Study	Reason for exclusion
Kerem 2008	Participants not controlled, randomised or blinded to treatment
NCT00234663	Cross‐over trial in which each participant served as their own control for the comparison of 2 different dosing regimens of ataluren
NCT00237380	Cross‐over trial in which each participant served as their own control for the comparison of 2 different dosing regimens of ataluren
NCT00351078	Not a randomised controlled trial; participants invited to single allocation safety trial after completing a previous cross‐over trial
NCT00376428	Not a randomised controlled trial; compared single agent gentamicin in 2 different populations (individuals with stop codon mutations and in a control group without stop codon mutations)
NCT01140451	Not a randomised controlled trial; participants invited to single allocation safety trial after completing a previous randomised controlled trial
NCT02107859	Not a randomised controlled trial; participants invited to single allocation safety trial after completing a previous randomised controlled trial
NCT02456103	Not a randomised controlled trial; participants invited to single allocation safety trial after completing a previous randomised controlled trial
NCT03256799	Not a randomised controlled trial; participants invited to single allocation of ivacaftor in combination with ataluren
NCT03256968	Not a randomised controlled trial; 1 participant allocated to treatment with ivacaftor in combination with ataluren
NCT03624101	Not a randomised controlled trial; single group assignment
NCT03670472	Laboratory‐based case‐control study
NCT04126473	Not a randomised controlled trial; participants with cystic fibrosis and at least 1 G542X allele or phenotypically similar nonsense allele invited to single allocation of multiple dose levels of ELX‐02 (a eukaryotic ribosomal‐selective glycoside) with and without ivacaftor
NCT04135495	Not a randomised controlled trial; phase II dose escalation study
Pradal 2002	Cross‐over trial and data from first treatment arm not presented independently; data requested, but no response to date
Romano 2000	Controlled clinical trial: participants were not randomised or blinded to treatment. Controls stated to be participants homozygous for deltaF508 mutations
Sermet‐Gaudelus 2010	Cross‐over trial in which each participant served as their own control for the comparison of 2 different dosing regimes of ataluren
Wilschanski 2003b	Cross‐over trial in which each participant served as their own control. Reported on mechanism of action of the intervention (nasal potential difference and immunofluorescence microscopy of primary human airway cells); this was not relevant to the present review, which is looking at clinical benefit