Novel Therapeutic Approaches for Treatment of CF Patients With W1282X Premature Termination Codon Mutations

Based on previous clinical findings, the investigator hypothesize that ivacaftor will have synergistic effects with drugs that facilitate truncated but partially active W1282X CFTR protein processing (tezacaftor) in patients with W1282X CFTR. In the current study, the investigators propose to directly test the efficacy of tezacaftor/ivacaftor (TEZ/IVA) and Trikafta for W1282X CFTR therapy in the clinic in comparison to ivacaftor alone.

Study Overview

• Status: Terminated
• Conditions: Cystic Fibrosis
• Intervention / Treatment: Drug: Symdeko; Drug: Ivacaftor and Symdeko

Detailed Description

Approximately 11% of CF patients have premature termination codons (PTC), causing truncated CFTR with little to no function. No approved therapies exist for patients with PTC mutations including W1282X, a unique mutation exhibiting partial CFTR activity even in its truncated form. CFTR modulators alone enhanced CFTR function in patient cells from W1282X/G542X CFTR. Several published studies have shown CFTR modulators alone and/or in combination with readthrough (RT) agents benefit W1282X CFTR. Clinical studies further support an aspect of this notion, where two W1282X patients showed beneficial effect to Ivacaftor treatment.

• Study Type: Interventional
• Enrollment (Actual): 1
• Phase: Phase 4

Contacts and Locations

Study Locations

• United States
  • Alabama
    • Birmingham, Alabama, United States, 35233
      • University of Alabama at Birmingham

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 14 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Evidence of signed and dated informed consent/assent document(s) indicating that the subject (and/or his parent/legal guardian) has been informed of all pertinent aspects of the trial

  • Age ≥ 18 yrs
  • Body weight ≥ 16 kg
  • Diagnosis of CF and documentation of the presence of a nonsense mutation of the CFTR gene, as determined by historical genotyping
  • Ability to perform a valid, reproducible spirometry with demonstration of FEV1 ≥ 30% and ≤ 90% of predicted for age, gender, and height
  • In subjects who are sexually active, willingness to abstain from sexual intercourse or employ a barrier or medical method of contraception during the study drug administration
  • Willingness and ability to comply with all study procedures and assessments

Exclusion Criteria:

• Any change (initiation, change in type of drug, dose modification, schedule modification, interruption, discontinuation, or re-initiation) in a chronic treatment/prophylaxis regimen for CF or for CF-related conditions within 2 weeks prior to screening
• Ongoing participation in any other therapeutic clinical trial
• Evidence of pulmonary exacerbation or acute upper or lower respiratory tract infection (including viral illnesses) within 2 weeks prior to screening
• History of solid organ or hematological transplantation; positive hepatitis B surface antigen test; hepatitis C antibody test; or human immunodecifiency
• Major complication of lung disease (including massive hemoptysis, pneumothorax, or pleural effusion) within 4 weeks prior to screening
• Pregnancy or breast-feeding
• Current smoker or a smoking history of ≥ 10 pack-years (number of cigarette packs/day x number of years smoked)
• Prior or ongoing medical condition (eg, renal failure, alcoholism, drug abuse, psychiatric condition), medical history, physical findings, ECG findings, or laboratory abnormality that, in the investigator's opinion, could adversely affect the safety of the subject, makes it unlikely that the course of treatment or follow-up would be completed, or could impair the assessment of study results

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Symdeko/Trikafta; If the participant currently takes Symdeko , they will take Trikafta for a 28 day period followed by Symdeko for a 28 day period. This cycle will be continued for 168 days	Drug: Ivacaftor and Symdeko; CFTR modulator
Experimental: Symdeko; If the participant is not on a current modulator, they will take Symdeko for 28 days followed by a 28 day off period. This cycle will be continued for 168 days	Drug: Symdeko; CFTR modulator

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent Change in FEV1 From Baseline	Percent change in FEV1 from Baseline and 24 weeks	24 weeks

Collaborators and Investigators

• Sponsor: University of Alabama at Birmingham

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2018
• Primary Completion (Actual): October 3, 2019
• Study Completion (Actual): October 3, 2019

Study Registration Dates

• First Submitted: August 7, 2018
• First Submitted That Met QC Criteria: August 7, 2018
• First Posted (Actual): August 9, 2018

Study Record Updates

• Last Update Posted (Actual): April 16, 2025
• Last Update Submitted That Met QC Criteria: April 11, 2025
• Last Verified: April 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Genetic Diseases, Inborn; Respiratory Tract Diseases; Digestive System Diseases; Lung Diseases; Infant, Newborn, Diseases; Pancreatic Diseases; Cystic Fibrosis; Molecular Mechanisms of Pharmacological Action; Membrane Transport Modulators; Chloride Channel Agonists; Ivacaftor
• Other Study ID Numbers: IRB-300001363

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No