Syntimmune Turns Drug For Rare Anemia Into $400M Alexion Buyout

Xconomy Boston — 

Syntimmune, a biotech startup formed by the veteran founders of the hemophilia drug developer Syntonix, has been acquired by Alexion Pharmaceuticals for $400 million in cash up front.

Syntimmune is right in Alexion’s (NASDAQ: ALXN) wheelhouse. The Boston-based firm is best known for eculizumab (Soliris), a drug for ultra-rare blood diseases. In buying Syntimmune, Alexion will acquire an experimental drug for a rare type of anemia, warm autoimmune hemolytic anemia (WAIHA). Beyond the upfront cash, Syntimmune’s shareholders, led by Apple Tree Partners, could see another $800 million in downstream payments if the drug progresses.

Syntimmune was formed in 2013 by brothers Laurence and Richard Blumberg, who two decades ago teamed up to form Syntonix Pharmaceuticals—a hemophilia drug developer that Biogen (NASDAQ: BIIB) acquired in 2007. Laurence was Syntimmune’s CEO and chief operating officer, and Richard is the company’s scientific founder. The brothers have remained on the company’s board, and Jean-Paul Kress has been serving as CEO. The company has offices in New York and Waltham, MA, and raised $78 million in venture financing.

Syntimmune has been developing a drug, SYNT001, that blocks the interaction of two molecules in the body—called neonatal Fc receptor (FcRn) and immunoglobulin G (IgG)—that together can cause autoimmune disease, when the body attacks itself. The FcRn-IgG relationship is implicated in several autoimmune disorders, including lupus, inflammatory bowel disease, and rheumatoid arthritis. And Syntimmune hasn’t been alone in targeting it—Momenta Pharmaceuticals (NASDAQ: MNTA), Dutch firm Argenx, Belgium’s UCB, and others are also in the mix.

Syntimmune, however, is the only one in the group with a drug in human testing targeting WAIHA. The disease occurs when the body prematurely and mistakenly destroys its own red blood cells. It affects one to three of every 100,000 people in the general population per year, according to the National Organization for Rare Disorders. There are no drugs approved specifically for WAIHA.

Syntimmune has also been studying SYNT001 in two forms of the autoimmune disease pemphigus—pemphigus vulgaris and pemphigus foliaceus—which causes dangerous blisters to form on the mouth, skin, or other parts of the body. The drug showed an ability, in an early study disclosed in May, to quickly reduce levels of IgG in the blood.

Alexion will hold a conference call this morning to discuss the deal. The buyout should close in the fourth quarter.