STELLA PHARMA CORPORATION
4888・Growth Market・Pharmaceuticals
Business
STELLA PHARMA is a single-segment pharmaceutical development company whose only product is Steboronine®, a boron agent for Boron Neutron Capture Therapy (BNCT). In March 2020, the company obtained the world's first manufacturing and marketing approval for a BNCT pharmaceutical, indicated for unresectable locally advanced or locally recurrent head and neck cancer, and began sales in May of the same year. Domestically, BNCT treatment is being conducted at two facilities—Southern TOHOKU General Hospital and Osaka Medical and Pharmaceutical University Hospital—generating revenue through a direct sales model via pharmaceutical wholesalers. The company is pursuing global BNCT adoption through expansion of indicated diseases (completion of approval applications for recurrent meningioma and angiosarcoma), overseas expansion into China's Hainan Island, and a partnership with TAE LIFE SCIENCES in the US and Europe.
Business Model
Steboronine® functions as a combination product with BNCT treatment systems installed by accelerator manufacturers (such as Sumitomo Heavy Industries, Ltd.). In Japan, the company employs a self-distribution model, selling to medical institutions via a pharmaceutical wholesaler (SD Collabo Co., Ltd.). Overseas, the company plans supply through partnerships with local partner companies (an alliance model), and in Hainan, China, monetization through direct export has already begun. The structure is such that expanding the installed base of accelerators directly drives growth in case numbers and sales, with the partnership agreement with Sumitomo Heavy Industries, Ltd. holding the key to expanding domestic facilities.
Company Strengths
Obtained manufacturing and marketing approval from the Ministry of Health, Labour and Welfare in March 2020 as the world's first boron agent for BNCT. It has also been designated under the SAKIGAKE Designation System, and since designation under this system requires the drug to be groundbreaking, this functions as a barrier to entry for follow-on entrants. The years of R&D required and the substantial accumulated investment also constitute high barriers for follow-on entrants.
The enrichment technology for high-purity (99% or higher) B-10, the raw material used, is held solely in Japan and by only two companies worldwide. The company has entered into an exclusive trading agreement with Stella Chemifa for a 10-year period from the date of obtaining pharmaceutical manufacturing and marketing approval, securing a stable raw material procurement structure. It has also obtained multiple patents related to formulation, aiming to maintain its competitive advantage.
Completed marketing approval applications in March 2026 for recurrent meningioma (progression-free survival of 14.4 months versus 1.4 months, a statistically significant difference) and angiosarcoma (response rate of 50.0%). Both indications have already received orphan drug designation and are subject to priority review. A Phase I/II trial for thoracic malignancies is also underway, having received a subsidy award of up to approximately ¥280 million from AMED.
ENVALITH's Perspective
Performance Trend
Revenue for FY2026 (ending March 2026) was ¥323 million (down ¥638 million from ¥961 million in the prior period), the operating loss was ¥749 million (widening ¥659 million from a loss of ¥90 million in the prior period), and net loss for the period was ¥781 million. The main cause was the absence in the current period of overseas sales (to China and elsewhere) that had been recorded in the prior period. SG&A expenses increased to ¥1,028 million (from ¥936 million in the prior period), widening the loss. Total assets decreased to ¥4,487 million (from ¥5,417 million in the prior period), and net assets decreased to ¥2,427 million (from ¥3,207 million). The equity ratio was 54.1% (down from 59.2% in the prior period). The period-end balance of cash and cash equivalents was ¥2,778 million (down from ¥3,161 million in the prior period). Looking at the trend over the past five periods, revenue of ¥961 million in FY2025 (ended March 2025) stood out, and FY2026 (ending March 2026) shows a pronounced reactionary decline from that level. For FY2027 (ending March 2027), revenue of ¥1,038 million is forecast on the back of the resumption of exports to China and an increase in domestic cases, but an operating loss of ¥696 million is expected to continue.
Growth Strategy
Pursuing BNCT market expansion along three axes: indication expansion, overseas expansion, and manufacturing system reconstruction
Completed partial change applications for manufacturing and marketing approval for both diseases in March 2026. Recurrent meningioma has received priority review designation evaluation from the PMDA, and approval is expected to be obtained within a shorter review period than usual. Approval acquisition is expected to expand the target patient population and increase domestic sales.
The Pengbo (Hainan) BNCT Center opened in February 2026, and the first treatment for a head and neck cancer patient was conducted on March 19. Real-world clinical data can also be used for approval applications in mainland China. Full-scale booking of export sales to China is incorporated into the earnings forecast for FY2027 (ending March 2027).
Following the quasi-bankruptcy filing of the main manufacturing subcontractor in September 2025, a development and manufacturing outsourcing agreement was concluded with a new domestic manufacturing subcontractor in October 2025. Trial production at the pilot plant was completed by the end of December 2025. The company aims to obtain approval for the change of manufacturing site around January 2027, following commercial plant manufacturing trials, process validation, and stability testing.
The first patient in the clinical trial was enrolled in April 2025. The trial, conducted in collaboration with the National Cancer Center, Sumitomo Heavy Industries, and CICS, is the world's first BNCT trial targeting multiple thoracic cancers. It was selected for a subsidy of up to approximately ¥280 million under AMED's FY2026 (Reiwa 8) program (April 2026 to March 2029). The trial period is scheduled to run through October 2028.
The company is providing the investigational drug free of charge in cooperation with a randomized, open-label comparative trial for recurrent malignant glioma conducted by Osaka Medical and Pharmaceutical University (selected for AMED's FY2025 (Reiwa 7) Innovative Cancer Medical Practical Application Research Program). The development policy has been changed to aim for an approval application based on the trial data. For newly diagnosed glioblastoma, the company is cooperating with a Phase I investigator-initiated trial at the University of Tsukuba.
An equity program agreement was concluded with CVI Investments, Inc. in March 2026. Payment for 1,000,000 new shares (¥696 million) was completed on April 16, 2026, and stock acquisition rights (5th series, 1,050,000 potential shares, exercise price ¥908) have also been issued. The funds raised are planned to be allocated to rare cancer clinical trials, research and development, overseas expansion, and the establishment of a stable supply system.
Last updated: July 19, 2026