Study: NCT04452006

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: ACT-541478 30 mg
Description: ACT-541478 will be provided in HPMC capsules for oral administration at a dose strength of 10 mg.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: ACT-541478 100 mg
Description: ACT-541478 will be provided in HPMC capsules for oral administration at a dose strength of 50 mg.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: ACT-541478 100 mg
Description: ACT-541478 will be provided in HPMC capsules for oral administration at a dose strength of 50 mg.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: ACT-541478 100 mg
Description: ACT-541478 will be provided in HPMC capsules for oral administration at a dose strength of 50 mg.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: ACT-541478 300 mg
Description: ACT-541478 will be provided in HPMC capsules for oral administration at dose strengths of 50 mg and 250 mg.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: ACT-541478 300 mg
Description: ACT-541478 will be provided in HPMC capsules for oral administration at dose strengths of 50 mg and 250 mg.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: ACT-541478 1000 mg
Description: ACT-541478 will be provided in HPMC capsules for oral administration at a dose strength of 250 mg.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: ACT-541478 high or low dose (or placebo)
Description: Cross-over design: ACT-541478 will be provided in HPMC capsules for oral administration at high or low dose strengths (to be defined after completion of Part A).

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: ACT-541478 dose E1
Description: E1 is a dose level that has been investigated and well tolerated in the adult dose level groups C1 to C3. ACT-541478 will be provided in HPMC capsules for oral administration at dose strengths of 10, 50, and 250 mg.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Matching placebo
Description: Matching placebo will be provided in HPMC capsules for oral administration.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Matching placebo
Description: Matching placebo will be provided in HPMC capsules for oral administration.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Matching placebo
Description: Matching placebo will be provided in HPMC capsules for oral administration.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Matching placebo
Description: Matching placebo will be provided in HPMC capsules for oral administration.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Matching placebo
Description: Matching placebo will be provided in HPMC capsules for oral administration.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Matching placebo
Description: Matching placebo will be provided in HPMC capsules for oral administration.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Matching placebo
Description: Matching placebo will be provided in HPMC capsules for oral administration.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Matching placebo
Description: Matching placebo will be provided in HPMC capsules for oral administration.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Matching placebo
Description: Matching placebo will be provided in HPMC capsules for oral administration.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Matching placebo
Description: Matching placebo will be provided in HPMC capsules for oral administration.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Matching placebo
Description: Matching placebo will be provided in HPMC capsules for oral administration.