A Drug-drug Interaction Study With Risdiplam Multiple Dose and Midazolam in Healthy Participants

Study Overview
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Brief Summary
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This will be a Phase I, 2-part, open-label, non-randomized study to investigate the safety, tolerability, and pharmacokinetics (PK) of a multiple-dosing regimen of risdiplam (Part 1) and the effect of risdiplam on the PK of midazolam (Part 2) following oral administration in healthy adult male and female participants.

Official Title
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A Phase I, 2-Part, Open-Label Study to Investigate the Safety, Tolerability, and Pharmacokinetics of Multiple Doses of Risdiplam and the Effect of Risdiplam on the Pharmacokinetics of Midazolam Following Oral Administration in Healthy Participants

Conditions
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Spinal Muscular Atrophy

Intervention / Treatment
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* Drug: Risdiplam
* Drug: Midazolam


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy participants as defined by the Investigator A body mass index (BMI) of 18.0 to 32.0 kg/m2 Use of adequate contraception methods during the treatment period and until 4 months after last study drug administration. Males must refrain from donating sperm during this same period Willingness and ability to complete all aspects of the study Exclusion Criteria: Concomitant disease or condition that could interfere with, or treatment of which might interfere with, the conduct of the study History or evidence of any medical condition potentially altering the absorption, metabolism, or elimination of drugs Surgical history of the GI tract affecting gastric motility or altering the GI tract History or presence of clinically significant ECG abnormalities or cardiovascular disease History of malignancy in the past 5 years Positive result on human immunodeficiency virus (HIV)-1, HIV-2, hepatitis B virus, or hepatitis C virus Donation of blood or blood products for transfusion Participation in an investigational drug medicinal product or medical device study within 90 days prior to Screening Any clinically significant history of hypersensitivity or allergic reactions History of hypersensitivity to midazolam or any other benzodiazepine or its formulation ingredients For Part 2 participants: - History of acute angle glaucoma

