AbbVie Inc. (NYSE: ABBV) and ImmunoGen, Inc. (NASDAQ: IMGN) today announced a definitive agreement under which AbbVie will acquire ImmunoGen, and its flagship cancer therapy ELAHERE^® (mirvetuximab soravtansine-gynx), a first-in-class antibody-drug conjugate (ADC) approved for platinum-resistant ovarian cancer (PROC). The acquisition accelerates AbbVie's commercial and clinical presence in the solid tumor space. Additionally, ImmunoGen's follow-on pipeline of promising next-generation ADCs further complements AbbVie's ADC platform and existing programs.

Under the terms of the transaction, AbbVie will acquire all outstanding shares of ImmunoGen for $31.26 per share in cash. The transaction values ImmunoGen at a total equity value of approximately $10.1 billion. The boards of directors of both companies have approved the transaction. This transaction is expected to close in the middle of 2024, subject to ImmunoGen shareholder approval, regulatory approvals, and other customary closing conditions.

"The acquisition of ImmunoGen demonstrates our commitment to deliver on our long-term growth strategy and enables AbbVie to further diversify our oncology pipeline across solid tumors and hematologic malignancies," said Richard A. Gonzalez, chairman and chief executive officer, AbbVie. "Together, AbbVie and ImmunoGen have the potential to transform the standard of care for people living with cancer."

ImmunoGen's oncology portfolio has the potential to help drive long-term revenue growth for AbbVie's oncology franchise. Ovarian cancer is the leading cause of death from gynecological cancers in the U.S. ELAHERE is the first targeted medicine to show meaningful survival benefit in PROC. As a fast-growing solid tumor therapy, ELAHERE provides AbbVie with a potential multi-billion-dollar on-market medicine with expansion opportunities in earlier lines of therapy and larger segments of the ovarian cancer market.

"With global commercial infrastructure and deep clinical and regulatory expertise, AbbVie is the right company to accelerate geographic and label expansion, and realize the full potential of ELAHERE as the first and only ADC approved in ovarian cancer," said Mark Enyedy, president and chief executive officer, ImmunoGen. "The addition of ImmunoGen's pipeline, platform, and expertise to AbbVie's oncology portfolio is an exciting opportunity for the combined companies to advance innovation in ADCs. This transaction is the culmination of our 40-year commitment to develop and deliver the next-generation of ADCs and more good days for people living with cancer."

ELAHERE is a first-in-class ADC targeting folate receptor alpha (FRα) with a maytansinoid payload DM4, a potent tubulin inhibitor designed to kill the targeted cancer cells. ELAHERE received U.S. Food and Drug Administration (FDA) accelerated approval in 2022 for the treatment of adult patients with FRα positive, platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal cancer, who have received one to three prior systemic treatment regimens. The positive Phase 3 results from the MIRASOL confirmatory trial will support a Marketing Authorization Application (MAA) to the European Union and a supplemental Biologic License Application (sBLA) submission to the U.S. FDA in order to gain full approval. Ongoing clinical development programs are underway to expand into earlier lines of therapy and enter other large patient segments of the ovarian market over the next 5-10 years.

ImmunoGen's follow-on pipeline of promising next-generation ADCs expands AbbVie's growing oncology pipeline of potentially transformative programs across multiple different solid tumors and hematologic malignancies. ImmunoGen's Phase 1 asset, IMGN-151, is a next-generation anti-FRα ADC for ovarian cancer with the potential for expansion into other solid tumor indications. Pivekimab sunirine, currently in Phase 2, is an anti-CD123 ADC targeting blastic plasmacytoid dendritic cell neoplasm (BPDCN), a rare blood cancer, which was granted FDA breakthrough therapy designation for the treatment of relapsed/refractory BPDCN.

Transaction Terms

AbbVie will acquire all outstanding ImmunoGen common stock for $31.26 per share in cash. The proposed transaction is subject to customary closing conditions, including receipt of regulatory approvals and approval by ImmunoGen stockholders. The proposed transaction is expected to be accretive to diluted earnings per share (EPS) beginning in 2027.

Conference Call Details

AbbVie will host an investor conference call today at 8:00 a.m. CT to discuss this transaction. The call will be webcast through AbbVie's Investor Relations website at investors.abbvie.com. An archived edition of the call will be available after 9:00 a.m. CT. Presentation materials for the investor conference call are available here.

Advisors

AbbVie's lead financial advisor is J.P. Morgan Securities LLC, which has delivered a fairness opinion for the transaction and Wachtell, Lipton, Rosen & Katz is serving as legal advisor. Morgan Stanley & Co. LLC is also serving as a financial advisor to AbbVie.

ImmunoGen's financial advisors are Goldman Sachs & Co. LLC and Lazard, and Ropes & Gray LLP is serving as legal advisor.