NEW YORK – Boundless Bio on Tuesday said it closed a $100 million Series C financing round and will use the funds to develop its extrachromosomal DNA (ecDNA)-directed therapy BBI-355 through Phase I/II trials in patients with oncogene-amplified cancers.
The financing was co-led by Leaps by Bayer and RA Capital Management and included new investors Sectoral Asset Management and Piper Heartland Healthcare Capital. Existing investors Fidelity Management and Research, ARCH Venture Partners, Nextech Invest, Wellington Management, Vertex Ventures, and others also participated.
The raised funds will support the ongoing POTENTIATE trial, in which Boundless researchers are determining safety, the maximum-tolerated dose, and a recommended Phase II dose of BBI-355, a selective checkpoint kinase 1 (CHK1) inhibitor. The study involves patients with metastatic non-resectable solid tumors harboring oncogene amplifications and who have progressed on or are out of standard treatment options.
About 14 percent of patients with early-stage cancers and up to 40 percent of those with metastatic cancers have ecDNA, which is absent in healthy tissue. Boundless estimates that up to 400,000 newly diagnosed cancer patients in the US each year could benefit from ecDNA-directed therapies.
The financing will also support advancement of the San Diego-based company's preclinical ecDNA-directed therapeutic candidates and an ecDNA diagnostic Boundless is developing with Sophia Genetics to identify clinical trial participants who have cancers with ecDNA.
In parallel with the financing, Boundless said that Fabio Pucci, senior director of Venture Investments Health at Leaps by Bayer, will join its board of directors.