The Dolaflexin platform was designed to increase the efficacy, safety, and tolerability of ADCs. We believe this platform overcomes the limitations of traditional ADCs in which drugs are directly conjugated to antibodies. Dolaflexin utilizes our proprietary Fleximer polymer, a biodegradable, highly biocompatible, water-soluble polymer able to carry multiple drug molecules. Instead of direct conjugation to an antibody, drug molecules are attached through an optimized, cleavable linker to the Fleximer scaffold, which is then conjugated to the antibody through a non-cleavable linker. Fleximer dramatically improves drug solubility, pharmacokinetics, and immunogenicity, and significantly increases the number of drug molecules carried by each ADC.
Our lead asset, upifitamab rilsodotin (UpRi), is a first-in-class Dolaflexin ADC targeting NaPi2b that is being studied in UPLIFT, a single-arm registrational trial in patients with platinum-resistant ovarian cancer; UPGRADE-A, a Phase 1 trial evaluating UpRi in combination with carboplatin; and UP-NEXT, a Phase 3 clinical trial of UpRi as monotherapy maintenance following treatment with platinum doublets in recurrent platinum-sensitive ovarian cancer.