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Sequential Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Part 1<br>Participants will receive a dose of 5 milligram (mg) risdiplam once daily (QD) for 14 consecutive days | Drug: Risdiplam<br>* Part 1: a dose of 5 milligram (mg) risdiplam QD ; Part 2: precise dose will be based on Part 1 results<br>|
| Experimental: Part 2<br>All study participants will receive a single oral dose of 2 mg midazolam on Day 1. On Day 3, the 14-day QD treatment period with risdiplam will begin. The precise dose will be based on the results of Part 1, with single dose administration of 2 mg midazolam again on Day 15 (1 hour after the thirteenth dose of risdiplam) | Drug: Risdiplam<br>* Part 1: a dose of 5 milligram (mg) risdiplam QD ; Part 2: precise dose will be based on Part 1 results<br>Drug: Midazolam<br>* single dose administration of 2 mg midazolam<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Part 2: Area Under the Concentration-Time Curve From Time Zero Extrapolated to Infinity (AUCinf) of Midazolam Alone and in Combination With Risdiplam | In Part 2 of the study, all study participants received a single oral dose of 2 mg midazolam on Day 1. On Day 3, the 14-day once daily (QD) treatment period with risdiplam began, with single dose administration of 2 mg midazolam again on Day 15 (1 hour after the thirteenth dose of risdiplam). The following treatment sequence was used in Part 2 of the study: Day 1: 2 mg midazolam; Days 3 to 14: 8 mg risdiplam QD; Day 15: 2 mg midazolam and 8 mg risdiplam QD; Day 16: 8 mg risdiplam QD. Blood samples for pharmacokinetic (PK) analysis were taken at defined timepoints on Day 1 for midazolam administered alone and on Day 15 for midazolam administered in combination with risdiplam. | Day 1 and Day 15: Predose, 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, and 24 hours postdose | 
| Part 2: Area Under the Plasma Concentration-Time Curve From Time Zero to the Time of Last Quantifiable Concentration (AUClast) of Midazolam Alone and in Combination With Risdiplam | In Part 2 of the study, all study participants received a single oral dose of 2 mg midazolam on Day 1. On Day 3, the 14-day once daily (QD) treatment period with risdiplam began, with single dose administration of 2 mg midazolam again on Day 15 (1 hour after the thirteenth dose of risdiplam). The following treatment sequence was used in Part 2 of the study: Day 1: 2 mg midazolam; Days 3 to 14: 8 mg risdiplam QD; Day 15: 2 mg midazolam and 8 mg risdiplam QD; Day 16: 8 mg risdiplam QD. Blood samples for PK analysis were taken at defined timepoints on Day 1 for midazolam administered alone and on Day 15 for midazolam administered in combination with risdiplam. | Day 1 and Day 15: Predose, 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, and 24 hours postdose | 
| Part 2: Maximum Observed Plasma Concentration (Cmax) of Midazolam Alone and in Combination With Risdiplam | In Part 2 of the study, all study participants received a single oral dose of 2 mg midazolam on Day 1. On Day 3, the 14-day once daily (QD) treatment period with risdiplam began, with single dose administration of 2 mg midazolam again on Day 15 (1 hour after the thirteenth dose of risdiplam). The following treatment sequence was used in Part 2 of the study: Day 1: 2 mg midazolam; Days 3 to 14: 8 mg risdiplam QD; Day 15: 2 mg midazolam and 8 mg risdiplam QD; Day 16: 8 mg risdiplam QD. Blood samples for PK analysis were taken at defined timepoints on Day 1 for midazolam administered alone and on Day 15 for midazolam administered in combination with risdiplam. | Day 1 and Day 15: Predose, 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, and 24 hours postdose | 
| Part 2: AUCinf of Midazolam Metabolite (1-Hydroxy Midazolam) Alone and in Combination With Risdiplam | In Part 2 of the study, all study participants received a single oral dose of 2 mg midazolam on Day 1. On Day 3, the 14-day once daily (QD) treatment period with risdiplam began, with single dose administration of 2 mg midazolam again on Day 15 (1 hour after the thirteenth dose of risdiplam). The following treatment sequence was used in Part 2 of the study: Day 1: 2 mg midazolam; Days 3 to 14: 8 mg risdiplam QD; Day 15: 2 mg midazolam and 8 mg risdiplam QD; Day 16: 8 mg risdiplam QD. Blood samples for PK analysis were taken at defined timepoints on Day 1 for midazolam administered alone and on Day 15 for midazolam administered in combination with risdiplam. | Day 1 and Day 15: Predose, 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, and 24 hours postdose | 
| Part 2: AUClast of Midazolam Metabolite (1-Hydroxy Midazolam) Alone and in Combination With Risdiplam | In Part 2 of the study, all study participants received a single oral dose of 2 mg midazolam on Day 1. On Day 3, the 14-day once daily (QD) treatment period with risdiplam began, with single dose administration of 2 mg midazolam again on Day 15 (1 hour after the thirteenth dose of risdiplam). The following treatment sequence was used in Part 2 of the study: Day 1: 2 mg midazolam; Days 3 to 14: 8 mg risdiplam QD; Day 15: 2 mg midazolam and 8 mg risdiplam QD; Day 16: 8 mg risdiplam QD. Blood samples for PK analysis were taken at defined timepoints on Day 1 for midazolam administered alone and on Day 15 for midazolam administered in combination with risdiplam. | Day 1 and Day 15: Predose, 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, and 24 hours postdose | 
