Soricimed is using its knowledge of TRPV6-targeting peptides to develop next generation peptide-drug conjugates for cancer treatment. Potent cancer-killing drugs used in cancer treatment do not discriminate tumour tissue from healthy tissue resulting in a narrow therapeutic window and severe toxicities. To overcome these limitations, we link these highly potent cytotoxic payloads to peptides that target TRPV6 and deliver the payload quickly and directly to the tumor. As a result, the cancer drug rapidly accumulates in the tumour and spares healthy tissue from exposure to these toxic agents. We are currently investigating several TRPV6-targeting peptide-drug conjugates that have shown very encouraging tumor responses in animal cancer models. We plan to elect a lead drug candidate in 2018.
Our peptide-drug conjugate (PDC) approach has several advantages over other drug conjugate programs like antibody-drug conjugates (ADCs). As opposed to ADCs our PDCs are much smaller, have better tumour penetration, lower systemic exposure, less risk of liver damage and are easier and cheaper to manufacture.
One of our more advanced PDCs, SBI-1301, has shown complete tumour regression for more than 60 days with just 3 treatments during the first 12 days in mice with prostate cancer xenografts.
Early in vitro work with a peptide-paclitaxel conjugate provided encouraging evidence for efficacy and allowed a presentation of PDC results at the World ADC conference in San Francisco, 2013 . An in vivo follow-up study showed this PDC had better efficacy than either paclitaxel alone or a mixture of peptide and paclitaxel in PC3 (prostate cancer) xenografts.
One of our more advanced PDCs, SBI-1301, a conjugate of an extremely potent cytotoxic agent, has shown complete tumour regression with just 3 treatments over 12 days in prostate cancers xenografted in mice. At the highest doses tested there were no obvious toxic symptoms. The mice were observed for 60 days and the tumors did not re-grow.
Inhibits Cancer Cell Growth at Nanomolar IC50 Concentrations
Cancer cells were implanted under the skin and allowed to grow for 24 days
We are currently evaluating several TRPV6-targeting peptide-drug conjugates and plan to elect a lead candidate for development in 2018.