Ajax Raises $95 Million to Advance First-in-Class Type II JAK2 Inhibitor for Myelofibrosis into the Clinic

Rare Daily Staff

Ajax Therapeutics closed an oversubscribed $95 million series C financing that will be used to support the clinical development of the company’s first-in-class Type II JAK2 inhibitor, AJ1‑11095, for the treatment of myelofibrosis, as well as advancing the company’s pipeline of treatments for myeloproliferative neoplasms.

Goldman Sachs Alternatives led the financing with participation by Eli Lilly, Vivo Capital, RA Capital Management, Point72, and existing investors EcoR1 Capital, Boxer Capital, Schrödinger, and Inning One Ventures.

“We are now well positioned to bring much needed innovation to the field of JAK inhibitors for the treatment of MPNs and look forward to advancing AJ1‑11095 into the clinic for myelofibrosis later this year.” said Martin Vogelbaum, co-founder and CEO of Ajax Therapeutics.

AJ1-11095 was designed by Ajax, through its collaboration with Schrödinger, using structure-based drug design and computational methods at scale, to selectively bind the Type II conformation of the JAK2 kinase and to provide greater efficacy with disease modification compared to all currently approved JAK2 inhibitors which bind the Type I conformation of JAK2.  Additionally, AJ1-11095 has been shown in preclinical studies to maintain efficacy against MPN cells that become resistant to chronic Type I JAK2 inhibition.

Ajax just received U.S. Food and Drug Administration clearance for its application to initiate a phase 1clinical study of AJ1‑11095 for the treatment of patients with the rare blood cancer myelofibrosis.

Myelofibrosis (MF) is characterized by spleen enlargement, scarring (fibrosis) in the bone marrow, progressive anemia, and debilitating symptoms, such as fatigue, night sweats, itching, and abdominal discomfort, which can impair a patient’s’ quality of life. The most widely used treatment for MF patients are Type I JAK2 inhibitors which can reduce spleen size and provide symptomatic improvement but have little effect on the underlying cause of disease. Over time, most MF patients stop Type I JAK2 inhibitor therapy. The most common causes for treatment discontinuation include a lack of benefit or loss of response, adverse events, and disease progression, leaving significant unmet treatment needs for these patients.

“This financing reinforces the value of Ajax’s approach to inhibiting JAK2 with its Type II inhibitor, AJ1-11095,” said Ross Levine, Ajax co-founder and chair of Ajax’s Scientific Advisory Board, senior vice president for MH Translational Research and member of the Human Oncology and Pathogenesis Program at Memorial Sloan Kettering Cancer Center. “My lab has been studying Type II inhibition of JAK2 for over 10 years and we believe AJ1-11095 possesses the unique therapeutic properties and disease modifying effects of a highly selective and potent Type II JAK2 inhibitor and we’re excited to bring it to patients with MF.”