for people ages up to 65 years (full criteria)
at San Francisco, California and other locations
study started
estimated completion
Edward Hsiao



Fibrodysplasia Ossificans Progressiva (FOP) is a rare, severely disabling disease characterized by painful, recurrent episodes of soft tissue swelling (flare-ups) that result in abnormal bone formation in muscles, tendons, and ligaments. Flare-ups begin early in life and may occur spontaneously or after soft tissue trauma, vaccinations, or influenza infections. Recurrent flare-ups progressively restrict movement by locking joints leading to cumulative loss of function and disability. This 3-year, non-interventional, two-part, natural history study is designed to gain insight into total body HO, FOP disease progression, the impact of FOP on subjects' physical functioning, and clinical features and biomarkers that may be useful in the diagnosis and monitoring of disease progression. This natural history study will also provide important information to inform the design of subsequent interventional trials.

Official Title

A Natural History, Non-Interventional, Two-Part Study in Subjects With Fibrodysplasia Ossificans Progressiva (FOP)


This is a multi-center, natural history, non-interventional, longitudinal study in subjects with classic FOP. A thorough baseline examination will be performed to determine the current status of disease in each subject. In Part A, two imaging modalities assessed total body HO at baseline, and the optimal method (low-dose whole body CT scan [excluding head]) will be employed in Part B for the balance of the study. Progression will be assessed at annual in-clinic visits (ie, at Months 12, 24, and 36) at which time the procedures conducted at the baseline visit will be repeated. In addition, site personnel will telephone subjects midway between the annual visits (ie, at Months 6, 18, and 30).

During the 36-month follow-up period, at least one new flare-up (with a maximum of one per year) will be carefully studied. An in-clinic visit will be performed within 14 days following the subject's identification of his/her flare-up. Additional visits at Day 42 and Day 84 (after the initial flare-up clinic visit) will be performed. An additional future visit may be scheduled after Day 84 at the discretion of the Principal Investigator (PI) for prolonged flare-ups. However, subjects with an eligible flare-up may elect to participate in an ongoing Clementia interventional study rather than continue in this natural history study.


Fibrodysplasia Ossificans Progressiva Natural History Study Non-interventional Study Observational Study Heterotopic ossification FOP disease progression FOP flare-up progression Clementia Myositosis Ossificans Progressiva Munchmeyer's Disease FOP Palovarotene Myositis Ossificans


You can join if…

Open to people ages up to 65 years

  • Subjects clinically diagnosed with classical FOP with documented R206H mutation or believed to carry the R206H mutation

You CAN'T join if...

  • Participation in an interventional clinical research study within the 4 weeks prior to enrollment


  • University of California San Francisco, Division of Endocrinology and Metabolism
    San Francisco California 94143 United States
  • University of Pennsylvania, Center for FOP & Related Bone Disorders
    Philadelphia Pennsylvania 19104 United States

Lead Scientist

  • Edward Hsiao
    Residency: Johns Hopkins Hospital, Baltimore, MD, Internal Medicine, 2001-2004 Fellowship: UCSF, Division of Diabetes, Endocrinology and Metabolism, 2004-2007 Board Certifications: Internal Medicine, 2004; Endocrinology and Metabolism, 2006 My research is driven by a desire to understand how major hormonal and regulatory pathways determine the specification, differentiation, a…


in progress, not accepting new patients
Start Date
Completion Date
Clementia Pharmaceuticals Inc.
website for the International FOP Association
more information about this study: A Natural History, Non-Intervention Study in Subjects with Fibrodysplasia Ossificans Progressiva (FOP)
Study Type
Last Updated