Brain disease specialist Denali Therapeutics will buy all outstanding shares in British F-Star Gamma Ltd from F-Star instead licencing bispecific antibody candidates that can cross the blood-brain barrier (BBB) co-developed under an agreement dating back to 2016.
With the exercise of the acquisition option, Denali secures F-Star Gamma’s modular (bi-specific) antibody technology. The company’s Fcabs incorporate a binding site on the constant Fc region of the antibody able to bind to BBB shuttle receptors such as transferrin (CD71). Under the 2016 agreement, F-Star Gamma has developed undisclosed preclinical Fcabs and received milestones of US$16m. Fcabs are as stable as mABs and as easy to purify as mABs because the two antibody halves (Fab fragments) do not tend to mismatch upon purification as those of competing technologies such as CrossMabs (Roche).
The total consideration for the option exercise and expanded collaboration amounts to US$24m, plus any net cash held by F-star Gamma at closing of the transaction. The option excercise payment includes US$18m and a US$6m fee for two further BBB transporter Fcab targets nominated by Denali. In addition, Denali may make future contingent payments up to a maximum of US$447m upon the achievement of defined preclinical, clinical, regulatory and commercial milestones. There are no royalty payments on net sales from future products. Through the acquisition of F-star Gamma, Denali obtains exclusive rights to discover, develop and commercialise an unlimited number of therapeutic products enabled by F-star’s intellectual property and utilizing any of the three BBB transporter Fcab targets.
In January 2018, Denali Therapeutics and Takeda Pharmaceutical Company Limited entered into a strategic option and collaboration agreement to develop and commercialise up to three specified therapeutic product candidates for neurodegenerative diseases. These are based on Denali's Antibody Transport Vehicle technology and include transferrin receptor-specific Fcabs hat were discovered by F-star's neuro-asset company F-Star Gamma.
The merger of F-Star Gamma's and Denali’s technology allow to target not only neurodegenerative diseases but also brain cancers.
Under the 2016 agreement Denali had the options either to acquire F-star Gamma prior to the start of the first Phase I study of a compound resulting from the collaboration , or to license the co-developed bispecific antibodies.
