study.

For Cohorts 5 and 6 (Japanese participants) only:

1. Has a BMI >=18.0 and <= 26.0 kg/m^2, at the Screening Visit.

Exclusion Criteria:

1. Has a positive test result for hepatitis B surface antigen (HBsAg), hepatitis C
antibody (HCV), or human immunodeficiency virus (HIV) antibody/antigen, at Screening.

2. Had major surgery, donated or lost 1 unit of blood (approximately 500 milliliter [mL])
within 4 weeks before the Screening Visit.

3. Has a history of alcohol consumption exceeding 2 standard drinks per day on average (1
glass is approximately equivalent to beer [354 mL/12 ounces], wine [118 mL/4 ounces],
or distilled spirits [29.5 mL/1 ounce] per day).

4. Consumes excessive amounts, defined as greater than 6 servings (1 serving is
approximately equivalent to 120 mg of caffeine) of coffee, tea, cola, energy drinks,
or other caffeinated beverages per day.

5. Has a substance abuse disorder.

6. Has risk of suicide according to the investigator's clinical judgment per
Columbia-Suicide Severity Rating Scale (C-SSRS) at Screening or has made a suicide
attempt in the 6 months before Screening.

7. Has luteinizing hormone (LH), follicle-stimulating hormone (FSH), or estradiol levels
that are clinically abnormal.

8. Has a resting heart rate outside of the range of 50 to 100 beats per minute, confirmed
on repeat testing within a maximum of 30 minutes, at the Screening Visit or Check-in
(Day -1).

For Cohort 3 only (includes CSF sample collection):

1. Has had CSF collection performed within 30 days before Check-in (Day -1).

2. Has significant vertebral deformities (scoliosis or kyphosis) that, in the opinion of
the investigator, may interfere with the lumbar puncture procedure.

3. Has a local infection at the puncture site.

4. Has thrombocytopenia or other suspected bleeding tendencies noted before the
procedure.

5. Has developed signs and symptoms of spinal radiculopathy, including lower extremity
pain and paresthesia.

6. Has any focal neurological deficit that might suggest an increase in intracranial
pressure.

7. Has any abnormal finding on ophthalmological assessment/fundoscopy indicative of
raised intracranial pressure (that is, optic disc swelling/edema; or [uncontrolled]
hypertensive retinopathy).

8. Regularly has moderate-to-severe headaches requiring analgesics.

9. Has any bleeding abnormality or history of bleeding abnormalities.

10. Has abnormal coagulation tests (prothrombin time [PT]/international normalized ratio
[INR], partial thromboplastin time [PTT]) at Screening.