San Diego’s ImThera Medical has raised about $1.8 million of a planned $2 million financing round that includes both equity and rights to acquire securities, according to a recent regulatory filing. ImThera, which has been developing an implantable neurostimulation device for treating obstructive sleep apnea, says the funds will be used for the next phase of trials in the European Union, and to advance the company’s request for an investigational device exemption with the FDA in the United States. ImThera said today that clinical trial results of a European pilot study will be presented May 16 at the American Thoracic Society’s International Conference in Denver, CO.