Cystic FibrosisPhase 1/2RESTORE-CFNCT03375047
Study to Evaluate the Safety & Tolerability of MRT5005 Administered by Nebulization in Adults With Cystic Fibrosis
A Phase 1/2 study testing MRT5005 and Normal saline in people with Cystic Fibrosis, run by Sanofi at 16 sites in United States.
Trial summary
This Phase 1/2, first-in-human study evaluated the safety and tolerability of single and multiple escalating doses of MRT5005 administered by nebulization to the respiratory tract of adult subjects with cystic fibrosis (CF). Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Cystic Fibrosis
- What is being tested?
- MRT5005 and Normal saline
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 42 participants
- Where
- 16 sitesUnited States
- Study dates
- 10 May 2018to 15 Mar 2022
- Phase
- Phase 1/2
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Confirmed diagnosis of CF as defined by both of the following:
- Two CF disease-causing cystic fibrosis transmembrane conductance regulator (CFTR) mutations in Class I or II (genotype confirmed at the screening visit).
- Chronic sinopulmonary disease and/or gastrointestinal/nutritional abnormalities consistent with CF disease.
- Clinically stable CF disease, as judged by the investigator.
- Forced expiratory volume in 1 second (FEV1) ≥50% and ≤90% of the predicted normal for age, gender, and height at screening.
- Resting oxygen saturation ≥92% on room air (pulse oximetry).
Who cannot join
- An acute upper or lower respiratory infection, pulmonary exacerbation, or clinically significant episode of hemoptysis or change in chronic respiratory medications (including antibiotics) for CF lung disease within 28 days prior to dosing with investigational product on Day 1.
- Participants were receiving treatment with ivacaftor monotherapy (KALYDECO).
- Parts A and B only: Were receiving treatment with triple combination therapy (TRIKAFTA).
- Participants with a Class III, IV, or V CFTR gene mutation in at least 1 allele.
- Infection with highly virulent bacteria associated with accelerated decline in pulmonary function and/or decreased survival (e.g., Burkholderia cenocepacia, Burkholderia dolosa, Mycobacterium abscessus).
- Treatment with ORKAMBI or SYMDEKO was not an exclusion for this study.
Trial locations and contacts
16 sites in 1 country.
16 sites in 1 country
United States16 sites
University of Michigan
Ann Arbor, Michigan, 48109
Johns Hopkins University
Baltimore, Maryland, 21287
University of Alabama at Birmingham
Birmingham, Alabama, 35233
Northwestern University
Chicago, Illinois, 60611
University of Cincinnati
Cincinnati, Ohio, 45267
University Hospitals
Cleveland, Ohio, 44106
Nationwide Children's Hospital
Columbus, Ohio, 43205
National Jewish Health
Denver, Colorado, 80206
University of Florida
Gainesville, Florida, 32610
University of Indiana
Indianapolis, Indiana, 46202
New Orleans Center for Clinical Research
Knoxville, Tennessee, 37920
University of Pennsylvania
Philadelphia, Pennsylvania, 19104
Maine Medical Center
Portland, Maine, 04102
Oregon Health and Sciences University
Portland, Oregon, 97239
Virginia Commonwealth University
Richmond, Virginia, 23298
University of Utah
Salt Lake City, Utah, 84132
About this study
Official title: A Phase 1/2, Randomized, Double-Blinded, Placebo-Controlled, Combined Single and Multiple Ascending Dose Study Evaluating the Safety, Tolerability, and Biological Activity of MRT5005 Administered by Nebulization to Adult Subjects With Cystic Fibrosis
This Phase 1/2, first-in-human study evaluated the safety and tolerability of single and multiple escalating doses of MRT5005 administered by nebulization to the respiratory tract of adult subjects with cystic fibrosis (CF).
