Age 4 months to less than 6 months old

Study 8

The safety and tolerability of KALYDECO were evaluated in 36 children age 4 months to less than 2 years old with cystic fibrosis (CF). All the children in this study took KALYDECO.

One part of the study evaluated 6 children age 4 months to less than 6 months old.

See the results for children age 6 months to less than 1 year old and 1 year to less than 2 years old.


Mutations eligible to enroll in this study were:

G1244E, G1349D, G178R, G551D, G551S, R117H, S1251N, S1255P, S549N, S549R.


How KALYDECO was given

All children age 4 months to less than 6 months of age received 25 mg of KALYDECO oral granules.

In the clinical study, instruction was provided to give the dose of KALYDECO oral granules mixed into 1 teaspoon of an age-appropriate soft food or liquid, either orally with a syringe or with a spoon, every 12 hours along with a fat-containing food. 

Direction was given to ensure the full contents of the syringe were administered.

KALYDECO granules should not be given with a bottle.

Learn how to give your child KALYDECO oral granules.

Study results



The safety of KALYDECO, observed in this study, was similar to what was observed in KALYDECO studies in people with CF age 2 years and older.

See additional safety information.


Other study results

Sweat Chloride

Sweat chloride

For children age 4 months to less than 6 months old who took KALYDECO:
Sweat chloride decreased on average by -50.0 mmol/L at Week 24.

Sweat chloride is the amount of salt in your child’s sweat. A decrease in sweat chloride levels does not mean there will be an improvement in lung function (FEV1). 

Because no one in this study took placebo, it is not known if changes in sweat chloride were due to KALYDECO.


Study limitations

KALYDECO was approved in people age 4 months to less than 6 months old based on the efficacy shown in studies of KALYDECO in older people as well as the safety assessment in this study.

Talk to your healthcare provider to learn more about how KALYDECO was approved in this age group.

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