Immusoft CEO Sean Ainsworth. (Immusoft Photo)

Seattle-based biotech startup Immusoft this week closed a $20 million Series B venture capital round that will fuel development of its gene therapy technology.

Founded in 2009, Immusoft develops immune cell technology that uses blood cells from a patient to create therapeutic proteins targeted to treat diseases.

The process is called immune system programming, or ISP, and was invented by Nobel laureate David Baltimore in 2006. Immusoft has been expanding on the technology and developing treatments based on it that use special enzymes and proteins to treat HIV, muscle loss, and other diseases.

“Throughout 2018, the Immusoft team made extraordinary progress advancing our ISP platform. This is highlighted by our lead candidate, ISP-001, receiving both orphan drug and rare pediatric disease designations from the FDA,” Immusoft CEO Sean Ainsworth said in a statement. “With the closing of our Series B financing, we believe we are now strongly positioned to advance this novel approach for treating MPS I patients through Phase I/II clinical development with the goal of generating initial safety and potential efficacy data during 2019.”

The technology works by inserting functional genes into immune cells, with the modified cells operating in the body and secreting gene-encoded proteins.

“The platform’s broad utility to produce virtually any biologic drug entity (e.g. antibodies, proteins or enzymes), has the potential to disrupt the current standard of care for many diseases requiring recombinant enzyme replacement therapy, as well as, address rare orphan diseases,” the company wrote in its press release.

Ainsworth, a veteran biotech executive, joined the company a year ago as its new CEO, replacing founder and longtime CEO Matthew Scholz, who is now CTO and will retain his position on the board of directors. Ainsworth previously founded gene therapy company RetroSense Therapeutics, which sold to Allergan in 2016 in a deal worth up to $555 million.

In September, Immusoft landed a $3.5 million Phase II Small Business Innovation Research grant from the National Institute of General Medical Sciences.

Breakout Ventures, Alexandria Venture Investments, RBV Capital, DEFTA Partners, and Mesa Verde Venture Partners participated in the latest round of capital, which the company said was “oversubscribed.” Total funding to date is north of $30 million.

Like what you're reading? Subscribe to GeekWire's free newsletters to catch every headline

Job Listings on GeekWork

Find more jobs on GeekWork. Employers, post a job here.