Organization Description
Therini Bio is a clinical-stage biotech company developing immunotherapies that target vascular dysfunction caused by fibrin deposits as an approach for Alzheimer’s and Diabetic Macular Edema (DME).
Therini is a Venture Lab company of Apollo Health Ventures. Its scientific founder is Dr. Katerina Akassoglou.
When a blood vessel is damaged, it attracts platelets to the site of the injury, which (through a series of steps) causes soluble fibrinogen dissolved in the blood to polymerize into long, tough, insoluble strands of fibrin at the wound site. Aging, genetic risk factors, and specific diseases such as hypertension and diabetes lead to the accumulation of fibrin deposits outside of blood vessels. An inflammatory epitope on these fibrin deposits triggers innate immune cells (such as microglia in the brain and macrophages in the periphery) into a state of chronic activation. The principals of Therini believe that these hyperactive immune cells cause destructive neuroinflammation, leading to neurodegenerative diseases of the brain (Alzheimer’s disease (AD)) and retina (Diabetic Macular Edema (DME)).
THN391
Therini’s lead candidate THN391 is a monoclonal antibody that targets the inflammatory epitope on fibrin deposits outside of blood vessels. It therefore blocks the activation of microglia and macrophages, which they expect will prevent the destructive neuroinflammation and neurodegeneration that lead to these diseases, as shown in an animal model of AD.
In April 2025, Therini announced that THN391 had been found to be well-tolerated in a randomized, double-blind, placebo-controlled Phase Ia trial in healthy volunteers, with no serious or drug-related adverse events and no adverse effects on coagulation or fibrinolysis. The antibodies did not induce anti-drug antibodies, and it exhibited a pharmacokinetic profile that would enable once-monthly dosing. The following month, Therini announced that it raised $39 million in a Series A extension financing to fund a Phase Ib trial to evaluate THN391, as well as support development of a fibrin/VEGF bispecific. In July, they announced that they had dosed the first patient in a Phase Ib trial of THN391 for the treatment of Alzheimer’s.