A Japanese biotechnology company is developing a light-activated cancer treatment that it hopes could become an alternative to some conventional procedures.
Rakuten Medical believes its photoimmunotherapy technology could eventually offer an option for patients whose treatment choices are limited, but its ambitions extend well beyond what has been established so far.
The San Diego-headquartered company is concentrating around 95% of its resources on the US market, according to CEO Minami Maeda, as it works towards a potential regulatory submission in 2028. Its approach combines a targeted drug with specialised equipment designed to activate the treatment at a tumour site.
The treatment is already approved for specific head and neck cancers in Japan, giving the company experience outside the laboratory. However, approval in one country does not establish that a treatment will work for every patient or cancer type.
In the US, Rakuten Medical still needs to complete the necessary clinical and regulatory process before its technology can be marketed for routine use.
The central question is whether the treatment can demonstrate enough benefit, with acceptable risks, to justify wider adoption. The answer will depend on clinical evidence rather than the futuristic appeal of using light to attack cancer cells.
How Rakuten Medical's Photoimmunotherapy Targets Cancer Cells
The company's approach combines a drug called Akalux with its Alluminox technology platform. The drug contains an antibody that targets the epidermal growth factor receptor (EGFR), a protein found on the surface of certain cancer cells, linked to a light-sensitive dye.
After the drug has been administered and binds to its target, doctors illuminate the affected area with red light, activating the dye. The light activates the dye, triggering a reaction designed to damage the targeted cells and cause them to die.
Because the light is directed at the treatment site, the approach is intended to localise the effect, although that does not mean surrounding healthy tissue is guaranteed to be unaffected.
The underlying research has links to the US National Cancer Institute. Japanese scientist Hisataka Kobayashi and his team were investigating ways to visualise cancer cells when they observed the potential therapeutic effect of photoimmunotherapy, according to Maeda's account to Fortune.
Maeda hopes the approach could eventually become another established option alongside surgery, radiotherapy, chemotherapy and immunotherapy. However, its potential to preserve healthy tissue or improve patients' quality of life must be assessed through clinical studies.
A targeted mechanism alone cannot establish that a treatment is safer or more effective than existing alternatives.
Rakuten Medical's Cancer Trials Reveal the Challenge Ahead
Rakuten Medical's earlier Phase 3 study compared photoimmunotherapy alone with standard care in patients with recurrent head and neck cancer who had progressed after at least two previous lines of treatment and were not eligible for surgery or radiotherapy.
The 135-patient study reported median overall survival of 15.7 months in the photoimmunotherapy group, compared with 9.6 months in the standard-care group. However, median progression-free survival was similar, at 3.2 months and 3.1 months, respectively.
Recruitment was discontinued early, and the control group had a higher dropout rate, limiting the conclusions that can be drawn from the results. The findings were presented at the 2026 American Society of Clinical Oncology meeting. The published conference abstract provides the detailed figures.
Rakuten Medical is now pursuing a separate Phase 3 trial combining its treatment with pembrolizumab, an immunotherapy drug. The study aims to enrol 412 patients with locally recurrent head and neck squamous cell carcinoma without distant metastases, comparing the combination against the current standard of care.
Overall survival is the primary measure being assessed.
The company is targeting a US Biologics License Application submission in 2028, subject to the trial results. ClinicalTrials.gov lists the study, known as ECLIPSE, as recruiting. Until the evidence from this trial and the regulatory review are complete, the proposed use in the US remains investigational.
Why Rakuten Medical Is Betting on Global Expansion
Maeda's strategy also depends on convincing hospitals to adopt unfamiliar equipment and changing established clinical practices. The company installs its Alluminox platform in hospitals without an upfront equipment charge and charges a minimal fee per use, with most of its revenue coming from sales of the associated Akalux drug, according to Fortune.
This resembles the business model used by printer manufacturers that sell hardware cheaply while earning money from consumables.
The approach could lower the initial cost of adopting the technology for hospitals, although the overall economics will depend on drug prices, treatment volumes, staffing and other clinical requirements. Maeda told Fortune that the Japanese business was profitable, while the global operation remained loss-making because of research expenditure.
The company is also looking towards markets including Taiwan, Macau, Singapore, Hong Kong and Saudi Arabia. Maeda sees Macau as a potential route towards partnerships and eventual expansion into mainland China, where local regulatory requirements would still need to be addressed.
For now, the distinction between an approved treatment and an experimental one remains central to Rakuten Medical's plans. Its technology has moved beyond initial laboratory research, but its future role in cancer care will depend on the quality of its clinical results, the patients who benefit and whether regulators conclude that the evidence supports wider use.