| Part 2: Cmax of Midazolam Metabolite (1-Hydroxy Midazolam) Alone and in Combination With Risdiplam | In Part 2 of the study, all study participants received a single oral dose of 2 mg midazolam on Day 1. On Day 3, the 14-day once daily (QD) treatment period with risdiplam began, with single dose administration of 2 mg midazolam again on Day 15 (1 hour after the thirteenth dose of risdiplam). The following treatment sequence was used in Part 2 of the study: Day 1: 2 mg midazolam; Days 3 to 14: 8 mg risdiplam QD; Day 15: 2 mg midazolam and 8 mg risdiplam QD; Day 16: 8 mg risdiplam QD. Blood samples for PK analysis were taken at defined timepoints on Day 1 for midazolam administered alone and on Day 15 for midazolam administered in combination with risdiplam. | Day 1 and Day 15: Predose, 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, and 24 hours postdose | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Part 1: Area Under the Plasma Concentration-Time Curve From Time Zero to the End of the Dosing Interval (AUCtau) of Risdiplam and Its Metabolite (M1) Following Multiple Oral Doses | In Part 1 of the study, participants received a single oral dose of 5 mg risdiplam once daily (QD) for 14 consecutive days. Blood samples for risdiplam and its metabolite were taken at defined timepoints on Day 1 and on Day 14 for the PK analysis. | Day 1: Predose, 0.5, 1, 2, 3, 4, 5, 6, 8, 10, and 12 hours postdose; Day 2 to Day 13: Predose; Day 14: Predose, 0.5, 1, 2, 3, 4, 5, 6, 8, 10, 12, 24, 36, 48, 96, and 144 hours postdose | 
| Part 1: AUClast of Risdiplam and M1 Risdiplam Following Multiple Oral Doses | In Part 1 of the study, participants received a single oral dose of 5 mg risdiplam once daily (QD) for 14 consecutive days. Blood samples of risdiplam and its metabolite were taken at defined timepoints on Day 1 and on Day 14 for the PK analysis. | Day 1: Predose, 0.5, 1, 2, 3, 4, 5, 6, 8, 10, and 12 hours postdose; Day 2 to Day 13: Predose; Day 14: Predose, 0.5, 1, 2, 3, 4, 5, 6, 8, 10, 12, 24, 36, 48, 96, and 144 hours postdose | 
| Part 1: Cmax of Risdiplam and M1 Risdiplam Following Multiple Oral Doses | In Part 1 of the study, participants received a single oral dose of 5 mg risdiplam once daily (QD) for 14 consecutive days. Blood samples of risdiplam and its metabolite were taken at defined timepoints on Day 1 and on Day 14 for the PK analysis. | Day 1: Predose, 0.5, 1, 2, 3, 4, 5, 6, 8, 10, and 12 hours postdose; Day 2 to Day 13: Predose; Day 14: Predose, 0.5, 1, 2, 3, 4, 5, 6, 8, 10, 12, 24, 36, 48, 96, and 144 hours postdose | 
| Part 2: AUCtau of Risdiplam and M1 Risdiplam Following Multiple Oral Doses | In Part 2 of the study, all study participants received a single oral dose of 2 mg midazolam on Day 1. On Day 3, the 14-day once daily (QD) treatment period with risdiplam began, with single dose administration of 2 mg midazolam again on Day 15 (1 hour after the thirteenth dose of risdiplam). The following treatment sequence was used in Part 2 of the study: Day 1: 2 mg midazolam; Days 3 to 14: 8 mg risdiplam QD; Day 15: 2 mg midazolam and 8 mg risdiplam QD; Day 16: 8 mg risdiplam QD. | Day 3: Predose, 0.5, 1, 2, 3, 4, 5, 6, 8, 10, and 12 hours postdose; Day 4 to Day 15: Predose; Day 16: Predose, 0.5, 1, 2, 3, 4, 5, 6, 8, 10, 12, 24, 36, 48, 96, and 144 hours postdose | 
| Part 2: AUClast of Risdiplam and M1 Risdiplam Following Multiple Oral Doses | In Part 2 of the study, all study participants received a single oral dose of 2 mg midazolam on Day 1. On Day 3, the 14-day once daily (QD) treatment period with risdiplam began, with single dose administration of 2 mg midazolam again on Day 15 (1 hour after the thirteenth dose of risdiplam). The following treatment sequence was used in Part 2 of the study: Day 1: 2 mg midazolam; Days 3 to 14: 8 mg risdiplam QD; Day 15: 2 mg midazolam and 8 mg risdiplam QD; Day 16: 8 mg risdiplam QD. | Day 3: Predose, 0.5, 1, 2, 3, 4, 5, 6, 8, 10, and 12 hours postdose; Day 4 to Day 15: Predose; Day 16: Predose, 0.5, 1, 2, 3, 4, 5, 6, 8, 10, 12, 24, 36, 48, 96, and 144 hours postdose | 
| Part 2: Cmax of Risdiplam and M1 Risdiplam Following Multiple Oral Doses | In Part 2 of the study, all study participants received a single oral dose of 2 mg midazolam on Day 1. On Day 3, the 14-day once daily (QD) treatment period with risdiplam began, with single dose administration of 2 mg midazolam again on Day 15 (1 hour after the thirteenth dose of risdiplam). The following treatment sequence was used in Part 2 of the study: Day 1: 2 mg midazolam; Days 3 to 14: 8 mg risdiplam QD; Day 15: 2 mg midazolam and 8 mg risdiplam QD; Day 16: 8 mg risdiplam QD. | Day 3: Predose, 0.5, 1, 2, 3, 4, 5, 6, 8, 10, and 12 hours postdose; Day 4 to Day 15: Predose; Day 16: Predose, 0.5, 1, 2, 3, 4, 5, 6, 8, 10, 12, 24, 36, 48, 96, and 144 hours postdose | 
| Part 2: Percentage of Participants With Adverse Events After Midazolam Administration Alone and in Combination With Risdiplam | An adverse event is any untoward medical occurrence in a participant administered a pharmaceutical product and which does not necessarily have to have a causal relationship with the treatment. An adverse event can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding, for example), symptom, or disease temporally associated with the use of a pharmaceutical product, whether or not considered related to the pharmaceutical product. Preexisting conditions which worsen during a study are also considered as adverse events. | Day 1 to Day 20 and up to 10+/-2 Days Post Final Dose or Early Termination | 
| Part 1 and Part 2: Percentage of Participants With Adverse Events After Administration of Multiple Doses of Risdiplam | An adverse event is any untoward medical occurrence in a participant administered a pharmaceutical product and which does not necessarily have to have a causal relationship with the treatment. An adverse event can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding, for example), symptom, or disease temporally associated with the use of a pharmaceutical product, whether or not considered related to the pharmaceutical product. Preexisting conditions which worsen during a study are also considered as adverse events. | Day 1 to Day 20 and up to 10+/-2 Days Post Final Dose or Early Termination |