Clinical trial NCT06724562: This is an Observational Pre-post Study to Observe if the Off Label Use of Anti-IL1 Therapies, Such as Anakinra or Canakinumab, Can Block ACVR1-induced Flare Activity and Heterotopic Ossification in FOP
Official title: An Observational Study of IL1 Inhibition for Blocking ACVR1-Induced Flare Activity and Heterotopic Ossification in Fibrodysplasia Ossificans Progressiva (FOP)
Study type: OBSERVATIONAL
Overall status: RECRUITING
Conditions: Fibrodysplasia Ossificans Progressiva (FOP)
Keywords: heterotopic ossification
canakinumab
anakinra
FOP
Lead sponsor: University of California, San Francisco
Sponsor class: OTHER
Collaborators: name: National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
First posted: 2024-12-09
Enrollment: 11
Sex: ALL
Minimum age (years): 6
Maximum age (years): 17
Standard ages: CHILD
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Subjects with a diagnosis of FOP who meet the inclusion and exclusion criteria will be eligible for participation in this study.

Brief summary: This is an observational pre-post study to observe if the off label use of anti-IL1 therapies, such as anakinra or canakinumab, can block ACVR1-induced flare activity and heterotopic ossification in FOP. It will also generate key tools and preliminary data that are needed to design a future Phase II study.

This study specifically focuses on patients with severe FOP who are being considered by their medical team for rescue therapy with anti-IL1 therapy. Preliminary data suggests patients experience significant decreases in flare frequency when taking anti-IL1 therapy, but other measures of efficacy remain unassessed, such as changes in heterotopic ossification formation, changes in pain medication use, and changes in functionality.

Detailed description: The investigators will perform an observational study on patients with FOP who have decided, along with their primary medical team, to start anti-IL1 therapy with either anakinra or canakinumab due to intractable or unusually severe FOP disease progression. The investigators will study 11 subjects aged 6-17 years old, with a self-reported flare frequency of at least 6 flares/year \[3 times above the average reported FOP population flare frequency of 2 flares/year\] or with an intractable flare that has lasted greater than 3 months. Subjects will begin an observational period during the medication prescription and insurance approval process and will then be followed for up to 1 year after treatment has been initiated by the medical management team. Low-dose whole-body CT (WBCT) imaging, bloodwork, patient-reported outcomes, pain, and flare activity will be assessed during this study.

Eligibility criteria: Inclusion Criteria:

* Patients with a clinical presentation consistent with FOP and a genetic diagnosis of classical FOP (ACVR1R206H variant) (2), male or female aged 6-17 years old.
* Patients with unusually severe FOP disease activity. This will be determined by FOP flare frequency of \>6 flares per year, which is 3 times higher than the reported average in prior FOP studies ; or by a persistent flare that has failed to resolve after 3 months of standard-of-care therapy.
* Patients whose primary medical team has decided that rescue therapy with an anti-IL1 medication should be initiated. Once the primary medical team has decided that anti-IL1 therapy should be pursued, the subject will be told about this clinical-observational study and enrolled in the pre-treatment phase while access to the anti-IL1 therapy is being obtained by the clinical management team.
* Ability to participate in all assessments, including blood draws, radiology assessments, and travel. Age 6 is chosen as the lower limit to avoid the need for anesthesia for whole body CT in younger subjects.
* No history of unexplained infections, known autoimmune disease, or contraindication to anti-IL1 therapy.
* Written informed consent (and assent when applicable) obtained from subject or subject's legal representative and ability for subject to comply with the requirements of the study.

Exclusion Criteria:

* Pregnant, breastfeeding, or unwilling to practice birth control during participation in the study.
* Presence of a condition or abnormality that in the opinion of the Investigator would compromise the safety of the patient or the quality of the data.
* Inability to travel to site for assessments
* Pre-existing autoimmune or autoinflammatory disease (aside from FOP)
* Inability to tolerate assessments (such as phlebotomy)
* Unexplained infections
* Current participation in an interventional trial, or study of a potentially disease modifying medication
* Inability to take medications as prescribed by managing physician

Primary outcomes:
measure: Number of flares that a patient experiences.
timeFrame: 1 year
Secondary outcomes:
measure: Change in new heterotopic ossification bone formation over time
timeFrame: 1 year
measure: Changes in blood inflammatory cytokine levels with anti-IL1 therapy
timeFrame: 1 year
measure: Change in patient mobility
timeFrame: 1 year
measure: Number of participants with treatment emergent adverse events (TEAEs)
timeFrame: 1 year
Other outcomes:
Locations:
city: San Francisco
country: United States
facility: UCSF
state: California
Study officials:
affiliation: University of California, San Francisco
name: Edward Hsiao, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Haviv R, Zeitlin L, Moshe V, Ziv A, Rabinowicz N, De Benedetti F, Prencipe G, Matteo V, De Cunto CL, Hsiao EC, Uziel Y. Long-term use of interleukin-1 inhibitors reduce flare activity in patients with fibrodysplasia ossificans progressiva. Rheumatology (Oxford). 2024 Sep 1;63(9):2597-2604. doi: 10.1093/rheumatology/keae255.
citation: Haviv R, Moshe V, De Benedetti F, Prencipe G, Rabinowicz N, Uziel Y. Is fibrodysplasia ossificans progressiva an interleukin-1 driven auto-inflammatory syndrome? Pediatr Rheumatol Online J. 2019 Dec 21;17(1):84. doi: 10.1186/s12969-019-0386-6.