Efficacy and safety of a diffusion-based extended-release fluticasone propionate intra-articular injection (EP-104IAR) in knee osteoarthritis (SPRINGBOARD): a 24-week, multicentre, randomised, double-blind, vehicle-controlled, phase 2 trial.

BACKGROUND: Corticosteroids are among the few effective treatments for knee osteoarthritis, but short duration of action limits their utility. EP-104IAR, a long-acting formulation of fluticasone propionate for intra-articular injection, optimises the action of fluticasone propionate through novel diffusion-based extended-release technology. The SPRINGBOARD trial assessed the efficacy, safety, and pharmacokinetics of EP-104IAR in people with knee osteoarthritis. METHODS: SPRINGBOARD was a randomised, vehicle-controlled, double-blind, phase 2 trial done at 12 research sites in Denmark, Poland, and Czech Republic. We recruited adults aged 40 years or older with primary knee osteoarthritis (Kellgren-Lawrence grade 2-3) who reported Western Ontario and McMaster Universities Osteoarthritis Arthritis Index (WOMAC) pain scores of at least 4 and no more than 9 out of 10. Participants were randomly assigned (1:1) to receive one intra-articular dose of 25 mg EP-104IAR or vehicle control. Randomisation was done via interactive web-based access to a central predefined computer-generated list with block size of six (allocated by clinical site). Participants and assessors were masked to treatment allocation. Participants were followed up for 24 weeks. The primary outcome was the difference between groups in change in WOMAC pain score from baseline to week 12, analysed in all participants who were randomly assigned and received treatment. Safety, including laboratory analyses, and pharmacokinetics from quantification of fluticasone propionate in peripheral blood were assessed in all participants who received a dose of randomly assigned treatment. A person with lived experience of knee osteoarthritis was involved in study interpretation and writing of the report. This trial is registered with ClinicalTrials.gov, NCT04120402, and the EU Clinical Trials Register, EudraCT 2021-000859-39, and is complete. FINDINGS: Between Sept 10, 2021, and Nov 16, 2022, 1294 people were screened for eligibility, and 319 were randomly assigned to EP-104IAR (n=164) or vehicle control (n=155). One participant in the EP-104IAR group was excluded from all analyses because treatment was not administered due to an adverse event. 318 participants (135 [42%] male and 183 [58%] female, 315 [99%] White) received randomly assigned treatment and were included in the primary analysis and safety analysis (EP-104IAR, n=163; vehicle control, n=155). At week 12, least squares mean change in WOMAC pain score from baseline was -2·89 (95% CI -3·22 to -2·56) in the EP-104IAR group and -2·23 (-2·56 to -1·89) in the vehicle control group, with a between-group difference of -0·66 (-1·11 to -0·21; p=0·0044); a significant between-group difference persisted to week 14. 106 (65%) of 163 participants in the EP-104IAR group had one or more treatment-emergent adverse event compared with 89 (57%) of 155 participants in the vehicle control group. Effects on serum glucose and cortisol concentrations were minimal and transient. There were no treatment-emergent deaths or treatment-related serious adverse events. Plasma concentrations of fluticasone propionate showed a blunted initial peak with terminal half-life of approximately 18-20 weeks. INTERPRETATION: These phase 2 results suggest that EP-104IAR has the potential to offer clinically meaningful pain relief in knee osteoarthritis for an extended period of up to 14 weeks, longer than published data for currently marketed corticosteroids. There were minimal effects on glucose and cortisol, and stable fluticasone propionate concentrations in plasma. The safety and efficacy of EP-104IAR will be further evaluated in phase 3 trials, including the possibility of bilateral and repeat dosing with EP-104IAR. FUNDING: Eupraxia Pharmaceuticals. TRANSLATION: For the Danish translation of the abstract see Supplementary Materials section.

Safety and pharmacokinetics of EP-104IAR (sustained-release fluticasone propionate) in knee osteoarthritis: A randomized, double-blind, placebo-controlled phase 1 trial.

Objective: EP-104IAR is a novel, sustained-release, intra-articular (IA) formulation of the corticosteroid fluticasone propionate (FP), in development for the treatment of osteoarthritis (OA) pain. This study evaluated the safety, pharmacokinetics (PK) and efficacy of a single dose of EP-104IAR in patients with OA of the knee. Design: This was a multi-center, randomized, double-blind, placebo-controlled trial performed at 3 sites in Canada. Subjects with moderate to severe pain received either a single dose of the investigational product EP-104IAR (15 â€‹mg) or placebo (vehicle) and were evaluated for up to 42 weeks. The primary outcome measures were safety and PK. The study was not powered to assess efficacy, however patient reported outcome measures were analyzed to evaluate pain and symptom relief. Results: Thirty-two subjects were randomized (21 women, 11 men, mean age: 64.8 years). EP-104IAR was well tolerated. Average serum cortisol levels showed no clinically significant deviations compared to placebo and remained within the normal range of cortisol variation. Plasma PK concentrations were within acceptable safety margins, compared to marketed FP products. Synovial fluid FP levels were approximately 2 orders of magnitude higher and at efficacious concentrations for most subjects. Efficacy evaluations indicated that EP-104IAR provided an immediate improvement of OA symptoms and these effects persisted for 8-12 weeks consistently across all measures. Conclusions: This study provides evidence that 15 â€‹mg of EP-104IAR is well tolerated and has the potential for efficacy in OA patients. These data support further examination of EP-104IAR in larger clinical studies.

Pharmacokinetic Profile of Intra-articular Fluticasone Propionate Microparticles in Beagle Dog Knees.

OBJECTIVE: The objective of this pilot study was to determine time point(s) at which maximum concentration of fluticasone propionate (Cmax) occurs in synovial fluid and plasma in Beagle dog knees after intra-articular injection of EP-104IAR. DESIGN: EP-104IAR is composed of fluticasone propionate drug crystals coated with heat-treated polyvinyl alcohol (PVA) to result in extended release properties. Thirty-two Beagle dogs had an injection of EP-104IAR into the knee joint at 2 different dose levels (0.6 mg and 12 mg). Outcome measures included plasma, synovial fluid, and articular cartilage fluticasone propionate concentrations as well as histological analysis of cartilage and synovium at a variety of time points up to 58 days postdosing. RESULTS: Intra-articular administration of 0.6 and 12 mg EP-104IAR was well tolerated. Early minor abnormalities found on microscopy resolved by the end of the study. There were no quantifiable concentrations of fluticasone propionate in plasma of animals administered 0.6 mg at any of the sampling time points. Highest concentrations in plasma following 12 mg administration occurred 1 day postdose and declined with a half-life of approximately 45 days. Highest concentrations of fluticasone propionate in synovial fluid and cartilage generally occurred 5 days postdose in both dose groups and declined with a half-life of approximately 11 to 14 days. CONCLUSIONS: EP-104IAR is capable of providing a safe and prolonged local exposure to a corticosteroid in the synovial joint while minimizing systemic exposure, with peak exposures occurring within a matter of days after dosing before declining in all tissues in a predictable manner.