Emerging Company Profile: Spinning out of Versant Ventures’ Inception Sciences, San-Francisco-based development-stage biotech Tempest Therapeutics Inc. completes $70m Series B round to advance small molecules that modulate anti-tumor immunity pathways.

In this tale of two companies, it's the best of times and the best of times. J&J gets immediate value by acquiring Actelion's blockbuster PAH franchise and its late-stage pipeline, while its stake in an Actelion spinout offers longer-term potential.

Born at a time when venture capital found few exit opportunities for early-stage companies, build-to-buy helped mitigate the risk in investing in uncharted science. But the model is flourishing even in this period of wider capital options.

Versant and Celgene have partnered again to launch a build-to-buy biotech, this time focusing on inflammatory bowel disease.