Firefly emerges with $94m to develop antibody conjugates

According to the San Francisco-based firm, its focus is on the development of DACs, which represent amalgamation of antibody drug conjugates (ADCs) and protein degraders to treat cancer.  

“DACs are a new modality for cancer,” said Scott Hirsch, CEO of Firefly. “They give us the ability to hit biologically validated targets with minimal collateral damage. Our platform enables DACs at scale and vastly expands the number of payloads for ADCs.”

According to the firm, both ADCs and protein degraders are important, but have several limitations including “limited therapeutic index due to their broadly cytotoxic payloads”, and “lack the ability to knock down specific intracellular proteins.” 

Whereas protein degraders “struggle with bioavailability and do not have the ability for cell-specific targeting.” 

Firefly aims to work on the strength of ADCs and protein degraders through its Firelink linker technology platform. Using potent catalytic protein degraders as the payloads of ADCs, the platform combines these modalities, decreasing free payload in circulation and minimizing uptake in healthy cells. Thus, reducing the dosage and optimal outputs. 

The firm claims that a single dose of its DACs has shown “significant reductions” in both solid and liquid tumors during preclinical studies. 

“At Firefly, we’ve assembled a unique talent base and platform to significantly advance this promising field,” said Jerel Davis, board member at Firefly. “The company has made rapid progress and is poised to become the leader in discovering clinically meaningful DACs in oncology and immunology.” 

The financing was led by Versant Ventures, and MPM BioImpact along with Decheng Capital and Eli Lilly & Company.  

Firefly did not respond when contacted by this publication.