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Study on the Effects of Pentosan Polysulfate Sodium for Knee Osteoarthritis Pain in Adults

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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying the effects of a treatment for knee osteoarthritis pain. The treatment being tested is called Pentosan Polysulfate Sodium, also known by its code name PPS. This study aims to evaluate how effective PPS is in reducing knee pain and improving knee function in people who suffer from knee osteoarthritis pain.

Participants in the study will receive either the PPS treatment or a placebo. The study is designed to be conducted in two stages, and it is randomized, meaning participants are randomly assigned to receive either the treatment or the placebo. The study is also double-blind, which means neither the participants nor the researchers know who is receiving the treatment or the placebo during the study. This helps ensure that the results are not biased.

The study will take place over a period of several weeks. Participants will be monitored for changes in their knee pain and function, with assessments conducted at specific intervals. The main goal is to see if there is a significant improvement in knee pain and function for those receiving the PPS treatment compared to those receiving the placebo. This study is important for understanding the potential benefits of PPS for individuals with knee osteoarthritis pain.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial visit

    Upon joining the study, you will attend an initial visit where your eligibility will be confirmed. This includes a review of your medical history and a physical examination.

    You will be asked to stop taking any oral and topical non-steroidal anti-inflammatory drugs (NSAIDs) and other systemic pain medications, except for acetaminophen/paracetamol, two weeks before the first day of the study.

  2. Step 2

    Baseline assessment

    At the start of the trial, a baseline assessment will be conducted. This involves measuring your knee pain and function using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Numeric Rating Scale.

    Your body mass index (BMI) will also be recorded to ensure it falls within the required range of 18.0 to 39.0 kg/m².

  3. Step 3

    Treatment phase

    You will be randomly assigned to receive either the study medication, pentosan polysulfate sodium, or a placebo. The medication will be administered as a solution for injection under the skin.

    The treatment will be given according to the study schedule, and you will be required to attend regular visits for monitoring and assessment.

  4. Step 4

    Follow-up assessments

    Throughout the study, follow-up assessments will be conducted to evaluate changes in your knee pain and function. These assessments will occur at specified intervals, including Day 56 and Day 84.

    Your progress will be monitored using the WOMAC Numeric Rating Scale to track any changes from the baseline.

  5. Step 5

    End of study

    At the end of the study, a final assessment will be conducted to evaluate the overall effect of the treatment on your knee pain and function.

    You will have the opportunity to discuss your experience and any concerns with the study team.

Who can join the trial?

8 criteria

  • Participants must be 18 years of age or older.
  • Must have a clinical diagnosis of knee osteoarthritis (OA) in the affected knee, according to the American College of Rheumatology 1986 criteria. This means a doctor has confirmed you have knee OA.
  • Must have a radiographic diagnosis of knee OA, confirmed by a radiologist, classified as K-L Grade 2, 3, or 4. This means an X-ray shows the level of OA in your knee.
  • Must have knee osteoarthritis pain that has not improved with usual treatments for at least 6 months before the screening.
  • Must have an average pain score between 4 to 10 on a specific pain scale for the affected knee at screening. Also, must have a minimum pain score of 4 for pain when walking on a flat surface or climbing stairs.
  • Must have an average function score between 4 to 10 on a specific function scale for the affected knee at screening.
  • Must have a body mass index (BMI) between 18.0 to 39.0 kg/m². BMI is a measure of body fat based on height and weight.
  • Must be willing to stop using oral and topical NSAIDs (non-steroidal anti-inflammatory drugs) and all other systemic pain medications, except acetaminophen/paracetamol, from 2 weeks before the start of the study until the end.

Who cannot join the trial?

10 criteria

  • Patients who have had a knee replacement surgery.
  • Patients with severe knee deformities.
  • Patients with other types of arthritis, such as rheumatoid arthritis.
  • Patients who have had a recent injury to the knee.
  • Patients who are currently participating in another clinical trial.
  • Patients with a known allergy to the study medication.
  • Patients who are pregnant or breastfeeding.
  • Patients with uncontrolled medical conditions, such as high blood pressure or diabetes.
  • Patients with a history of drug or alcohol abuse.
  • Patients who are unable to comply with the study procedures.
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Investigated drugs

Pentosan Polysulfate Sodium is a medication being studied for its potential to relieve pain and improve function in people with knee osteoarthritis. Osteoarthritis is a condition that causes pain and stiffness in the joints, and this medication is thought to help by reducing inflammation and possibly protecting the cartilage in the knee. The study aims to see how effective this medication is in reducing knee pain and improving the ability to move and use the knee in everyday activities.

What is already known about the treatment

Pentosan Polysulfate Sodium – This medication is administered orally in the form of capsules. It is currently being studied in clinical trials to assess its effectiveness in treating knee osteoarthritis pain. The main therapeutic indication for Pentosan Polysulfate Sodium is to alleviate pain and improve function in individuals suffering from knee osteoarthritis. At the molecular level, it works by inhibiting certain enzymes that break down cartilage, thereby reducing inflammation and pain in the joints. It is classified pharmacologically as a disease-modifying osteoarthritis drug (DMOAD).

Investigated diseases

Osteoarthritis of the Knee – Osteoarthritis of the knee is a degenerative joint disease characterized by the breakdown of cartilage in the knee joint. As the cartilage wears away, bones begin to rub against each other, causing pain, swelling, and reduced motion in the joint. Over time, the joint may become stiffer and more painful, especially after periods of inactivity or excessive use. The condition can lead to the formation of bone spurs and a grating sensation during movement. It typically progresses slowly, with symptoms worsening over time. Factors such as age, weight, previous injuries, and genetics can influence the progression of the disease.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IVTrial ID2022-500228-31-01Protocol codePARA_OA_002Estimated enrolment938 patientsSponsorParadigm Biopharmaceuticals (USA) Inc.

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