Ambit Nabs Partnership With Astellas, $40M Upfront Cash, To Develop Leukemia Drug

Xconomy San Diego — 

Ambit Biosciences is showing that its third try to build a company looks like a charm. The San Diego-based biotech company said today it has secured a partnership with Japan-based Astellas Pharma to co-develop new drugs for cancer and other diseases.

The deal revolves around Ambit’s lead experimental drug for acute myeloid leukemia, AC220, and other undisclosed molecules from Ambit that block the FLT3 kinase. Ambit will get $40 million in upfront cash, milestones worth as much as $350 million for success in development, plus undisclosed milestone payments for reaching sales goals, and tiered double-digit percentage royalties on sales. Ambit will retain an option to co-promote AC220, in which it would split the U.S. profits equally. Development expenses will be split equally in the U.S. and Europe.

As I described in a feature story in September, Ambit drew attention from around the industry at last year’s meeting of the American Society of Hematology meeting in San Francisco. That was where researchers reported that almost one-third (16 of the first 54 patients) with relapsed forms of acute myeloid leukemia had tumor shrinkage after taking nothing but the Ambit drug. Given how sick the patients were entering the study, the results were called “very encouraging” by study investigator Jorge Cortes of M.D. Anderson Cancer Center. That was enough for AC220 to take the next step into a mid-stage clinical trial of 180 patients this month. If Ambit can duplicate those results, it could have a new option for a specific type of acute myeloid leukemia that strikes 4,000 people each year in the U.S., mostly elderly, who have a short life expectancy and no realistic treatment options beyond chemotherapy.

“We are pleased to have entered into a great partnership with Ambit,” said Masafumi Nogimori, president and chief executive officer of Astellas, in a statement. “We believe that AC220, as the most selective and advanced FLT3 kinase inhibitor, has the potential to provide a new treatment option for AML where high unmet medical needs exist.”

This represents a big step ahead for Ambit as a drug developer. The company was founded in 2000, and has scrapped a couple of previous business plans that centered on selling information about proteins to drug companies, and developing second-generation versions of aging blockbuster drugs based on better understanding of the protein targets they hit.

The ongoing clinical trial of Ambit’s lead drug candidate, AC220, will restrict enrollment to patients with a mutation of the FLT3 kinase, the specific target the Ambit drug is made to block. Ambit and Astellas will also collaborate on research and development of other FLT3 inhibitors for treating cancer and other diseases.