— Real-World Evidence Evaluating the Association Between Treatment Procedures and Effectiveness and Safety —
Disclaimer: Rakuten Medical’s Alluminox® platform-based photoimmunotherapy is investigational outside Japan.
San Diego, California – July 30, 2026 – Rakuten Medical, Inc., a global biotechnology company developing and commercializing precision, cell-targeting Alluminox® platform-based photoimmunotherapy (PIT), today announced that new data evaluating treatment procedures to optimize ASP-1929 photoimmunotherapy was presented at the American Head & Neck Society 12th International Conference on Head and Neck Cancer (AHNS 2026) in Boston, Massachusetts, USA.
The poster reports findings from an exploratory analysis of the open-label observational study, ASP-1929-401 (jRCT1041210120), which assessed the impact of ASP-1929 PIT procedure on effectiveness and safety in patients with unresectable, locally advanced or recurrent head and neck cancer.
The poster presenter, Dr. Nobuhiro Hanai, Deputy Director and Chief of the Department of Head and Neck Surgery, Aichi Cancer Center in Japan, who serves as the principal investigator of this study, commented:
“Photoimmunotherapy was first approved and launched as a reimbursed treatment in Japan for head and neck cancer, and over the past five years, we have accumulated valuable real-world clinical experience. This study suggests that treatment procedures may influence clinical outcomes, offering important insights for optimizing clinical practice. We hope these findings will help inform future clinical research not only in Japan, but also globally and across other cancer types”
Overview of the poster presentation at AHNS 2026
Title: Investigation of Treatment Procedure to Optimize Photoimmunotherapy for Head and Neck Cancer
Presenter: Dr. Nobuhiro Hanai (Aichi Cancer Center in Japan)
Poster: View/Download Poster [PDF]
Poster number: P224
Key findings:
- Effectiveness
To evaluate the effective illumination range, lesion-based effectiveness based on tumor volume reduction was compared using two different illumination settings: (1) the initial assumption of Frontal Diffuser (FD): 10 mm depth; Cylindrical Diffuser (CD): 10 mm radius with (2) a refined hypothesis informed by physicians’ clinical experience FD: 5 mm depth; CD: 7 mm radius.The outcomes were compared between lesions in which the entire tumor was completely covered during every laser illumination session and lesions in which tumor coverage was incomplete during at least one illumination session.
Under Setting (1), volume-based complete response (v-CR) rates was 42.9%, and a favorable trend in tumor response* was observed. Under Setting (2), v-CR rate was 58.6%, and tumor response* was significantly improved (p=0.0065).
These findings suggest that more favorable antitumor effects may be achieved when laser illumination sufficiently covers the entire tumor and when a narrower effective illumination range is applied.
Effective illumination range
Reference: AHNS 2026 Immunotherapy / Systemic Therapy P224
- Safety
Both predictable and difficult-to-predict cases were observed with respect to the risk of treatment-related adverse events (TRAEs) such as severe bleeding, airway obstruction and fistula, or functional loss. These findings underscore the importance of careful treatment planning, including thorough assessment of the relationship between the tumor and surrounding anatomical structures, to minimize the risk of such events. Furthermore, because pre-treatment imaging alone may not predict severe TRAEs in all cases, thorough assessment and appropriate patient risk communication are also essential.
*Tumor response refers to the lesion-based response (Complete response: CR, partial response: PR, stable disease: SD, and progressive disease: PD).
Background
Photoimmunotherapy using ASP-1929 (cetuximab sarotalocan sodium) is a drug–device combination therapy targeting epidermal growth factor receptor (EGFR)-expressing tumor cells, activated by localized illumination with 690 nm red light.
Clinical studies1,2 of ASP-1929 PIT in head and neck cancer have shown meaningful antitumor activity and a manageable safety profile. In Japan, the drug, Akalux™ (ASP-1929) and medical device, BioBlade™ Laser System for the treatment of unresectable locally advanced or recurrent head and neck cancer were approved in 2020. Outside of Japan, ASP-1929 has not yet been approved for commercial use by any regulatory authority.
In ASP-1929-401 study, primary endpoint results showed an overall response rate (ORR) of 60.8% and a disease control rate (DCR) of 95.9% per laser-illuminated lesion3. Additionally, results from a secondary endpoint indicated a safety profile consistent with previous studies3.
As a key exploratory endpoint, the study evaluated the impact of PIT procedures on effectiveness and safety, including the association between complete tumor coverage and effectiveness under two effective illumination range assumptions, and whether pre-treatment imaging could predict the risk of serious TRAEs and functional impairments.
Study Overview
ASP-1929-401 is an open-label observational study enrolled 77 patients from 24 centers between January 2021 and September 2022.
Endpoints:
- Primary endpoint: Antitumor effect per laser-illuminated lesion, measured by tumor volume reduction rate
- Key secondary endpoint: Incidence of treatment-related adverse events
- Key exploratory endpoint: Impact of PIT procedures on effectiveness and safety
Data Review Board evaluated tumor coverage based on the effective illumination range and risks of interest under outcome-blinded assessment.
