Safety and Pharmacokinetic Study of Lumacaftor/Ivacaftor in Participants 1 to Less Than 2 Years of Age With Cystic Fibrosis, Homozygous for F508del

Study Overview
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Brief Summary
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This study will evaluate the safety and pharmacokinetics (PK) of lumacaftor (LUM) and ivacaftor (IVA) in participants 1 to less than 2 years of age with cystic fibrosis (CF), homozygous for F508del (F/F).

Official Title
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A Phase 3, 2-part, Open-label Study to Evaluate the Safety and Pharmacokinetics of Lumacaftor/Ivacaftor in Subjects 1 to Less Than 2 Years of Age With Cystic Fibrosis, Homozygous for F508del

Conditions
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Cystic Fibrosis

Intervention / Treatment
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* Drug: LUM
* Drug: IVA


Participation Criteria
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Eligibility Criteria
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Key Inclusion Criteria: Participants will be 1 to less than 2 years of age on day 1 of the relevant part of the study Homozygous for F508del (F/F) Key Exclusion Criteria: Any clinically significant laboratory abnormalities at the screening visit that would interfere with the study assessments or pose an undue risk for the participants Solid organ or hematological transplantation Other protocol defined Inclusion/Exclusion criteria may apply.

Ages Eligible for Study
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Minimum Age: 12 Months
Maximum Age: 23 Months

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

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: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Part A: LUM/IVA<br>Participants weighing 7 to less than (<)10 kilograms (kg) at screening received LUM 75 milligrams (mg)/IVA 94 mg fixed-dose combination (FDC) every 12 hours (q12h) and those weighing 10 to <14 kg at screening received LUM 100 mg/IVA 125 mg q12h for 15 days. Participants weighing greater than or equal to (>=)14 kg at screening received LUM 150 mg/IVA 188 mg FDC q12h for 15 days. | Drug: LUM<br>* Fixed Dose Combination (FDC) granules (LUM/IVA).<br>* Other names: VX-809;Drug: IVA<br>* FDC granules (LUM/IVA).<br>* Other names: VX-770;|
| Experimental: Part B: LUM/IVA<br>Participants weighing 7 to <9 kg at screening received LUM 75 mg/IVA 94 mg FDC q12h and those weighing 9 to <14 kg received LUM 100 mg/IVA 125 mg q12h for 24 weeks. Participants weighing >=14 kg at screening received LUM 150 mg/IVA 188 mg FDC q12h for 24 weeks. Doses were adjusted upwards for changes in weight. | Drug: LUM<br>* Fixed Dose Combination (FDC) granules (LUM/IVA).<br>* Other names: VX-809;Drug: IVA<br>* FDC granules (LUM/IVA).<br>* Other names: VX-770;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Part A: Observed Plasma Concentrations From 3-4 Hours (C3-4hr) of LUM and IVA |  | Day 1 and Day 15 | 
| Part A: Observed Pre-dose Plasma Concentration (Ctrough) of LUM and IVA |  | Pre-dose at Day 8 and Day 15 | 
| Part B : Safety and Tolerability as Assessed by Number of Participants With Treatment-Emergent Adverse Events (TEAEs) and Serious Adverse Events (SAEs) |  | From Day 1 up to Week 26 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Part A: Safety and Tolerability as Assessed by Number of Participants With Treatment-Emergent Adverse Events (TEAEs) and Serious Adverse Events (SAEs) |  | From Day 1 up to Day 25 | 
| Part A: Observed Pre-dose Plasma Concentration (Ctrough) of LUM and IVA and Their Respective Metabolites (M28-LUM, M1-IVA and M6-IVA) |  | Pre-dose at Day 8 and Day 15 | 
| Part B: Absolute Change in Sweat Chloride |  | From Baseline at Week 24 | 
| Part B: Observed Pre-dose Plasma Concentration (Ctrough) of LUM and IVA and Their Respective Metabolites (M28-LUM, M1-IVA and M6-IVA) |  | Pre-dose at Day 15, Week 4, Week 12 and Week 24 |