- Conditions
- Cystic Fibrosis
- Being tested
- MRT5005, Normal saline
- Keywords
- Cystic Fibrosis, CF
- Medical subject headings
- Cystic Fibrosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
MRT5005Drug
Nebulization of MRT5005
Normal salineDrug
Normal Saline for Inhalation
| Study group | Role | What they receive |
|---|---|---|
| Part A - SAD Group 1: MRT5005 8 mg | Experimental | Participants received single dose of MRT5005 8 milligrams (mg) by nebulization on Day 1. Receives: Drug: MRT5005 |
| Part A - SAD Group 2: MRT5005 16 mg | Experimental | Participants received single dose of MRT5005 16 mg by nebulization on Day 1. Receives: Drug: MRT5005 |
| Part A - SAD Group 3: MRT5005 20 mg | Experimental | Participants received single dose of MRT5005 20 mg by nebulization on Day 1. Receives: Drug: MRT5005 |
| Part A - SAD Group 4: MRT5005 24 mg | Experimental | Participants received single dose of MRT5005 24 mg by nebulization on Day 1. Receives: Drug: MRT5005 |
| Part A - SAD Groups: Pooled Placebo | Placebo comparator | Participants received single dose of placebo (normal saline) by nebulization on Day 1. Data were analyzed as a pooled population for all participants who received placebo in Part A SAD groups and reported in this arm. Receives: Drug: Normal saline |
| Part B - MAD Group 1: MRT5005 8 mg | Experimental | Participants received MRT5005 8 mg once weekly by nebulization for 5 weeks (i.e., on Day 1, Day 8, Day 15, Day 22 and Day 29). Receives: Drug: MRT5005 |
| Part B - MAD Group 2: MRT5005 12 mg | Experimental | Participants received MRT5005 12 mg once weekly by nebulization for 5 weeks (i.e., on Day 1, Day 8, Day 15, Day 22 and Day 29). Receives: Drug: MRT5005 |
| Part B - MAD Group 3: MRT5005 16 mg | Experimental | Participants received MRT5005 16 mg once weekly by nebulization for 5 weeks (i.e., on Day 1, Day 8, Day 15, Day 22 and Day 29). Receives: Drug: MRT5005 |
| Part B - MAD Group 4: MRT5005 20 mg | Experimental | Participants received MRT5005 20 mg once weekly by nebulization for 5 weeks (i.e., on Day 1, Day 8, Day 15, Day 22 and Day 29). Receives: Drug: MRT5005 |
| Part B - MAD Groups: Pooled Placebo | Placebo comparator | Participants received placebo (normal saline) once weekly by nebulization for 5 weeks (i.e., on Day 1, Day 8, Day 15, Day 22 and Day 29). Data were analyzed as a pooled population for all participants who received placebo in Part B MAD groups and reported in this arm. Receives: Drug: Normal saline |
| Part D: MRT5005 4 mg | Experimental | Participants received MRT5005 4 mg once daily by nebulization from Day 1 to Day 5. Receives: Drug: MRT5005 |
| Part D: Placebo | Placebo comparator | Participants received placebo (normal saline) once daily by nebulization from Day 1 to Day 5. Receives: Drug: Normal saline |
What is being measured
The primary outcome is the main question the study is designed to answer.
Parts A, B and D: Number of Participants With Treatment-Emergent Adverse Events (TEAEs) and Treatment-Emergent Serious Adverse Events
An adverse event (AE) was any untoward medical occurrence in a clinical investigation participant administered a pharmaceutical product and that did not necessarily had a causal relationship with the study treatment. A serious adverse event (SAE) was any untoward medical occurrence (whether considered to be related to study treatment or not) that at any dose: resulted in death; or was life-threatening; or required inpatient hospitalization or prolongation of existing hospitalization; or resulted in persistent or significant disability/incapacity; or was a congenital abnormality/birth defect; or was an important medical event. The TEAEs were defined as events that were newly reported or reported to worsen in severity after the start of study treatment up to 48 weeks (end of follow-up period) after the last dose of study treatment administration.
Measured: From the first dose of study treatment administration (Day 1) up to 48 weeks (end of the follow-up period) after the last dose of study treatment administration (Part A: Day 337, Part B: Day 365 and Part D: Day 341)
Secondary outcomes (1)
Parts A, B and D: Absolute Change From Baseline in Percent Predicted Forced Expiratory Volume in 1 Second (ppFEV1)
Spirometry was performed according to the guidelines published by the American Thoracic Society for standardization of spirometry. The ppFEV1 was assessed during the spirometry testing. For Parts A and B, the baseline value was defined as the average of the results from testing on Day -1 and at pre-dose on Day 1. For Part D, the baseline value was defined as the result from testing pre-dose on Day 1. Here, Baseline= BL, Day= D, pre-dose= PrD, hours post dose= hPD.
Measured: Part A:BL, D1(8hPD), D2(24hPD), D3, D8, D15 and D29; Part B:BL, D1(6hPD), D2, D8(PrD and 6hPD), D9, D15(PrD and 6hPD), D16, D22(PrD and 6hPD), D23, D29(PrD and 6hPD), D30, D36, D43 and D57; Part D:BL, D1(2hPD), PrD on D2, D3, D4 and D5, D11, D18 and D32
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Dec 2017
- Study start10 May 2018
- Primary completion15 Mar 2022
- Study completion15 Mar 2022
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Cystic FibrosisStudies of the same condition, open and under way.
