Poseida Therapeutics Inc., a San Diego-based biotechnology company using gene editing to develop medicines, said it raised $30.5 million in a Series B round led by Longitude Capital, a health care venture capital firm in Silicon Valley.

As part of the deal, Longitude Capital managing director David Hirsch joined Poseida’s board of directors.

Also participating in the financing, which the company said was oversubscribed, were new investors Vivo Capital and the Tavistock Group and existing investor Malin Corporation plc.

Poseida said proceeds will be used to further advance its pipeline of immunotherapies and gene therapies. Its lead immunotherapy, intended to treat cases of multiple myeloma, is in Phase 1 clinical development. The California Institute for Regenerative Medicine is partially funding that study.

Poseida is a spin-off of Lexington, Ky.-based Transposagen Biopharmaceuticals.

Reach reporter Sarah de Crescenzo at sarahd@sdbj.com.