Gregory C. Prada resigned after 18 months...

Gregory C. Prada resigned after 18 months as chief executive and a director of HemaCare, a Sherman Oaks company that sells blood products and stores blood.

Thomas M. Asher, the company’s chairman, will temporarily assume Prada’s job. HemaCare said Prada resigned to pursue personal interests. He could not be reached for comment.

In the nine months ended Sept. 30, HemaCare lost $393,000 on revenue of $2.4 million, compared to a loss of $131,000 on revenue of $2.1 million in the comparable period a year earlier. Asher attributed the loss to heavy spending to expand the company.