CFTR modulator

Ivacaftor

Not a drug for cystic fibrosis — a drug for particular CFTR variants. Two people with the same diagnosis get opposite answers depending on which change they carry, which is the whole argument of this site in one prescription.

What this drug connects to

The genes involved

CFTR

Cystic Fibrosis →

Ivacaftor is prescribed on the basis of which CFTR variant a person carries rather than on the diagnosis of cystic fibrosis, which makes it one of the clearest examples in medicine of genotype-directed treatment. It is a potentiator: it holds open a CFTR channel that has reached the cell surface but opens poorly. CPIC recommends it for people carrying at least one gating variant, of which G551D is the archetype, and specifically notes that it is not effective in people homozygous for F508del alone — that protein never reaches the surface, so there is nothing there for a potentiator to act on. The combination therapies developed since pair a corrector with the potentiator to address exactly that gap. Treatment is decided in a specialist clinic on confirmed clinical genotyping, and nothing here should be read as a reason to start, stop or change any medicine.

Whose work this rests on

Every guideline above was written by people. Named here because they are contributors to this page in the same sense anybody else on this site is.

Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines for ivacaftor therapy in the context of CFTR genotype

Clancy JP, Johnson SG, Yee SW, McDonagh EM, Caudle KE, Klein TE, Cannavo M, Giacomini KM

Clinical Pharmacogenetics Implementation Consortium

Clinical pharmacology and therapeutics · 2014 · PMID 24598717

Variants MyGeneLog reports for these genes

These are the positions in your own file that carry the genes above. Not every gene in a guideline is one we report — where that is the case the gene appears above without a variant here, and the note says so.

Cystic fibrosis (F508del)

CFTR · rs113993960

Cystic fibrosis (G551D, a gating variant)

CFTR · rs75527207

This page is educational and contains no dosing information. Where a clinical guideline covers one of these gene-drug pairs it is written for prescribers and works through validated algorithms alongside clinical monitoring. Nothing here is a reason to start, stop, or change a medication — that conversation belongs with the clinician or pharmacist managing your treatment.