ZURICH—UBS’s wealthy clients have raised $650 million for the biggest biotechnology impact fund ever, the Swiss bank said on Wednesday. Impact investing—a term coined in 2007—grew out of the desire to extend philanthropic goals into mainstream financial holdings. Alongside financial returns, impact investments aim to generate measurable environmental and social impact, often in line with the United Nations Sustainable Development Goals (SDGs), which generally go beyond the basic principles of sustainable investing. The Oncology Impact Fund 2, run by biotechnology investment firm MPM Capital, has raised a total of $850 million, including the $650 million obtained from UBS clients. It will invest 80 percent of its capital into privately held start-ups, and the remainder into public companies, developing innovative treatments for cancer and other serious illnesses. Twenty percent of the performance fee the managers earn off their investments, as well as a portion of drug royalties, will be donated to …