- More trials run by SanofiThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1/2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 42 participants (actual)
Sponsor and investigators
- Lead sponsor
- Sanofi
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03375047
- Sponsor's protocol ID
- MRT5005-101
- Acronym
- RESTORE-CF
- Status last verified
- Feb 2026
- First submitted
- 7 Sep 2017
- Last updated
- 9 Feb 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org
Publications
Miah KM, Hyde SC, Gill DR. Emerging gene therapies for cystic fibrosis. Expert Rev Respir Med. 2019 Aug;13(8):709-725. doi: 10.1080/17476348.2019.1634547. Epub 2019 Jun 27.
PubMed 31215818
Study at a glance
From the registry record, last updated by the sponsor on 9 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 1/2, Randomized, Double-Blinded, Placebo-Controlled, Combined Single and Multiple Ascending Dose Study Evaluating the Safety, Tolerability, and Biological Activity of MRT5005 Administered by Nebulization to Adult Subjects With Cystic Fibrosis
- ClinicalTrials.gov ID
- NCT03375047
- Acronym / sponsor ID
- RESTORE-CF / MRT5005-101
- Conditions
- Cystic Fibrosis
- Keywords
- Cystic Fibrosis, CF
- Phase
- Phase 1/2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 42 participants (actual)
- Lead sponsor
- SanofiIndustry (pharma, biotech, devices)
- Study start
- 10 May 2018 (actual)
- Primary completion
- 15 Mar 2022 (actual)
- Study completion
- 15 Mar 2022 (actual)
- First posted
- 15 Dec 2017 (actual)
- Results
- Posted 9 Feb 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This Phase 1/2, first-in-human study evaluated the safety and tolerability of single and multiple escalating doses of MRT5005 administered by nebulization to the respiratory tract of adult subjects with cystic fibrosis (CF).
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 12
| Arm | Type | Receives |
|---|---|---|
| Part A - SAD Group 1: MRT5005 8 mg | Experimental | Drug: MRT5005Participants received single dose of MRT5005 8 milligrams (mg) by nebulization on Day 1. |
| Part A - SAD Group 2: MRT5005 16 mg | Experimental | Drug: MRT5005Participants received single dose of MRT5005 16 mg by nebulization on Day 1. |
| Part A - SAD Group 3: MRT5005 20 mg | Experimental | Drug: MRT5005Participants received single dose of MRT5005 20 mg by nebulization on Day 1. |
| Part A - SAD Group 4: MRT5005 24 mg | Experimental | Drug: MRT5005Participants received single dose of MRT5005 24 mg by nebulization on Day 1. |
| Part A - SAD Groups: Pooled Placebo | Placebo comparator | Drug: Normal salineParticipants received single dose of placebo (normal saline) by nebulization on Day 1. Data were analyzed as a pooled population for all participants who received placebo in Part A SAD groups and reported in this arm. |
| Part B - MAD Group 1: MRT5005 8 mg | Experimental | Drug: MRT5005Participants received MRT5005 8 mg once weekly by nebulization for 5 weeks (i.e., on Day 1, Day 8, Day 15, Day 22 and Day 29). |
| Part B - MAD Group 2: MRT5005 12 mg | Experimental | Drug: MRT5005Participants received MRT5005 12 mg once weekly by nebulization for 5 weeks (i.e., on Day 1, Day 8, Day 15, Day 22 and Day 29). |
| Part B - MAD Group 3: MRT5005 16 mg | Experimental | Drug: MRT5005Participants received MRT5005 16 mg once weekly by nebulization for 5 weeks (i.e., on Day 1, Day 8, Day 15, Day 22 and Day 29). |
| Part B - MAD Group 4: MRT5005 20 mg | Experimental | Drug: MRT5005Participants received MRT5005 20 mg once weekly by nebulization for 5 weeks (i.e., on Day 1, Day 8, Day 15, Day 22 and Day 29). |
| Part B - MAD Groups: Pooled Placebo | Placebo comparator | Drug: Normal salineParticipants received placebo (normal saline) once weekly by nebulization for 5 weeks (i.e., on Day 1, Day 8, Day 15, Day 22 and Day 29). Data were analyzed as a pooled population for all participants who received placebo in Part B MAD groups and reported in this arm. |
| Part D: MRT5005 4 mg | Experimental | Drug: MRT5005Participants received MRT5005 4 mg once daily by nebulization from Day 1 to Day 5. |
| Part D: Placebo | Placebo comparator | Drug: Normal salineParticipants received placebo (normal saline) once daily by nebulization from Day 1 to Day 5. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Confirmed diagnosis of CF as defined by both of the following:
- Clinically stable CF disease, as judged by the investigator.
