New Taipei City, Taiwan, November 9, 2026
GlycoNex, Inc., a clinical-stage biotechnology company focused on antibody-drug conjugates (ADCs) and biosimilar development, has announced the submission of a Marketing Authorization Application (MAA) for SPD8, its denosumab biosimilar candidate, to Japan’s Pharmaceuticals and Medical Devices Agency (PMDA). The candidate was co-developed with Mitsubishi Gas Chemical (MGC) and is being developed as a treatment for osteoporosis. This regulatory milestone follows positive results from a pivotal Phase III clinical trial conducted in Japan, which demonstrated therapeutic equivalence between SPD8 and the reference denosumab product. The company expects a regulatory decision in Japan as early as the end of 2027, subject to PMDA review and approval. The submission represents an important advancement in GlycoNex’s biosimilar development strategy and brings the investigational product closer to potential commercialization. The company is also preparing for a regulatory submission in Taiwan while exploring commercialization partnerships for markets outside Japan.
Japanese Regulatory Submission Marks Major Milestone
The submission of SPD8 to the PMDA represents a significant step in GlycoNex’s efforts to develop and commercialize its denosumab biosimilar. SPD8 is designed as a biosimilar to denosumab, a fully human monoclonal antibody that targets receptor activator of nuclear factor kappa-B ligand (RANKL), a protein involved in bone breakdown. By inhibiting RANKL activity, denosumab reduces the formation and activity of osteoclasts, the cells responsible for bone resorption. This mechanism helps maintain bone mineral density and supports the management of osteoporosis. Denosumab is marketed under the brand names Prolia and Xgeva for different approved indications. GlycoNex is initially advancing SPD8 for the treatment of osteoporosis in Japan. The regulatory application follows the completion of its clinical development program, including a Phase III study designed to establish therapeutic equivalence to the reference biologic. The company anticipates a possible Japanese regulatory decision by the end of 2027, although the final timeline will depend on the regulatory review process. GlycoNex plans to work with its partners to support the assessment and prepare for a potential commercial launch if approval is granted.
Phase III Trial Demonstrates Therapeutic Equivalence
The Japanese regulatory submission is supported by positive topline findings from a randomized, double-blind, multicenter Phase III clinical trial involving 266 patients with osteoporosis. The study was designed to compare SPD8 with reference denosumab and evaluate whether the biosimilar candidate demonstrated comparable therapeutic performance. The trial successfully met its primary endpoint, demonstrating therapeutic equivalence based on the percentage change from baseline in lumbar spine bone mineral density (BMD) at Month 12. The study evaluated patients over a 12-month treatment period, providing clinical evidence supporting the biosimilar development program. Lumbar spine BMD is an important measurement used in osteoporosis research to assess changes in bone density during treatment. The successful achievement of the primary endpoint represents an important clinical milestone because demonstrating similarity to the reference biologic is a central requirement in biosimilar development. These Phase III results provided the clinical foundation for GlycoNex’s Japanese marketing authorization application. However, the trial’s reported primary endpoint concerns bone mineral density equivalence and should not be interpreted as direct proof of superior fracture prevention or clinical benefit over the reference product.
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Global Commercialization and Biosimilar Development Strategy
Beyond the Japanese submission, GlycoNex is expanding its plans for the potential commercialization of SPD8 in additional markets. The company retains sales, distribution and commercialization rights outside Japan and is actively seeking regional partners to support future market access. Regulatory preparations for Taiwan are also underway, with submission strategies for other countries to be determined according to their respective regulatory requirements. The collaboration with Mitsubishi Gas Chemical is an important component of the program’s development history, combining expertise to advance the denosumab biosimilar toward regulatory approval. GlycoNex aims to establish a sustainable biosimilars business alongside its innovative glycan-directed ADC research pipeline. The experience gained through SPD8 is also expected to support the advancement of the company’s second biosimilar program, SSR, and strengthen its capabilities in biologics development and commercialization. If approved, SPD8 could provide an additional treatment option for patients with osteoporosis and potentially contribute to broader access to established biologic therapies. The company’s next priorities include supporting the Japanese regulatory review, preparing for the potential commercial launch and progressing regulatory strategies in other markets. The Japanese submission of SPD8 represents an important milestone in GlycoNex’s pharmaceutical development pipeline. With positive Phase III results and a marketing authorization application now submitted, the company has advanced its denosumab biosimilar toward potential regulatory approval. The outcome of the PMDA review and future commercialization partnerships will determine the next stage of the program.
Source: GlycoNex press release
