Cidara Therapeutics, Inc. announced that it has selected its first oncology drug-Fc conjugate (DFC) candidate from the company's Cloudbreak® platform: CBO-212, targeting CD73. CBO-212 targets CD73, which contributes to immune evasion in solid cancers by flooding the microenvironment surrounding tumors with adenosine, a potent immune cell suppressor. CD73 is highly expressed on a variety of tumor and stromal cells as well as immunosuppressive cell populations such as regulatory T cells and myeloid-derived suppressor cells.

CBO-212 is designed to address the potency, efficacy, pharmacokinetic and safety limitations of small molecule and monoclonal antibody candidates targeting CD73. Cloudbreak DFCs stably couple highly potent small molecules or peptides to a proprietary variant of a human antibody fragment (Fc). As a result, DFCs are long-acting, and are designed to directly inhibit specific disease targets.

DFCs can be tuned to engage the immune system or to be immune silent, expanding the breadth of indications that can be targeted. Immune active DFCs can attract an immune response against cancer cells to maximize disease eradicating activity, while immune silent DFCs allow for expansion into cancer indications where immune system engagement would result in host toxicity.