Study of Cingal® for Symptomatic Relief of Osteoarthritis of Ankle Joint

Screening Inclusion Criteria:

1. Age 18 years or older

2. Body Mass Index (BMI) ≤ 35 kg/m2

3. Diagnosis of symptomatic osteoarthritic joint in the index ankle (Kellgren-Lawrence
grade I to III) to be treated with Cingal injection.

4. Failed conservative treatment for joint osteoarthritis.

5. NRS pain on walking ≥4 and ≤9 in the index ankle.

6. Subject must be willing to abstain from other treatments of the index ankle for the
duration of the study.

7. Subject is willing to discontinue all analgesics including NSAIDs, except
acetaminophen/paracetamol, at least seven days before the treatment injection and
through the completion of the study.

8. Subject is willing to use only acetaminophen/paracetamol (up to a maximum of 4.0
grams per day per the package insert) for the treatment of joint pain for the
duration of the study. At least forty-eight hours prior to the Baseline Visit and
each follow-up visit, the subject is willing to discontinue use of
acetaminophen/paracetamol.

9. Subject is willing to maintain a stable dose of oral glucosamine and/or chondroitin
sulfate products throughout the study, if taken prior to signing the informed
consent form (ICF).

10. Able and willing to provide signed informed consent

Baseline Inclusion Criteria

1. NRS pain on walking ≥4 and ≤ 9 in index ankle

Screening Exclusion Criteria:

1. History of hypersensitivity to any of the ingredients in the hyaluronan or
corticosteroids

2. Infection or skin disease in the area of the injection site or ankle joint

3. NRS pain on walking > 3 in the contralateral ankle

4. NRS pain on walking > 3 in the ipsilateral knee or hip

5. Subject received an injection of Hyaluronic Acid (HA) and/or steroid in either ankle
within 6 months of signing the informed consent form (ICF). A subject will be
excluded if they are planning to receive an HA or steroid injection (other than the
study injection) in either ankle during the course of this study.

6. Known inflammatory or autoimmune disorders (including rheumatoid arthritis, gout),
or other pre-existing medical conditions that, in the opinion of the investigator,
could impact treatment of the index ankle or affect the ability of the subject to
accurately complete the study questionnaires and comply with the study requirements.

7. Subject is taking medications at the time of signing the ICF which could interfere
with the treatment procedure, healing and/or assessments. This includes but is not
limited to oral or injectable anticoagulant treatments, anti-aggregant platelet
treatment, chronic opioid analgesics. Low dose aspirin used for cardiovascular
protection is allowed if a stable regimen is maintained for the duration of the
study.

8. Subjects who had an oral, intramuscular, intravenous, rectal suppository or topical
(excluded in index ankle only) corticosteroid prior 30 days of signing the ICF are
excluded. Topical corticosteroid use at any site other than the index ankle is
allowed.

9. Significant trauma to the index ankle within 26 weeks of screening

10. Chronic use of narcotics or cannabis.

11. Ligament instability or tear in index ankle.

12. Chronic impingement in the index ankle requiring surgical treatment

13. Diagnosis of fibromyalgia

14. Diagnosis of osteonecrosis in index ankle

15. Subject has significant varus or valgus deformity greater than 10 degrees in either
knee.

16. Subject requires consistent use of an assistive device (e.g. wheelchair, walker,
etc.) Occasional use of a cane is acceptable.

17. Uncontrolled diabetes with HbA1c of >7%.

18. Subject is a woman who is pregnant or breastfeeding at the Screening Visit or a
woman of child bearing potential who refuses to use effective contraception during
the course of the study.

19. Subject is receiving or in litigation for worker's compensation.

20. Otherwise determined by the investigator to be medically unsuitable for
participation in this study.

Baseline Exclusion Criteria

1. Subject has a decrease of ≥ 2 in the NRS pain on walking from Screening to Baseline
in the index ankle.

2. Subject has a contraindication to continue with the study treatment injection based
on the visual appearance of the synovial fluid aspirate.