Property developer Lang Walker's biotechnology investment secrets

Lang Walker reckons he is yet to have his greatest success investing in biotechnology companies, but he has no problem identifying his biggest failure: the $10 million he lost backing a novel pain-relief drug.

The demise of QRxPharma in 2014 pitted Walker and his ally, fund manager Allan Gray, against a board with biotechnology royalty including ResMed chairman Peter Farrell and venture capitalist Michael Quinn.