Onetime T. Rowe Star Posts Big Gains Running His Own Fund

As a star fund manager at T. Rowe Price Group Inc., Henry Ellenbogen produced an annualized 19.2% return. He’s exceeding that mark at his own investment fund.

Durable Capital Partners, the firm he launched a year ago this month after exiting the fund giant, has gained more than 24% this year through October, according to people familiar with the matter.

Ellenbogen’s solo success comes in part from buying stakes in public companies directly from businesses rather than in the market, deals known as PIPEs. The firm, with $10 billion in assets, has also backed promising startups, especially in ...