VIENNA — Encouraging primary or secondary analyses of trial data for the use of several novel injectables and gene therapy for knee osteoarthritis (OA) were reported at the OARSI 2024 World Congress.
Of all the approaches discussed during the News in Therapies session at OARSI 2024, the most intriguing was the use of the placental extract PTP-001 (MOTYS, Bioventus), session chair Nancy E. Lane, MD, of the University of California Davis School of Medicine, Sacramento, California, told this news organization.
Other notable presentations of data from trials of investigational agents for knee OA included an update from the SPRINGBOARD phase 2B trial of EP-104IAR, a novel long-acting formulation of the corticosteroid fluticasone propionate; a phase 2 trial of pentosan polysulfate sodium (PPS), a non-opioid, semi-synthetic xylose-based polysaccharide; and an update on phase 2 study results for XT-150, a non-viral, plasmid-based gene therapy designed to express a proprietary variant of interleukin 10 (IL-10).
PTP-001 (MOTYS)
Indeed, promising results were seen in a phase 2 trial testing a single intra-articular (IA) injection of PTP-001 vs an IA saline placebo in just over 200 individuals with symptomatic knee OA. Results of this dose-finding study were presented by Alessandra Pavesio, senior vice president and the chief science officer of Bioventus/Doron Therapeutics, Durham, North Carolina.
Ms. Pavesio reported there were decreases in knee pain and improvements in knee function, as measured using the Western Ontario and McMaster Universities Arthritis Index (WOMAC). These changes were seen after 26 weeks of treatment with PTP-001 given at either a low (100 mg, n = 74) or high (200 mg, n = 40) dose.
Although the changes were only numerically and not statistically different from placebo (n = 71) when looking at the total study population, Ms. Pavesio noted that a key objective of the trial had been to identify populations of patients that may benefit.
When they looked at the effects of PTP-001 solely in those with unilateral knee OA, WOMAC pain scores were decreased to a significantly greater extent with both the high and low doses of PTP-001 vs placebo. Decreases in the least squares mean (LSM) change in WOMAC pain from baseline to week 26 were 26.8 with 100-mg PTP-001, 36.1 with 200-mg PTP-001, and 24.0 with placebo (P = .072). A similarly greater effect for PTP-001 was also seen for LSM change in WOMAC function (26.4, 36.0, and 20.0, respectively; P = .023).
Ms. Pavesio noted that the only real side effect seen during the trial was an initial inflammatory reaction within the first 2 days of IA injection, which resolved within a few days without further problems.
The results are promising enough for Ms. Pavesio and her team to consider a phase 3 trial.
Dr. Lane asked Ms. Pavesio: “So, what’s in the secret sauce? You said it was ground-up placentas?” To which Ms. Pavesio replied that it contained about 300 different molecules which came from amnion, chorion, and umbilical cord tissue obtained from consented placental donation.
Dr. Lane subsequently told this news organization: “It’s probably a bunch of growth factors and cytokines, but if it’s not toxic, and they can standardize it, then it might be good. We remain open minded because we haven’t figured it out.”