- Forced expiratory volume in 1 second (FEV1) ≥50% and ≤90% of the predicted normal for age, gender, and height at screening.
- Resting oxygen saturation ≥92% on room air (pulse oximetry).
Key exclusion criteria (6 listed)
- An acute upper or lower respiratory infection, pulmonary exacerbation, or clinically significant episode of hemoptysis or change in chronic respiratory medications (including antibiotics) for CF lung disease within 28 days prior to dosing with investigational product on Day 1.
- Participants were receiving treatment with ivacaftor monotherapy (KALYDECO).
- Parts A and B only: Were receiving treatment with triple combination therapy (TRIKAFTA).
- Participants with a Class III, IV, or V CFTR gene mutation in at least 1 allele.
- Infection with highly virulent bacteria associated with accelerated decline in pulmonary function and/or decreased survival (e.g., Burkholderia cenocepacia, Burkholderia dolosa, Mycobacterium abscessus).
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| MRT5005Nebulization of MRT5005 | Drug | Part A - SAD Group 1: MRT5005 8 mg, Part A - SAD Group 2: MRT5005 16 mg, Part A - SAD Group 3: MRT5005 20 mg, Part A - SAD Group 4: MRT5005 24 mg, Part B - MAD Group 1: MRT5005 8 mg, Part B - MAD Group 2: MRT5005 12 mg, Part B - MAD Group 3: MRT5005 16 mg, Part B - MAD Group 4: MRT5005 20 mg, Part D: MRT5005 4 mg |
| Normal salineNormal Saline for Inhalation | Drug | Part A - SAD Groups: Pooled Placebo, Part B - MAD Groups: Pooled Placebo, Part D: Placebo |
Primary outcome
Parts A, B and D: Number of Participants With Treatment-Emergent Adverse Events (TEAEs) and Treatment-Emergent Serious Adverse Events
Time frame: From the first dose of study treatment administration (Day 1) up to 48 weeks (end of the follow-up period) after the last dose of study treatment administration (Part A: Day 337, Part B: Day 365 and Part D: Day 341)
An adverse event (AE) was any untoward medical occurrence in a clinical investigation participant administered a pharmaceutical product and that did not necessarily had a causal relationship with the study treatment. A serious adverse event (SAE) was any untoward medical occurrence (whether considered to be related to study treatment or not) that at any dose: resulted in death; or was life-threatening; or required inpatient hospitalization or prolongation of existing hospitalization; or resulted in persistent or significant disability/incapacity; or was a congenital abnormality/birth defect; or was an important medical event. The TEAEs were defined as events that were newly reported or reported to worsen in severity after the start of study treatment up to 48 weeks (end of follow-up period) after the last dose of study treatment administration.
1 secondary outcome
Parts A, B and D: Absolute Change From Baseline in Percent Predicted Forced Expiratory Volume in 1 Second (ppFEV1)
Time frame: Part A:BL, D1(8hPD), D2(24hPD), D3, D8, D15 and D29; Part B:BL, D1(6hPD), D2, D8(PrD and 6hPD), D9, D15(PrD and 6hPD), D16, D22(PrD and 6hPD), D23, D29(PrD and 6hPD), D30, D36, D43 and D57; Part D:BL, D1(2hPD), PrD on D2, D3, D4 and D5, D11, D18 and D32
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Feb 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Derived from this study: PubMed 31215818Miah KM, Hyde SC, Gill DR. Emerging gene therapies for cystic fibrosis. Expert Rev Respir Med. 2019 Aug;13(8):709-725. doi: 10.1080/17476348.2019.1634547. Epub 2019 Jun 27.
- Individual participant dataSharing planned: Yes. Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
16 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1/2 study testing MRT5005 and Normal saline in people with Cystic Fibrosis, run by Sanofi at 16 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 9 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 16 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this combined phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 9 Feb 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Parts A, B and D: Number of Participants With Treatment-Emergent Adverse Events (TEAEs) and Treatment-Emergent Serious Adverse Events (time frame: From the first dose of study treatment administration (Day 1) up to 48 weeks (end of the follow-up period) after the last dose of study treatment administration (Part A: Day 337, Part B: Day 365 and Part D: Day 341)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03375047, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 9 Feb 2026.