Correction of Nonsense Mutations in Cystic Fibrosis

Cystic Fibrosis Clinical Trial

Official title:

Optimization of Correcting Molecules of Nonsense Mutations in Epithelial Cells of the Upper Airways of Patients With Cystic Fibrosis With Nonsense Mutations in the CFTR Gene

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT03670472
• Other study ID #: 2013_59
• Secondary ID: 2014-A01236-41
• Status: Recruiting
• Start date: February 3, 2016
• Est. completion date: January 2030

Study information

• Verified date: October 2020
• Source: University Hospital, Lille
• Contact: Anne Prévotat, MD
• Phone: 03 20 44 59 48
• Email: anne.prevotat[@]chru-lille.fr
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

The presence of a nonsense mutation leads to the rapid degradation of the carrier mRNA mutation by a mechanism called NMD (nonsense-mediated mRNA decay) [6, 13]. There are currently 3 main strategies at least for correcting nonsense mutations: exon skipping, inhibition of NMD and nonsense mutation readthrough.

In the laboratory, we developed a strategy for correcting nonsense mutations combining inhibition of NMD and activation of translecture. For this purpose, we have constructed screening systems to identify NMD-inhibiting and/or readthrough enhancers. The molecules thus identified are then tested on cell lines and in murine models carrying a nonsense mutation.

One of our goals is to select a set of molecules that can correct effectively nonsense mutations. For this we have to test these molecules on a great diversity of nonsense mutations.

This work will:

• determine if we can correct all the nonsense mutations tested with at least one of our molecules

• determine what is common within a group of mutations corrected by a given molecule

• be able to assign the parameters that make one mutation is corrected by one molecule and not or little by another.

This study will therefore improve our theoretical knowledge on the recognition of premature stop codons but also to propose therapeutic approaches for the correction of nonsense mutations of the CFTR gene in cystic fibrosis in a targeted way for a patient.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 85
• Est. completion date: January 2030
• Est. primary completion date: January 2030
• Accepts healthy volunteers: No
• Gender: All
• Age group: 8 Years and older

Eligibility

Inclusion Criteria:

• Male / female adults and minors aged 8 years and over

• Patients with cystic fibrosis and carry a nonsense mutation on the 2 alleles of the gene coding for the CFTR channel.

• Patients whose genotype of patients concerning the CFTR gene is known.

• Patients with social security

• Major patients who have given their consent

• Minor patients with parental authorization

Exclusion Criteria:

• Patients who have a mutation other than nonsense in the CFTR gene

• Patients whose CFTR gene was not sequenced on the 2 alleles

• Patients not wishing to participate in this study or persons not giving or not able to give consent.

• Pregnant or lactating women

• Patients under curatorship or guardianship

Related Conditions & MeSH terms

• Cystic Fibrosis
• Fibrosis

Intervention

Other:
• smear of nasal fossae
1 smear of nasal fossae during a usual or scheduled visit

Locations

Country	Name	City	State
France	Camsp Chu Amiens	Amiens
France	Hopital Femme Mere Enfant - Hcl - Bron	Bron
France	Hôpital Calmette,CHU	Lille
France	Aphm Hopital La Timone - Marseille	Marseille
France	Chu Montpellier	Montpellier
France	Cmp Enfants Aphp Robert Debre - Paris	Paris
France	Hu Paris Centre Site Cochin Aphp - Paris 14	Paris
France	Hopitaux Universitaires de Strasbour	Strasbourg

Sponsors (2)

Lead Sponsor	Collaborator
University Hospital, Lille	Vaincre la Mucoviscidose

Country where clinical trial is conducted

France, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Transport of iodide ions through the CEVAS membrane	Patient cells with be cultured in BEGM (Lonza) medium and incubated with corrector of nonsense mutations for 20 hours and with a fluorescent molecule called SPQ (for 6-methoxy-N-3'-sulfopropylquinolinium). Iodine can bind SPQ and will quench the SPQ fluorescence. Nitrates bind SPQ without quenching SPQ fluorescence. By placing patient cells first into an iodine-rich medium to quench the SPQ fluorescence and second into a nitrate-rich medium, we will be able to measure the level of functional CFTR protein present in these cells by measuring the re-apparition of fluorescence using fluorimeter. Indeed, nitrate will be able to replace iodine on SPQ without quenching SPQ fluorescence only if iodine exits cells through CFTR channels. This assay allows determining whether a corrector of nonsense mutation is able to lead to the synthesis of functional CFTR protein	less than 48hrs after the collect.
Secondary	Immortalization of patient cells	Immortalization of patient cells will be attempted by transfection of construct expressing the origin-of-replication defective SV40 as described in Gruenert et al.,2004	an average 12 months
Secondary	Expression of the CFTR gene at the mRNA and protein level		less than 1 week.