A Rollover Study to Further Evaluate the Safety and Efficacy of Palovarotene Capsules in Male and Female Participants Aged ≥14 Years With Fibrodysplasia Ossificans Progressiva (FOP) Who Have Completed the Relevant Parent Studies.

An adverse event (AE) was any untoward medical occurrence in a clinical study participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. An SAE was defined as any untoward medical occurrence that, at any dose, resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect or significant medical event. A TEAE was defined as any AE that occurred after signing the informed consent form of this study or an ongoing AE from the parent study with a worsening in severity or relationship to the study treatment following transition to this study.

The CAJIS is an objective measure of joint movement completed by the investigator to document total joint involvement. This scale assesses functional disability by categorizing range of motion across 12 joints (both right and left shoulder, elbow, wrist, hip, knee and ankle joints) and 3 body regions (cervical spine, thoracic/lumbar spine and jaw), with each joint/region assessed as: 0=normal (<10% deficit); 1=partially impaired (10% to 90% deficit) and 2=functionally ankylosed (>90% deficit). The CAJIS total score is calculated as the sum of the scores of all joints/regions and ranges from 0 (no involvement) to 30 (maximally involved). Higher score indicated worse outcome. The Inclusion Visit was the first study visit (Day 1) and first administration of palovarotene in this study.

The use of assistive devices and adaptations (aids) for daily living was collected using the FOP assistive devices assessment at each visit. Assistive devices and adaptations include mobility aids, eating tools, personal care tools, bathroom aids and devices, bedroom aids and devices, home adaptions, work environment adaptions, technology adaptions, sports and recreation adaptions, school adaptions and medical therapies for daily living. The mean of total number of assistive devices and adaptations for daily living being used is presented. The Inclusion Visit was the first study visit (Day 1) and first administration of palovarotene in this study.

The FOP-PFQ is a disease-specific patient-reported outcome measure of physical impairment; includes 28 questions related to activities of daily living and physical performance scored on a scale of 1 to 5 with lower scores indicating that participant has more difficulty completing those tasks. Total score, upper extremities subscore and mobility subscore is calculated as follows: total score: sum of the scores from each question (range 28 to 140); upper extremities subscore: sum of the scores from 15 questions (questions 1-12, 14, 25 and 26; range 15 to 75); mobility subscore: the sum of the scores from 13 questions (questions 13, 15-24, 27 and 28; range 13 to 65). The scores were transformed to reflect a percentage of worst score which ranged from 0% to 100% with 0% indicating the best possible function and 100% (higher score) indicating the worst possible function. Mean is presented. Inclusion Visit was first study visit (Day 1) and first administration of palovarotene in this study.

Annualized HU rate was defined as the (number of HU during the study/duration of participant participation in the study in days) * 365.25. Annualized rate for total health care services utilized is presented.

Lung function parameters including FVC were obtained by spirometry. The Inclusion Visit was the first study visit (Day 1) and first administration of palovarotene in this study.

Lung function parameters including FEV1 were obtained by spirometry. The Inclusion Visit was the first study visit (Day 1) and first administration of palovarotene in this study.

The ratio of FEV1 to FVC was calculated. Lung function parameters were obtained by spirometry. The Inclusion Visit was the first study visit (Day 1) and first administration of palovarotene in this study.

The DLCO test provides information on the efficiency of gas transfer from alveolar air into the bloodstream. The Inclusion Visit was the first study visit (Day 1) and first administration of palovarotene in this study.

The PROMIS Global Health Scale is a patient-reported outcome measure of physical and mental function. The adult form (developed for participants >=15 years old) was used for all participants,consists of 10 questions from which 2 scores are calculated: global physical health score (GPH) and global mental health (GMH) score, each ranging from 4 (worse health) to 20 (better health). GPH score:sum of scores from Questions 3, 6, 7 and 8 and GMH score:sum of scores from Questions 2, 4, 5 and 10.These scores were converted to a T-score whose distributions were standardized such that value of 50 represented average (mean) for general population and increments of +/- 10 points represented +/- 1 standard deviation away from the norm.Higher T-scores indicated better physical/mental health. A T-score <50 indicated worse health than general population, while a T-score >50 indicated better health. Inclusion Visit was first study visit (Day 1) and first administration of palovarotene in this study.

Number of participants with at least 1 flare-up and intercurrent flare-ups since last visit is presented. Intercurrent flare-ups were defined as a new flare-up or marked worsening of the original flare up at any time during a flare-up-based treatment cycle. Outcome of flare-ups resulting in movement restriction and bone formations in participants is presented. Movement restriction includes categories like better, same, slightly worse, moderately worse and severely worse movement than before.

Number of participants with flare-ups by body locations including shoulder, elbow, hip, knee, ankle or foot, back, jaw and submandibular area and other (includes all other locations than mentioned) is presented.

Duration of flare-up was defined as (date of end of flare-up - date of start of flare-up + 1).

Percentage of participants with at least 1 extra bone growth associated or not with a flare-up since last visit is presented.