
Flush with cash, Rakuten billionaire Mickey Mikitani looks to take his photoimmunotherapy platform global
E-tailer billionaire Mickey Mikitani has backed Aspyrian Therapeutics’ photoimmunotherapy tech from the beginning, starting as a participant in the company’s $40 million Series A round and later taking the helm as CEO and wrapping the brand entirely into his Rakuten empire.
He’s now reeled in another $166 million to push the company’s lead head and neck cancer drug through a global Phase III trial.
Rakuten Medical — formerly known as Aspyrian Therapeutics, then Rakuten Aspyrian — unveiled a Series D round on Wednesday, consisting of $75 million in new capital and $91 million in convertible promissory notes. General Catalyst led the round, with some help from existing investors like Rakuten Group and SBI Group.
“We believe the extensibility of the Illuminox platform has the potential to redefine the way clinicians care for their patients,” Paul Kwan, managing director at General Catalyst, said in a statement.
The California-based biotech’s Illuminox platform is based on photoimmunotherapy work from the lab of Hisataka Kobayashi at the National Cancer Institute. Kobayashi, an imaging expert, made the somewhat serendipitous discovery that conjugating an antibody with a light-activated dye called IRDye 700DX, then hitting it with a near-infrared light, could kill cancer cells without off-target toxicity.
Mikitani stumbled upon the discovery while searching for a better therapy for his father, who was dying of pancreatic cancer. While it was too late to save his father, he ran with the idea, backing Aspyrian and then taking the CEO spot in 2018.
Rakuten’s lead candidate, ASP-1929, was granted conditional early approval in Japan for advanced or locally recurrent head and neck cancer in September, and is currently in a global Phase III trial for the same indication. The candidate employs the antibody cetuximab conjugated to IRDye 700DX, and is designed to bind to epidermal growth factor receptors (EGF), which are expressed in several types of solid tumors, including head and neck, cutaneous esophageal, lung, colon and pancreatic cancers. Then it’s locally activated by a laser device system.
Rakuten says it’s working on additional therapies under the same platform to treat “a range of oncological indications.” The company is also investigating ASP-1929’s efficacy in combination with anti-PD1 in multiple tumor types, including head and neck cancer.