Clinical Trial Finder

Inclusion Criteria:

• - Participants who completed Day 168 of Study PARA_OA_002 (ie, did not discontinue/withdrew prematurely from the parent study).

• - Capable of giving signed informed consent, which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol.

• - Agrees to continue use of paracetamol or topical analgesics (topical NSAIDs are prohibited) as rescue therapy, if required.

Exclusion Criteria:

• - Major surgery or anticipated surgery during the study.

• - Currently hospitalised or any planned hospitalisations during the study.

• - Plan for total knee reconstruction in affected knee(s) during the study.

• - Contraindication to MRI scans.

• - An employee of the Sponsor, clinical research organisations or research site personnel directly affiliated with this study or their immediate family members defined as a spouse, parent, sibling, or child, whether biological or legally adopted.

Treatment

Inclusion Criteria:

• - Body mass index of >=18 to <=39.0 kg/m2.

• - Willing to abstain from use of oral and topical NSAIDs, opioids, and all other systemic pain medications (except acetaminophen/paracetamol per rescue protocol) from 2 weeks before Treatment Day 1 to end of study.

• - Agrees to continue to use acetaminophen/paracetamol or topical analgesics (topical NSAIDs are prohibited) as rescue therapy if required.

Treatment Exclusion Criteria.

• - Major surgery or anticipated surgery during the study.

• - Currently hospitalised or any planned hospitalisations during the study.

• - Plan for total knee reconstruction in affected knee(s) during the study.

• - Contraindication to MRI scans.

• - An employee of the Sponsor, clinical research organisations or research site personnel directly affiliated with this study or their immediate family members defined as a spouse, parent, sibling, or child, whether biological or legally adopted.

• - Documented or reported history of increased bleeding in the absence of anticoagulant or antiplatelet drugs or prior history of major bleeding episode in the presence of anticoagulant or antiplatelet therapy.

• - History of idiopathic or immune-mediated thrombocytopenia (HIT) including history of or laboratory confirmed HIT (positive or equivocal antibodies against platelet factor 4 (anti-PF4).

• - Currently active or recent history (within preceding 12 months) of a gastric or duodenal ulcer, or suspicion of gastrointestinal tract bleeding.

• - Fibromyalgia, regional pain caused by lumbar or cervical compression with radiculopathy, or other moderate to severe pain that may confound assessments or self-evaluation of the pain associated with osteoarthritis.

Participants with a present (current) history of sciatica are not eligible for participation. Participants with a history of sciatica who have been asymptomatic for >= 3 months and who have no evidence of radiculopathy or sciatic neuropathy on thorough neurologic examination are eligible for participation.

• - History of hypersensitivity to PPS, heparin or heparin-like drugs, or drugs of a similar chemical or pharmacological class.

• - Current clinically significant medical conditions, medical history, physical findings, or laboratory abnormality that, in the Investigator's opinion, makes the participant unsuitable for the study.

Chronic medical conditions will be allowed at the discretion of the Investigator but must be stable without necessitating medication changes within 30 days before Treatment Day 1.

• - Presence of any underlying physical or psychological medical condition that, in the opinion of the Investigator, would make it unlikely that the participant will comply with the protocol or complete the study per protocol.

• - Current treatment with anticoagulants or antiplatelet drugs, excluding aspirin ≤100 mg/day.

• - Activated partial thromboplastin time (aPTT) > upper limit of normal (ULN), platelets < 150,000/µL, or liver enzyme tests (aspartate aminotransferase (AST) or alanine aminotransferase (ALT)) >= 2 × ULN at Screening.

• - Values of aPTT at Screening that are below the lower limit of normal should be discussed with the Medical Monitor.

• - Active or chronic hepatitis B virus, hepatitis C virus, or uncontrolled HIV infection (detectable virus or diagnosis of AIDS); participants with HIV infection must be on chronic suppressive antiviral medication.

• - Any clinically significant abnormalities on clinical chemistry, haematology, urinalysis, physical examination, medical history, 12-lead electrocardiogram (ECG), or vital signs as judged by the Investigator (at Screening).

• - Resting, supine blood pressure (BP) ≥ 160 mmHg in systolic pressure or >= 100 mmHg in diastolic pressure at Screening.

If a participant is found to have uncontrolled and/or untreated significant hypertension at Screening and anti-hypertensive treatment is initiated, assessment for study eligibility should be deferred until BP and anti-hypertensive medication have been stable for at least 1 month. For participants with previously diagnosed hypertension, anti-hypertensive medications must be stable for at least 1 month before Screening.

• - Largely or wholly incapacitated (eg, bedridden or confined to a wheelchair, permitting little or no self-care).

• - Major surgery within 12 weeks before treatment Day1or anticipated surgery.

• - Currently hospitalised or any planned hospitalisations during the treatment part.

• - Plan for total knee reconstruction in affected knee(s) during the treatment part.

• - Knee surgery or trauma to the index knee within 1 year before treatment Day 1.

• - A history of drug or alcohol abuse and/or dependence within the 12 months before Screening that, in the opinion of the investigator, may affect participant ability to comply with study requirements.

• - Contraindication to MRI scans.

• - An employee of the Sponsor, clinical research organisations or research site personnel directly affiliated with this study or their immediate family members defined as a spouse, parent, sibling, or child, whether biological or legally adopted.

This is a follow-up extension study to determine duration of treatment effect and assess long-term safety and response to re-treatment with PPS in participants with knee OA pain who completed the parent study study (PARA_OA_002). Study PARA_OA_006 consists of Follow-up Part 1 and Part 2 and a Treatment Part. Eligible participants will be enrolled in Study PARA_OA_006 at the completion of the parent study and will enter the 6-month Follow-up Part 1. At the end of Follow-up Part 1, participants will begin the Treatment Part of the study, continue to Follow-up Part 2, or end the study depending on the treatment received in the parent study, their response to treatment during the parent study, and/or their response status at the end of the Follow-up Part 1. Participants in the Treatment Part will be administered twice weekly subcutaneous (SC) injections for 6 weeks:

• - The PPS dose regimen will be 1 of the 3 dose regimens evaluated in Stage 1 of the parent study and selected by the independent data monitoring committee (DMC).

• - Placebo will be 0.9% w/v sodium chloride injection.

The maximum duration of study participation will be approximately:

• - 28 weeks for participants who complete Follow-up Part 1 and are not eligible to continue to Follow-up Part 2 or the Treatment Part.

• - 56 weeks for participants who complete Follow-up Part 1 and the Treatment Part.

• - 68 weeks for participants who complete Follow-up Part 1, Follow-up Part 2 up to Week 40, and the Treatment Part.

- 80 weeks for participants who complete Follow-up Parts 1 and 2 or Follow-up Part 1, Follow-up Part 2 up to Week 52 and the Treatment Part

Arms

Experimental: Pentosan Polysulfate Sodium

Pentosan Polysulfate Sodium (PPS) at Dose and frequency selected in Stage 1 of Parent Study for 6 weeks

Placebo Comparator: Placebo

Placebo for 6 weeks

Interventions

Drug: - Pentosan Polysulphate Sodium

Subcutaneous Injection (100mg/ml)

Drug: - Placebo (Sodium Chloride Injection, 0.9%)

Placebo to match PPS