The concept of a parent company with operating subsidiaries is becoming increasing common in biotech. The first to do it, Daphne Zohar, who co-founded PureTech back in 2005, tells Scrip how the company has made that model work.

Daphne Zohar tells Scrip PureTech will use $100m placing to develop Boston-based group's growth-stage affiliates and advance its "BIG" proprietary pipeline of brain-immune-gut assets.

Investments for start-ups seeking their first infusion of venture capital continues to be scarce as venture firms seek later-stage opportunities and liquidity to improve their own chances of raising new funds.