Restarting Triple Therapy With Robust Monitoring for Adverse Events (RETRIAL)

Inclusion Criteria:

RETRIAL-Mental Health:

* PWCF age 6 years and up (if age is \< 12 years old, the PWCF's caregiver will complete daily diaries and surveys; see "Caregiver Participant Inclusion Criteria" below)
* Eligible for VTD and intending to take it
* Experienced new or worsening mental health symptoms after initiating ETI, which led to one of the following changes in treatment to currently taking:

  1. No modulators
  2. A modulator other than ETI
  3. A flipped dose of ETI
  4. A reduced dose of ETI
* Willing to delay first VTD dose for short period of time to complete the Baseline assessments
* Has access to a smart device (phone, tablet, etc.) capable of receiving messages with survey links
* Is English-speaking.

RETRIAL-LIVER:

* A person with CF age 6 years and up
* Eligible for VTD and intending to take it
* Experienced drug-induced liver injury (as defined by local care team) after initiating ETI, which led to one of the following changes in treatment to currently taking:

  1. no modulators; or
  2. a modulator other than ETI; or
  3. a reduced or altered dose of ETI;
* Willing to delay first VTD dose for short period of time to complete the Baseline assessments
* Has access to a smart device (phone, tablet, etc.) capable of receiving messages with survey links
* Is English-speaking.

Exclusion Criteria:

RETRIAL-Mental Health:

* Cannot access VTD
* Currently, or prior history of, taking VTD
* Unable or unwilling to follow protocol
* If \<12 years old, having another \<12-year-old person in the same household consented into the study
* Is actively listed on any transplant list, or within 3 months post-transplant surgery
* Is currently pregnant (test not required)
* Anticipated change in CF Care Centers in the next 6 months
* Any situation that, in the opinion of the Investigator, would compromise the safety of the patient or the quality of the data.

RETRIAL-LIVER:

* Cannot access VTD
* Currently, or prior history of, taking VTD
* Unable or unwilling to follow protocol
* If \<12 years old, having another \<12-year-old person in the same household consented into the study
* Any severe, decompensated liver disease (e.g. Child-Pugh, Class C)
* Is actively listed on any transplant list, or within 3 months post-transplant surgery (any organ), or history of liver transplant
* Is currently pregnant (test not required)
* Anticipated change in CF Care Centers in the next 6 months
* Any situation that, in the opinion of the Investigator, would compromise the safety of the patient or the quality of the data.

Caregiver Participant:

Inclusion Criteria:

* Is a primary, daily caregiver of a person with CF under the age of 12 enrolled in the study
* Has access to smart device (phone, tablet, etc.) capable of receiving messages with survey links
* Is able to read and complete surveys and Daily Diary in English.

Exclusion Criteria:

\- Any situation that, in the opinion of the Investigator, would compromise the safety of the patient or the quality of the data.