Vertex 661 (Tezacaftor) Studies (Phase 3)

Study ID number: VX14-661-106  
Official Title: A Phase 3, Randomized, Double Blind, Placebo Controlled, Parallel Group Study to Evaluate the Efficacy and Safety of VX-661 in Combination With Ivacaftor in Subjects Aged 12 Years and Older With Cystic Fibrosis, Homozygous for the F508del CFTR Mutation
Therapeutic Category: CFTR Modulator

Source: ClinicalTrials. gov:  https://clinicaltrials.gov/ct2/show/NCT02347657

Publications related to the study:

https://www.ncbi.nlm.nih.gov/pubmed/29099344?dopt=Abstract

AND 

Study ID number: VX14-661-108  
Official Title: A Phase 3, Randomized, Double-Blind, Placebo-Controlled, Crossover Study to Evaluate the Efficacy and Safety of Ivacaftor and VX-661 in Combination With Ivacaftor in Subjects Aged 12 Years and Older With Cystic Fibrosis, Heterozygous for the F508del-CFTR Mutation, and a Second Allele With a CFTR Mutation Predicted to Have Residual Function
Therapeutic Category: CFTR Modulator

Source: ClinicalTrials. gov:  https://clinicaltrials.gov/ct2/show/NCT02392234

Publications related to the study:

https://www.ncbi.nlm.nih.gov/pubmed/29099333?dopt=Abstract

VX-661 (Lumacaftor) and VX-770 (Ivacaftor) are two different but complementary drugs that may help correct some of the irregularities or deformities that the gene mutation causes. VX-661 and VX-770 were being studied together to see if they can help decrease some of the effects caused by CF. They are designed to help the mutated chloride channel work more effectively which could alleviate the cycle of mucus plugging, infection, and inflammation in the lungs caused by CF.

This was a Phase 3 study to learn about safety/tolerability and effects of VX-661 when given in combination with VX-770 to subjects with CF who are homozygous for the deltaF508 mutation (have 2 copies of the deltaF508 mutation) and heterozygous for the delta F508 mutation with a residual function mutation (have at least 1 copy of deltaF508 and 1 copy of a residual function mutation) . VX-661 and VX-770 were investigated in how they may change your lung function (FEV1), weight, quality of life, and frequency of pulmonary exacerbations (lung flareups), etc over a 6 month treatment period.  

The studies have completed and proceeded to an open label extension study (where all eligible participants to enroll were given drug)

The drug was eventually approved for use on CF patients with delta F508 homozygous & those who have at least one mutation in the CF gene that is responsive to treatment February 2018 in the United States first. It was approved in Canada on June 2019. It is currently on the market as Symdeko.