UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): November 26, 2018

ImmunoGen, Inc.

(Exact name of registrant as specified in its charter)

830 Winter Street, Waltham, MA 02451

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code: (781) 895-0600

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

o            Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o            Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o            Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o            Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is a an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter.

Emerging growth company o

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

ITEM 5.02 — DEPARTURE OF DIRECTORS OR CERTAIN OFFICERS; ELECTION OF DIRECTORS; APPOINTMENT OF CERTAIN OFFICERS; COMPENSATORY ARRANGEMENTS OF CERTAIN OFFICERS

On November 26, 2018, Mr. David B. Johnston, Executive Vice President of ImmunoGen, Inc. (also referred to as “we,” “our,” and “ImmunoGen”), stepped down as our principal financial officer, effective immediately.  Mr. Mark J. Enyedy, President and Chief Executive Officer, has assumed the responsibilities of principal financial officer while we engage in a search for a permanent replacement for Mr. Johnston.

On November 26, 2019, our Board approved certain transition arrangements with Mr. Johnston, which are summarized as follows:

·                  Mr. Johnston will remain a full-time employee of ImmunoGen through December 31, 2018, at which time his employment will be terminated. In connection with such termination, Mr. Johnston would be eligible for benefits under our Severance Pay Plan for Vice Presidents and Higher (the “Severance Plan”). Mr. Johnston, however, has agreed to waive his rights under the Severance Plan in connection with entering into a consulting agreement with us as described below.

·                  We will enter into a consulting agreement pursuant to which, beginning on January 1, 2019, Mr. Johnston will provide consulting and advisory services to ImmunoGen for a period of up to 12 months. In consideration of these services, and Mr. Johnston’s waiver of his rights under the Severance Plan, we have agreed to pay Mr. Johnston a quarterly retainer in the amount of $104,532.50. If Mr. Johnston elects to continue medical insurance coverage in accordance with COBRA, we also will subsidize his COBRA premium at the same percentage as the health insurance premium subsidy provided to similarly situated active employees during the term of the consulting agreement. The foregoing compensation is analogous to that which Mr. Johnston would have been entitled to under the Severance Plan.

·                  Mr. Johnston will be eligible to receive his annual cash bonus for 2018, determined in accordance with our annual bonus program, if, as, and when bonuses are paid to employees who were similarly situated to him as of year-end. This payment is analogous to what Mr. Johnston would have been entitled to under the Severance Plan.

·                  The terms of certain fully vested incentive stock options (“ISOs”) held by Mr. Johnston covering an aggregate of 32,504 shares will be modified to provide that such options will remain exercisable and continue to vest during the term of the consulting agreement. The terms of certain fully vested stock options held by Mr. Johnston covering an aggregate of 340,000 shares (inclusive of the ISOs referenced above) will be modified to provide that such options will remain exercisable for a period of 12 months following the end of the consulting arranagement. Except as described above, the terms of Mr. Johnston’s equity awards will remain unchanged.

Information regarding Mr. Enyedy can be found under Item 3.1 Executive Officers of the Registrant in our Annual Report on Form 10-K for the year ended December 31, 2017, which is available on the SEC’s website (www.sec.gov).

2

ITEM 9.01. FINANCIAL STATEMENTS AND EXHIBITS

(d): The following exhibits are being filed herewith:

3

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

4

Exhibit 99.1

ImmunoGen Announces Resignation of Chief Financial Officer

WALTHAM, Mass. — November 26, 2018 — ImmunoGen, Inc., (Nasdaq: IMGN), a leader in the expanding field of antibody-drug conjugates (ADCs) for the treatment of cancer, today announced that David B. Johnston has stepped down as Chief Financial Officer of the Company, with immediate effect. Mr. Johnston will remain employed with the Company through the end of 2018 and thereafter will serve as a consultant to provide transitional support. David Foster, Vice President of Finance and Chief Accounting Officer, will continue to oversee ImmunoGen’s Finance and Accounting functions. Mark Enyedy, President and Chief Executive Officer, will serve on an interim basis as the Company’s principal financial officer, as well as lead its Investor Relations function. A search has been initiated to identify a new Chief Financial Officer.

“We thank Dave for his many contributions to ImmunoGen over the last five years,” said Mark Enyedy. “He has built a first-rate Finance team, continued to ensure a strong balance sheet and disciplined investment strategy, and provided exceptional leadership in a number of areas integral to our transition to a fully integrated biotechnology company, including strategic planning, investor relations, and financing transactions. We wish him the best in his future.”

ABOUT IMMUNOGEN

ImmunoGen is developing the next generation of antibody-drug conjugates (ADCs) to improve outcomes for cancer patients. By generating targeted therapies with enhanced anti-tumor activity and favorable tolerability profiles, we aim to disrupt the progression of cancer and offer our patients more good days. We call this our commitment to “target a better now.” Our lead product candidate, mirvetuximab soravtansine, is in Phase 3 study for folate receptor alpha (FRα)-positive platinum resistant ovarian cancer, and in Phase 1b/2 testing in combination regimens. Our novel IGN candidates for hematologic malignancies, IMGN779 and IMGN632, are in Phase 1 studies.

Learn more about who we are, what we do, and how we do it at www.immunogen.com.

This press release includes forward-looking statements, including those on Mr. Johnston’s remaining employed through year-end and then serving as a consultant, Mr. Foster continuing in his role, ImmunoGen’s ability to transition to a fully integrated biotechnology company, and the regulatory and commercial potential of our product candidates. Important factors could cause ImmunoGen’s actual results to differ materially from those discussed or implied in the forward-looking statements, and you are cautioned not to place undue reliance on these forward-looking statements, which are current only as of the date of this release. It should be noted that there are risks and uncertainties related to the retention of employees and consultants, the development of novel anticancer products, including risks related to preclinical and clinical studies, their timings and results, the potential that earlier clinical studies may not be predictive of future results, and building a commercial organization. A review of these risks can be found under “Risk Factors” in ImmunoGen’s Annual Report on Form 10-K for the year ended December 31, 2017 and other reports filed with the Securities and Exchange Commission.

INVESTOR RELATIONS CONTACT

THRUST Strategic Communications

Chelcie Lister

910-777-3049

chelcie@thrustsc.com

MEDIA CONTACT

Courtney O’Konek

781-895-0600

courtney.okonek@immunogen.com

OR

FTI Consulting

Robert Stanislaro

212-850-5657

robert.stanislaro@fticonsulting.com