Waltham, MA-based ImmunoGen (NASDAQ: IMGN) has snagged a little more than $67 million from a public offering. The cancer drug developer priced 9 million shares at $8 apiece. J.P. Morgan Securities Inc. is acting as the sole book-runner for the offering and Oppenheimer & Co. Inc., RBC Capital Markets Corporation, Cantor Fitzgerald & Co. and Morgan Joseph & Co. Inc. are acting as co-managers. ImmunoGen shares were trading at $7.96 this morning, down eight percent. ImmunoGen uses...