Investors have loaded Alethio Therapeutics, a U.K.-based biotechnology startup, with $90 million in funding to advance its treatments for a group of rare blood cancers, the company announced Thursday.
Alethio is diving headfirst into myeloproliferative neoplasms, a group of slow-progressing hematological malignancies that include primary myelofibrosis, essential thrombocythemia and polycythemia vera. In those conditions, the body creates too many blood cells, triggering a host of health problems such as clots, bone marrow scarring or heart attacks.
“With these patients, it's a bit like an accelerator stuck down, constant drive, no brake,” said Rohit Batta, Alethio's CEO. “But the car doesn’t crash immediately. It goes for far too long.”
Myeloproliferative neoplasms can be managed with frequent blood withdrawals, hydroxyurea, interferon therapies or “JAK” inhibitors such as Jakafi. And more recently, a new Takeda medicine, Mimrylo, was approved for polycythemia vera. But existing treatments still don’t help the majority of people with these conditions, Batta said.
Alethio’s lead program, dubbed “ATX-011,” is a monoclonal antibody Batta’s team theorizes can address those left behind, offering what the biotech says is an advantage over other entrants in a field that includes Jakafi’s maker Incyte, Merck & Co. and Novartis.
Rather than rely on what Batta calls a “blunt” approach, ATX-011 homes in on G6b, a receptor found on the surface of platelets and certain bone marrow cells. Importantly, G6b is only expressed on cells known to induce myeloproliferative neoplasms or cause bone marrow scarring, suggesting that a drug binding to the protein might have a precise impact on these diseases. Alethio believes the drug could be beneficial regardless of which disease-driving mutation patients have, too.
Preclinical studies have shown ATX-011 is “a well-behaved medicine,” Batta said. It is expected to enter clinical testing in the first half of 2028.
“The ultimate aim for ATX-011 is to allow patients to go and live their daily lives,” Batta said.
A second drug prospect, an antibody-drug conjugate, is also in development for myelofibrosis.
Alethio’s Series A funding was co-led by Sofinnova Partners and RA Capital Management, and also backed by Cancer Research Horizons, Oxford Science Enterprises and the University of Oxford. The startup spun out of research at the university, and was co-founded by Adam Mead and Beth Psaila, a pair of physicians and professors working there.
Graziano Seghezzi, a managing partner at Sofinnova Partners, said Alethio’s decision to target essential thrombocythemia could give its drug greater “reach” compared to approved treatments for other myeloproliferative neoplasms. Essential thrombocythemia affects an estimated 150,000 patients in the U.S., according to Alethio, more than the combined amounts believed to have polycythemia vera and primary myelofibrosis.
“The key words are we're not controlling the disease, we're treating it,” Seghezzi said.
