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A Double-blind, Randomized, Intra-subject Placebo-controlled, Multicenter, Multiple Dose Study, Evaluating Safety, Proof of Mechanism, Preliminary Efficacy and Systemic Exposure in Subjects With Confirmed DDEB or RDEB Diagnosis With One or More Pathogenic Mutations in Exon 73 in the COL7A1 Gene

Phase 1
Terminated
Conditions
Epidermolysis Bullosa Dystrophica, Recessive
Epidermolysis Bullosa Dystrophica, Dominant
Interventions
Drug: Placebo
Registration Number
NCT03605069
Lead Sponsor
Phoenicis Therapeutics
Brief Summary

A double-blind, randomized, intra-subject placebo-controlled, multicenter, multiple dose study, evaluating safety, proof of mechanism, preliminary efficacy and systemic exposure in subjects with confirmed DDEB or RDEB diagnosis with one or more pathogenic mutations in exon 73 in the COL7A1 gene.

Detailed Description

This clinical trial will evaluate the safety and tolerability, proof of mechanism, systemic exposure and preliminary efficacy following topical application of QR-313 to subjects with confirmed DDEB or RDEB with one or more pathogenic mutations in exon 73 in the COL7A1 gene.

Up to two Target Wound Areas (TWAs) per subject will be selected and randomized. Each TWA will be treated with IMP for 8 weeks, either QR-313 or matching placebo. All subjects will continue to be followed up for 8 weeks post last dose.

Subjects will be monitored through home visits and site visits. An imaging system will be used to assess the target wound at all home and study site visits.

QR-313 is a 21-nucleotide antisense oligonucleotide (AON) designed to hybridize to a specific sequence in the COL7A1 pre-messengerRNA (pre-mRNA).

Recruitment & Eligibility

Status
TERMINATED
Sex
All
Target Recruitment
2
Inclusion Criteria
  1. Male or female, ≥ 4 years of age at Screening with a clinical diagnosis of DDEB or RDEB and at least one pathogenic mutation in exon 73 of the COL7A1 gene.

  2. Have at least one TWA, ie, a skin area of 7 x 7 cm that ishows no signs of local infection, and contains a target wound that is either new or shows dynamic wound healing and complies to the following additional criteria:

    1. surface area of the target wound ranging from 5 to 30 cm2, located centrally in the selected 7 x 7 cm TWA.
    2. exposed sub-epidermal tissue to allow absorption of the IMP.
    3. no suspicion of current squamous cell carcinoma (SCC) upon visual inspection.
Exclusion Criteria
  1. Pregnant or breast-feeding female
  2. Hemoglobin level at Screening requiring transfusion. The subject may be rescreened when the condition is considered stable.
  3. Use of aminoglycosides, by any route of administration, except eye drops, 7 days or 5 half-lives, whichever is longer, prior to Baseline visit.
  4. Untreated carcinoma of the TWA or history of carcinoma within 5 years prior to Screening, except adequately treated cutaneous squamous or basal cell carcinoma.
  5. Life expectancy less than 6 months, as assessed by the Investigator
  6. Current or known history of clinically significant hepatic or renal disease, that in the opinion of the Investigator, could impact subject safety or study participation.
  7. Treatment with any systemic immunomodulators, immunosuppressants or cytotoxic chemotherapy within 2 months prior to the Baseline visit.
  8. Use of any investigational drug or device within 28 days or 5 half-lives of the Baseline visit, whichever is longer, or plans to participate in another study of a drug or device during the study period. The washout of 5 half-lives does not apply to gene and cell therapy.
  9. Known hypersensitivity to oligonucleotide treatment or excipients of the IMP.
  10. Bleeding disorder or condition requiring the use of anticoagulants to be confirmed by aPTT by local lab within 48 hours of first treatment.
  11. Use of systemic or topical steroids within 1 month prior to the baseline visit (inhaled and ophthalmic drops of corticosteroids or low dose topical solution of budesonide for esophagial strictures may be allowed).

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
First TWA (A)PlaceboIn each subject up to two target wound areas (TWA) are randomized, one each to active treatment or placebo. In the first arm; randomization of the first selected TWA to active treatment or placebo
Second TWA (B)PlaceboIn each subject, in the second arm; allocation of the second selected target wound area (TWA) to the alternative treatment. Second arm in the same subject as the first arm.
First TWA (A)QR-313In each subject up to two target wound areas (TWA) are randomized, one each to active treatment or placebo. In the first arm; randomization of the first selected TWA to active treatment or placebo
Second TWA (B)QR-313In each subject, in the second arm; allocation of the second selected target wound area (TWA) to the alternative treatment. Second arm in the same subject as the first arm.
Primary Outcome Measures
NameTimeMethod
To assess the effect of QR-313 on the exclusion (skipping) of exon 73 from COL7A1 mRNAafter 4 weeks of treatment with IMP

Absence of exon 73 in COL7A1 mRNA, detected by droplet digital polymerase chain reaction (ddPCR)

Incidence of treatment emergent adverse events/serious adverse eventsthrough 8 weeks after last dose of IMP (EOS)

Assessment of treatment emergent adverse events/serious adverse events

Secondary Outcome Measures
NameTimeMethod
Assessment of wound healing and skin strength as assessed by Physician Subjective Assessment of Change (PSAC)through 8 weeks after last dose of IMP (EOS)

Wound change in severity as assessed by Physician Subjective Assessment of Change (PSAC), a 3-point Likert static scale that classifies a wound as mild, moderate or severe.

Assessment of the effect of QR-313 on the presence of collagen type VII protein and anchoring fibrilsafter 8 weeks of treatment

Presence of anchoring fibrils (TEM)

Assessment of wound healing and skin strength measured in surface area (cm2)through 8 weeks after last dose of IMP (EOS)

Wound size (surface area in cm2)

Assessment of systemic exposure after topical administration of QR-313 to the target wound area (TWA)Day 1 and after 4 and 8 weeks of treatment and EOS

Serum levels of QR-313

Assessment of wound healing and skin strength as assessed by Physician Subjective Assessment of Severity (PSAS)through 8 weeks after last dose of IMP (EOS)

Wound severity as assessed by Physician Subjective Assessment of Severity (PSAS), a 3-point Likert static scale that classifies a wound in mild, moderate or severe

Assessment of wound healing and skin strength as assessed by Short Wound Specific Questionnaire (SWSQ)through 8 weeks after last dose of IMP (EOS)

Wound status as assessed by Short Wound Specific Questionnaire (SWSQ) addressing three domains: pruritus, pain, and inflammation. Pruritus and pain are recorded as a Patient Reported Outcome (PRO) measure. Inflammation is reported as an Observer Reported Outcome (ObsRO) measure.

Assessment of wound healing and skin strength measuring onset of (re)blistering of a healed woundthrough 8 weeks after last dose of IMP (EOS)

Onset of (re)blistering of a healed wound

Trial Locations

Locations (6)

Journey Clinic, Center for Pediatric Blood and Marrow Transplantation

🇺🇸

Minneapolis, Minnesota, United States

Stanford University School of Medicine, LPCH

🇺🇸

Palo Alto, California, United States

Children's Hospital Colorado

🇺🇸

Aurora, Colorado, United States

Hospital Universitario La Paz

🇪🇸

Madrid, Spain

Hopital Necker Enfants Malades

🇫🇷

Paris, France

Cincinnati Children's Hospital

🇺🇸

Cincinnati, Ohio, United States

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