ImmunoGen, Inc. Announces Webcast of Presentations at Upcoming Investor Conferences

ImmunoGen, Inc. (Nasdaq: IMGN), a biotechnology company that develops novel anticancer therapeutics using its antibody-drug conjugate (ADC) technology, today announced that the following presentations by Company management at upcoming investor conferences will be webcast:

• Credit Suisse Antibody Day 2015
• Jefferies 2015 Global Healthcare Conference

Scheduling information and the webcasts will be accessible through the “Investors” section of the Company’s website, www.immunogen.com. Webcast replay will be available at the same location for approximately a week following the conference presentation date.

About ImmunoGen, Inc.

ImmunoGen, Inc. develops targeted anticancer therapeutics. The Company’s ADC technology uses tumor-targeting antibodies to deliver an ImmunoGen cell-killing agent specifically to cancer cells. The Company utilizes its ADC technology with its antibodies to create ImmunoGen product candidates and also out-licenses limited rights to use its technology to other companies. Roche’s Kadcyla® is the first marketed product with ImmunoGen’s ADC technology. More information about the Company can be found at www.immunogen.com.

Kadcyla® is a registered trademark of Genentech, a member of the Roche Group.

For Investors:ImmunoGen, Inc.Carol Hausner, [e-mail] Media:Pure Communications, Inc.Dan Budwick, 973-271-6085