Synthorx’s Shawver Joins Silverback Therapeutics as New Top Exec

Xconomy Seattle — 

Veteran biotech executive Laura Shawver is taking over as CEO at Silverback Therapeutics, joining the cancer drug developer as it is poised to move its first compound into the clinic.

The Wednesday announcement comes three months after French firm Sanofi (NYSE: SNY) closed its $2.5 billion acquisition of La Jolla, CA-based Synthorx, the biotech Shawver most recently headed.

At Seattle-based Silverback, Shawver steps into a role previously held by co-founder Peter Thompson, an OrbiMed partner who, with others, launched the company in 2016.

Shawver has known Thompson for about a decade. New York-based OrbiMed led Synthorx’s $63 million Series C financing round. Thompson also co-founded Burlingame, CA-based Cleave Biosciences, another cancer drug developer, where she served as CEO moving to head Synthorx.

In talks with Thompson, “we both appreciated that there has to be a way to treat patients beyond the [chimeric antigen receptor] T cell therapies, because while T cell therapies have certainly been a major advancement in our area for cancer patients, especially advanced cancer patients, the reality is that for the vast majority of cancer patients, these don’t work, and we need to find a new way,” Shawver said in a phone interview.

Silverback’s approach uses its ImmunoTAC platform to create drugs that can be administered systemically but act locally, avoiding the toxicities associated with molecules that attack healthy cells as well as cancer cells.

This quarter the company plans ask the FDA for permission to move into the clinic its most advanced therapeutic candidate, SBT6050, which is designed to target solid tumors that overexpress human epidermal growth factor receptor 2 (HER2). The drug candidate links an anti-HER2 antibody with a molecule that activates TLR8, a receptor expressed on myeloid cells, in an effort to prompt those cells to attack tumor cells.

Shawver said the timeline for starting human tests of SBT6050 hasn’t been affected by the COVID-19 outbreak, although it’s possible the trial could be impacted by some of the issues that have prompted many companies to put studies on hold, such as the logistical difficulties imposed by social distancing regulations. (Her timeline, however, has: Shawver plans to relocate to Seattle, but the pandemic has pushed that move to an undetermined future date.)

Silverback has raised more than $125 million in venture capital since inception, including a $78.5 million Series B financing round last month.