āshibio Presents Biomarker Data Supporting Vantictumab Development for ADO2 and a Prevalence Estimate of CLCN7 — Related ADO2 of 1—4 per 20,000 Individuals

For best results when printing this announcement, please click on link below: āshibio Presents Biomarker Data Supporting Vantictumab Development for ADO2 and a Prevalence Estimate of CLCN7-Related ADO2 of 1—4 per 20,000 Individuals — Biomarker data demonstrate osteoclast activation at low doses of vantictumab without impacting osteoblast activity, strengthening therapeutic rationale for the treatment of autosomal dominant osteopetrosis type 2 (ADO2) — Analysis of international genetic database is consistent with prior prevalence estimates and suggests a substantial population affected by CLCN7-related ADO2 āshibio ( ), a privately held, clinical-stage biotechnology company developing novel therapeutics for bone and connective tissue disorders, presented new clinical biomarker and genetic prevalence data supporting the development of vantictumab for autosomal dominant osteopetrosis type 2 (ADO2).

These data were presented at the 2026 Annual Meeting of the American Society for Bone and Mineral Research (ASBMR) in Boston, Mass. 5-5mg/kg), administered once weekly (QW) or every two or three weeks (Q2W or Q3W), increased osteoclast activity without inhibiting osteoblast activity, consistent with findings from the ADO2 mouse model presented at the 2025 Annual Meeting of ASBMR(4) and supporting the therapeutic hypothesis that vantictumab can restore bone homeostasis in patients with ADO2.

“We observed a clear exposure-response relationship for bone biomarkers in patients with cancer treated with vantictumab, suggesting we can modify the dose or regimen to activate osteoclasts and restore bone homeostasis without compromising safety in patients with ADO2,” noted Dr. Smith. “Based on analysis of nonclinical toxicity studies, we predict a large therapeutic index for vantictumab, with margins up to 200-fold, consistent with safety data from oncology clinical trials. ” Originally intended for the treatment of cancer, vantictumab has been previously evaluated in oncology clinical trials demonstrating a favorable safety and pharmacokinetic profile.

Analysis of biomarker data from the prior FIH trial supports the advancement of vantictumab into clinical development for ADO2 (also known as Albers-Schönberg disease), a genetic disorder caused by reduced function of osteoclasts. Impaired osteoclast function results in dense, brittle bone and leads to complications such as multiple poorly healing fractures, osteomyelitis, low blood counts (due to bone marrow sequestration), and painful nerve compression.

Of the 31 patients in the Phase 1 study, 29 (94%) experienced a >25% increase in C-terminal telopeptide (βCTX), a measure of the rate of bone resorption, and 23 patients (74%) experienced a ≥50% increase in this bone biomarker post-baseline. 0 mg/kg QW), βCTX elevation was apparent for all participants at day 28 (35-377% of baseline). 5 days), there was a rapid decrease in βCTX upon cessation of dosing. Furthermore, consistent with ADO2 mouse model findings, comparative analysis of bone biomarkers such as βCTX and P1NP indicated selectivity for osteoclast activation versus osteoblast inhibition, especially at lower vantictumab doses.

(5) The most common form of ADO2 results from a mutation in the chloride channel 7 (CLCN7) gene. (6) Data presented at ASBMR provide a contemporary estimate of CLCN7-related ADO2 prevalence using a worldwide genetic database. “Our analysis, using different variant inclusion criteria and a penetrance of 66%, yields a CLCN7-related ADO2 prevalence that increases our confidence in assessing the size of the patient population,” said Deborah Wenkert, MD, Chief Medical Officer of āshibio.

1), a genetic database from worldwide, large-scale sequencing projects, the investigators identified ADO2-related CLCN7 variants from the literature containing supportive radiographic data, supplemented with pathogenic and likely pathogenic (P/LP) variants with clinical information from ClinVar, a public archive of reports of human variations classified for diseases and drug responses. This study provides further support for the lower bound of the total addressable market (TAM) for vantictumab in ADO2, estimated at approximately 40,000 patients in US, Europe, and Japan.

About āshibio āshibio is a privately held, clinical-stage biotechnology company developing a pipeline of novel therapeutics for bone and connective tissue disorders. The company is advancing andecaliximab for the treatment of heterotopic ossification (HO), including fibrodysplasia ossificans progressiva (FOP) and non-hereditary heterotopic ossification (NHHO). āshibio is also developing vantictumab for autosomal dominant osteopetrosis type 2 (ADO2), a genetic disorder characterized by impaired osteoclast function. āshibio intends to advance vantictumab into clinical trials in patients with ADO2 in the first half of 2028.

For more information, visit References (1) Smith V, Lemire I, Mathias A, et al. Vantictumab, a semi-selective FZD inhibitor, activates osteoclasts at low doses in humans. , October 9, 2026, Presentation number Fri-467. (2) Smith DC, Rosen LS, Chugh R, et al.

First-in-human evaluation of the human monoclonal antibody vantictumab (OMP-18/R5; anti-Frizzled) targeting the WNT pathway in a phase I study for patients with advanced solid tumors. J Clin Oncol 31, 2013 (suppl; abstr 2540). (3) Gurney A, Axelrod F, Bond CJ, et al. Wnt pathway inhibition via the targeting of Frizzled receptors results in decreased growth and tumorigenicity of human tumors.

Proc Natl Acad Sci 2012;109(29):11717-22. (4) Alam I, Smith V, Gerard-O’Riley R, et al. Vantictumab, an anti-FZD antibody, Rescues the Osteopetrotic Bone Phenotype in Heterozygous ADO Mice. , September 7, 2025, Presentation number Sun-582.

(5) Wenkert D, Econs MJ, Savarirayan R, Imei EA. 1. , October 10, 2026, Presentation number Sat-496. (6) Bollerslev J, Anderson PE Jr.

Radiological, biochemical and hereditary evidence of two types of autosomal dominant osteopetrosis. Bone. 1988;9(1):7-13. com)