UCSF-based startup nabs $18M Series A for I/O in late-stage cancers

Startup Fortis has emerged from stealth mode with an $18 million Series A financing led by Avalon Ventures. Based on tech licensed from the University of California at San Francisco (UCSF), the immuno-oncology company aims to get an antibody drug conjugate (ADC) into the clinic during 2018.

The company will be based at Avalon’s San Diego, CA, biotech incubator, known as COI Pharmaceuticals. It’s specifically focused on developing ADCs for late-stage cancers including late-stage metastatic castration-resistant prostate cancer and multiple myeloma.

Fortis was founded based on tech from Dr. Bin Liu, a professor in the Department of Anesthesia at UCSF. The academic institution recently came into the public spotlight as Facebook founder Mark Zuckerberg and his wife, physician Priscilla Chan, committed to donating $3 billion to support UCSF research over the next decade.

“Dr. Liu has identified a novel and unique target for an antibody drug conjugate therapy that could help patients with prostate cancer or multiple myeloma where other treatments have failed,” said Jay Lichter, president and CEO of Fortis and COI, as well as managing director of Avalon Ventures, in a statement. Bregua, Lilly Asia Ventures, Osage University Partners and Vivo Capital joined in the round.

Its ADC targets part of the tumor immune defense shield that is highly expressed throughout tumor development. That’s unlike most existing ADC targets, which are predominately lineage markers, Fortis said.

“We have found a target that is not only over-expressed in late-stage prostate cancer but is further up-regulated under selective pressures of androgen deprivation therapy,” said Fortis and COI CSO Marc Nasoff. “This target could provide a way to attack the ubiquitous problem of androgen therapy resistance in metastatic castrate-resistant prostate cancer.”

The target receptor is highly expressed in late-stage prostate cancer and is further upregulated following standard-of-care treatment with abiraterone or enzalutamide. The genes encoding the target receptor are also part of the chromosome amplification seen in a large number of multiple myeloma patients with poor prognosis.

“While therapies like abiraterone and enzalutamide, which target the amplified androgen receptor, have significantly improved the treatment of metastatic castration-resistant prostate cancer, the vast majority of patients will develop resistance to these therapies, leading to disease progression and eventually death,” said Dr. Eric Small, who heads the company’s scientific advisory board and is the chief of the Division of Hematology and Oncology in the Department of Medicine at UCSF. “We need therapeutic options after androgen receptor-directed therapy that could substantially improve survival.”