About ASP-1929
Rakuten Medical’s first pipeline drug developed on its Alluminox® platform is ASP-1929, an antibody-dye conjugate comprised of the anti-EGFR antibody cetuximab and IRDye® 700DX, a light activatable dye. ASP-1929 binds to epidermal growth factor receptor (EGFR), a cancer antigen expressed in multiple types of solid tumors, including head and neck, breast, lung, colorectal, prostate and pancreatic cancers. After binding to cancer cells, ASP-1929 is locally activated by illumination with red light (690 nm), emitted by a laser device system to produce a photochemical reaction. This reaction is believed to cause damage to the membrane of cancer cells, leading to selective necrosis of cancer cells. In Japan, ASP-1929 received marketing approval from the Japanese Ministry of Health, Labor, and Welfare for unresectable locally advanced or recurrent head and neck cancer in September 2020, under the Sakigake Designation System and the Conditional Early Approval System. ASP-1929 photoimmunotherapy in combination with pembrolizumab is currently under investigation in a global Phase 3 clinical trial as a first-line therapy for recurrent head and neck cancer. Outside Japan, ASP-1929 has not yet been approved for commercial use by any regulatory authority.
About Alluminox® platform
The Alluminox® platform is a Rakuten Medical’s investigational technology platform that combines pharmaceuticals, medical devices, medical technology, and other peripheral technologies. Rakuten Medical is developing Alluminox platform-based photoimmunotherapy, which involves two key steps: 1) drug administration and 2) targeted illumination using medical devices. The drug component consists of a cell-targeting moiety conjugated to a light-activatable dye, such as IRDye® 700DX (IR700), that selectively binds the surface of targeted cells, such as tumor cells. The device component consists of a light source that locally illuminates the targeted cells with red light (690nm) to transiently activate the drug. Rakuten Medical’s pre-clinical data have shown that this activation elicits rapid and selective necrosis of targeted cells through a biophysical process that compromises the membrane integrity of the targeted cells. Therapies developed on the Alluminox platform may also result in local and systemic innate and adaptive immune activation due to immunogenic cell death of the targeted tumor cells and/or the removal of targeted immunosuppressive cells within the tumor microenvironment. Photoimmunotherapy was originally developed by Dr. Hisataka Kobayashi and team from the National Cancer Institute in the United States. Outside Japan, Rakuten Medical’s Alluminox platform-based photoimmunotherapy is investigational.
About Rakuten Medical, Inc.
Rakuten Medical, Inc. is a global biotechnology company developing and commercializing precision, cell-targeting Alluminox® platform-based photoimmunotherapy, which, in pre-clinical studies, has been shown to induce rapid and selective cell killing. Rakuten Medical’s photoimmunotherapy is currently investigational outside Japan. Rakuten Medical is committed to its mission to conquer cancer by developing its pioneering treatments as quickly as possible to as many patients as possible all over the world. The company has offices in 5 countries/regions, including the United States, where it is headquartered, Japan, Taiwan, Switzerland and India. For more information, visit www.rakuten-med.com.
Forward Looking Statements
This press release contains forward looking statements that correspond to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. These statements include various risks, uncertainties, and assumptions that may cause Rakuten Medical’s business plans and results to differ from the anticipated results and expectations expressed in these statements. These “forward looking statements” contain information about the status and development of our products, including the Alluminox® platform, as well as other regulatory and marketing authorization efforts, the potential benefits, efficacy, and safety of therapies created using the Alluminox platform, and the status of regulatory filings. The approval and commercial success of the product may not be achieved. Forward looking statements relate to the potential benefits, efficacy, and safety of our therapies, and the status of regulatory filings. Such statements may include words such as “expect,” “believe,” “hope,” “estimate,” “looks as though,” “anticipate,” “intend,” “may,” “suggest,” “plan,” “strategy,” “will,” and “do”, and are based on our current beliefs. In addition, this press release uses terms such as “important,” “notable,” and “abnormal” to express opinions about clinical trial data. Ongoing clinical trial studies include various risks and uncertainties, in particular, problems that arise during the manufacturing stage of our therapies, the occurrence of adverse safety events, situations in failure to demonstrate therapeutic benefits, and other various risks and uncertainties, both reasonable and unreasonable. For this reason, actual results, including regulatory approvals and uncertainties in the commercialization process of our therapies, may differ from published information. Except to the extent required by applicable law, we undertake no obligation to publicly update this or any other forward-looking statement, whether because of new information, future developments or events, changes in assumptions, changes in the factors affecting forward-looking statements. If one or more forward-looking statement(s) is updated, no inference should be drawn that additional updates will be made to those or other forward-looking statements.
References:
- Cognetti DM et al. Head Neck. 2021;43:3875–87
- Tahara M et al. Int J Clin Oncol. 2021;26:1812–21
- Shinozaki T et al. Lesion-Based Analysis of Efficacy and Safety in a Multicenter Observational Study of Photoimmunotherapy for Head and Neck Cancer. The 34th Annual Meeting of the Japan Society for Head and Neck Surgery, Tokyo, Japan, Jan 2025
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