Biopharma company ImmunoGen, (NASDAQ: [[ticker:IMGN]]), of Waltham, MA, announced today that it has sold 7.8 million shares at $3.20 per share to Ziff Asset Management. ImmunoGen, which is expected to net approximately $24.7 million after expenses, has six anti-cancer drugs in clinical testing, four of them through collaborations with other pharma companies.