Lubricin-inspired Osteoarthritis Treatment: a Unique Solution (LOTUS)

First in Human Safety Evaluation of a Novel Polymer for Knee Osteoarthritis

This goal of this open label study is to evaluate the safety and tolerability of a single intra-articular administration of ABR1 in adults with knee osteoarthritis with a KL grade from 2 to 4. The primary questions it aims to answer are:

1. Is ABR1 safe to use as an intraarticular injection for participants with knee osteoarthritis?
2. What medical problems do participants have after receiving a single injection of ABR1?

Participants will receive a single injection of ABR1 to the knee with osteoarthritis. Participants will

1. Keep a stable pain treatment regimen
2. Visit the clinic at 1 week, 4 weeks, 8 weeks, and 12 weeks post injection
3. Keep a diary of their symptoms and number of times they use a rescue medication for their knee pain.

Study Overview

• Status: Not yet recruiting
• Conditions: Osteo Arthritis of the Knee
• Intervention / Treatment: Device: ABR1

Detailed Description

This first-in-human study is a single-site, open-label, single-arm investigation in adults with knee osteoarthritis from KL grade 2 to 4 evaluating safety and tolerability of a single, ultrasound-guided intra-articular injection of ABR1, while also observing any signals of symptom improvement over 24 weeks post-injection. All enrolled participants will receive a single administration of ABR1 intraarticularly in the target knee and will be followed per protocol for safety monitoring and clinical assessments. Participants should continue to take their medications for pre-existing medical conditions as usual during the trial. Participants will be advised that they may use study allowed rescue medication to treat worsening pain. Participants will record any rescue medication use in their Participant Diary.

Researchers will assess the incidence of adverse events, its relatedness to the device, and the incidence of any treatment-related serious adverse events through Week 12. Patient reported outcomes related to knee osteoarthritis pain will be observed up to Week 24 post injection.

• Study Type: Interventional
• Enrollment (Estimated): 25
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Study Coordinator; Phone Number: 0295625360; Email: lotus.study@sydney.edu.au
• Study Contact Backup: Name: Camilla Herberstein; Phone Number: 0295625360; Email: camilla.herberstein@sydney.edu.au

Study Locations

• Australia
  • New South Wales
    • Sydney, New South Wales, Australia, 2065
      • Royal North Shore Hospital
      • Contact: LOTUS Study Coordinator; Phone Number: 02 95625360; Email: lotus.study@sydney.edu.au

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Male or female at least 40years of age
2. Knee OA with Kellgren-Lawrence (KL) Grade 2 to 4 of the target knee on X-ray

3. Inadequate pain relief with 1st line treatment, consisting of any of the following

   1. conservative non-pharmacological treatment AND/OR
   2. stable dose NSAIDs for at least the past 30 days OR
   3. use of NSAID treatment is contraindicated
4. Target knee pain on most days (at least 15 days per month in the preceding month)
5. Symptomatic knee OA with moderate to severe pain (NRS ≥4 and <9 on Numeric Rating Scale (NRS) with target knee significantly worse than the other knee with a minimum difference of 2-point between knees.
6. Possess cognitive and language ability to complete informed consent and questionnaires
7. Willingness to follow protocol instructions and maintain appointment schedule of the study
8. Willingness to maintain their existing stable regimen (defined as the same regimen for at least the past 30 days) of complementary and non-pharmacological knee OA treatments for trial duration (if any)
9. If participant is taking a stable regimen of NSAIDs - they are willing to maintain their existing stable regimen (defined as taking the same dose for at least the past 30 days) of NSAIDs and not anticipate to change for the duration of the study.
10. Willingness to stop any 'as needed' (PRN) NSAIDs or paracetamol or opioids (except for protocol-permitted rescue pain medication) for the duration of the trial
11. Willingness to stop taking any rescue pain meds 24 hours prior to scheduled follow up clinic visits (except for their stable NSAIDs therapy)

Exclusion Criteria:

1. Pregnant or lactating
2. Other significant knee pathologies of target knee from medical history or radiographic method(s)
3. Severe malalignment > 10 degree in the target knee (either varus or valgus) measured using standardized knee x-ray at screening or based on previous medical records
4. Severe inflammatory arthritis or other joint disease with warm, red, and swollen knee in the target knee
5. History of knee surgery or significant knee trauma of target knee in the past 12 months
6. Received intraarticular injection in the targeted knee joint within the past 6 months
7. Knee surgery or intraarticular injection in the target knee planned in the next 8 months
8. Allergy to rescue pain medication (paracetamol)
9. Unstable/ poorly controlled coagulopathy[CH1.1][LC1.2]
10. Severe anxiety, depression or psychiatric disorder based on self -reported medical history
11. Chronic pain conditions other than knee OA (e.g. cancer, fibromyalgia, pain due to hip OA, etc.) which may interfere with the outcomes of the study, at the discretion of the investigator
12. History of or current substance abuse, self-reported
13. Significant systemic medical comorbidities, e.g. uncontrolled diabetes or hypertension, immunocompromised, cancer, severe cardiovascular disease, neuropathic pain/disorder, etc.
14. ModifiedPainDETECT Questionnaire (mPDQ) >18
15. Current use of any non-opioids centrally acting analgesics including gabapentin, pregabalin, duloxetine, tricyclic antidepressants (e.g. amitriptyline) for pain management within 12 weeks prior to screening.
16. Started taking oral or injectable GLP-1 products in the past 6 months as new regimen. Current use of a GLP-1 product is permitted if the participant has been on the product for > 6 months and plans to continue the product at its current stable dose for the duration of the trial.
17. Started taking another concomitant medication within the past 12 weeks or changed dose of a concomitant medication within the past 12 weeks which could, in the opinion of the Principal Investigator or delegate, impact the participant's safety on the trial or the reliability of the outcome assessments.
18. Participate in another clinical trial and received study intervention currently or in the past 3 months

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Received ABR1; Received a single dose of ABR1	Device: ABR1; Received a single dose of ABR1

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of adverse events	Incidence of treatment-emergent adverse events (TEAEs) through Week 12	from the day receiving study intervention (day 0) to 12 weeks after study intervention

Collaborators and Investigators

• Sponsor: Pleryon Therapeutics (Hangzhou) Limited
• Investigators: Study Chair: Charis Lau, PharmD, OD, MBA, Pleryon Therapeutics Limited; Principal Investigator: David Hunter, MD, Royal North Shore Hospital

Publications and helpful links

General Publications

• Sun Z, Feeney E, Guan Y, Cook SG, Gourdon D, Bonassar LJ, Putnam D. Boundary mode lubrication of articular cartilage with a biomimetic diblock copolymer. Proc Natl Acad Sci U S A. 2019 Jun 18;116(25):12437-12441. doi: 10.1073/pnas.1900716116. Epub 2019 Jun 4.

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2026
• Primary Completion (Estimated): June 1, 2027
• Study Completion (Estimated): December 1, 2027

Study Registration Dates

• First Submitted: May 21, 2026
• First Submitted That Met QC Criteria: May 21, 2026
• First Posted (Actual): May 28, 2026

Study Record Updates

• Last Update Posted (Actual): May 29, 2026
• Last Update Submitted That Met QC Criteria: May 27, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: knee pain; lubrication; intra articular
• Other Study ID Numbers: PC2601

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No