Flu treatment developer Gemmus Pharma Inc. raised about $1.5 million in a Series A funding led by a syndicate of angel investor groups.

Gemmus, housed in the Mission Bay Innovation Center in the FibroGen building in San Francisco, is targeting a receptor that plays a role in the anti-inflammatory response to viral infections. That approach, the company says, makes it so its treatment isn’t susceptible to viral resistance.

A Gemmus spokeswoman said the company initially sought to raise at least $1.2 million.

The round was led by the Life Science Angels and included BlueTree Allied Angels, Tech Coast Angels, Wilmington Investor Network and The Angels Forum.