Northwest Biotherapeutics, of Bethesda, a biotechnology company developing DCVax treatments for solid tumor cancers, announced that the $17.5 million convertible note offering announced Thursday has closed. The three-year notes have a 5 percent interest rate and are convertible at $7.30 per share of common stock. The investors also have an option, exercisable for three months, to purchase up to an additional 30 percent of these notes on the same terms. The proceeds from this offering will help support an increase in the manufacturing capacity for the company’s DCVax products, as well as ongoing Phase III and Phase I/II clinical trials. “We are pleased to complete this convertible debt funding … to help bring on additional production capacity in Europe,” Linda Powers, CEO of NW Bio, said in a statement.