TPX-100: OrthoTrophix Presents New Data Revealing Structural Coupling between Femoral Bone Shape and Meniscal Pathology in Knee Osteoarthritis

FOSTER CITY, Calif., April 24, 2026 /PRNewswire/ -- OrthoTrophix, Inc., a privately held biopharmaceutical company, today announced new clinical data demonstrating a significant association between femoral subchondral bone shape, measured by B-score, and meniscal pathology in patients with knee osteoarthritis (KOA). These findings add to the growing body of evidence supporting the role of bone-shape metrics as reproducible, quantitative structural measures that may reflect disease severity and progression in KOA.

The Company is presenting a late-breaking abstract entitled, "WORMS-Defined Meniscal Pathology is Associated with Femoral Bone-Shape Change, with Attenuation in IA TPX-100 Treated Knees" (Poster #665) at the Osteoarthritis Research Society International (OARSI) 2026 World Congress in West Palm Beach, Florida (23 – 26 April 2026). The poster is being presented April 24 – 25.

WORMS (Whole Organ Magnetic Resonance Imaging Score) is a semi-quantitative MRI-based method used to assess structural features of KOA across multiple joint tissues. In this retrospective imaging analysis, femoral bone shape – quantified using the B-score – demonstrated statistically significant associations with WORMS-defined meniscal pathology across timepoints.

The meniscus plays a central role in load distribution and joint stability, and its degeneration is a known contributor to KOA progression. These findings indicate that meniscal damage and subchondral bone-shape change co-evolve in KOA and may reflect shared biomechanical pathways related to altered load transmission and joint degeneration.

Longitudinal analyses showed that in placebo-exposed knees, the association between meniscal pathology and bone-shape change strengthened over time, consistent with progressive structural coupling during disease progression. In contrast, TPx-100-treated knees demonstrated stabilization of bone shape change and attenuation of this relationship. While exploratory, these findings suggest that TPX-100 may influence structural disease trajectories in KOA.

OrthoTrophix is also presenting a second abstract, "More Severe Baseline Meniscal Pathology Predicts Greater, Sustained Response to IA TPX-100: A WORMS Analysis from a Randomized Trial" (Poster #664). This analysis demonstrated that patients with more severe baseline pathology experienced greater and more sustained improvements in patient-reported outcomes (PROs), including WOMAC Function, following treatment with TPX-100 compared to placebo. These findings suggest that baseline meniscal pathology may act as a potential effect modifier, identifying a subgroup of patients with reduced placebo responsiveness and greater treatment separation. Meniscal disease burden may help identify patients who are especially likely to benefit from TPX-100.

"These data provide new insight into the relationship between meniscal pathology and subchondral bone remodeling in OA," said Dawn McGuire, M.D., Chief Medical Officer of OrthoTrophix. "Together, these analyses provide convergent, imaging-based evidence linking meniscal pathology and subchondral bone remodeling in KOA, and support continued prospective evaluation of TPX-100 as a potential modifier of structural disease progression. These findings also may inform patient stratification strategies in future clinical trials. In addition, they support further evaluation of femoral bone-shape metrics as quantitative structural measures in KOA."

About OrthoTrophix, Inc.

OrthoTrophix, Inc., based in the San Francisco Bay Area, is a privately held biopharmaceutical company focused on the developing first-in-class therapies that protect and preserve joint integrity in osteoarthritis and related hard tissue disorders. Founded in 2011, OrthoTrophix is advancing targeted disease-modification strategies to slow or stop disease progression and improve long term patient outcomes. OrthoTrophix has partnered with American Regent, Inc. (https://americanregent.com/) on its DMOAD candidate, TPX-100, for the U.S. market and retains the rights for the rest of the world.

This press release contains "forward-looking" statements. These statements involve risks and uncertainties, which may cause results to differ materially from those set forth in the statements. The forward-looking statements include statements regarding product development and cannot be guaranteed. OrthoTrophix undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events, or otherwise. Forward-looking statements in this press release should be evaluated together with the many uncertainties that affect OrthoTrophix' business.

Company Contact
Yoshi Kumagai
President and CEO
Tel: (510) 488-3824

SOURCE OrthoTrophix, Inc.