10 Multibillion-Dollar M&As That Closed Since July 2023


Pictured: Handshake in front of raining money / Taylor Tieden for BioSpace

The slow pace of mergers and acquisitions in 2022 continued into 2023 but has since picked up steam, highlighted by a frenzy of big-dollar M&A announcements and the closing of Pfizer’s $43 billion purchase of Seagen, the largest pharmaceutical or biotech M&A agreement in three years. 

As M&A activity accelerates in early 2024, BioSpace looks back over the biggest deals in the biopharma sector over the past eight months. This list includes M&A transactions that have closed since July 1. 

1. Pfizer Snatches Up Seagen to Expand Oncology Pipeline

Closing date: Dec. 14, 2023

Deal value: $43 billion

Pfizer acquired Seattle-based Seagen for $43 billion, the largest M&A agreement in the sector in three years and just missing the list of top 10 biopharma deals of all time. With this move, Pfizer took control of Seagen’s antibody-drug conjugate (ADC) technology, fortifying the pharma giant’s standing within the oncology market. Pfizer’s offering came in at $229 per share, outbidding others, including Merck and Sanofi.

The deal took nine months to consummate after scrutiny by the Federal Trade Commission as well as European regulators. In response to FTC concerns, Pfizer decided to donate the rights of royalties from U.S. sales of its anti-PD-L1 checkpoint inhibitor Bavencio to the American Association for Cancer Research.

2. AbbVie Acquires ADC Developer Immunogen

Closing date: Feb. 12, 2024

Deal value: $10.1 billion

The antibody-drug conjugate (ADC) market is hot, and AbbVie is now in the race after acquiring ImmuoGen for $31.26 per share.

The deal offers AbbVie access to ImmunoGen’s ADC Elahere (mirvetuximab soravtansine-gynx), which was granted FDA accelerated approval in 2022, as well as the smaller company’s follow-on pipeline of ADCs, including several in development for treatments such as solid tumors, acute myeloid leukemia and blastic plasmacytoid dendritic cell neoplasm.

3. Biogen Boosts Neuro, Rare Disease Pipelines with Reata Acquisition

Closing date: Sept. 26, 2023

Deal value: $7.3 billion

Biogen scooped up Reata Pharmaceuticals to bolster its neurological and rare disease businesses. Biogen paid $172.50 per share to score the Texas-based firm.

Last year, Reata gained FDA approval for Skyclarys (omaveloxolone), the first authorized treatment for Friedreich’s ataxia in the U.S., and new owner Biogen followed with European Commission approval this month. The purchase also gave Biogen access to Reata’s developmental pipeline, which includes the Hsp90 modulator cemdomespib, being developed for diabetic peripheral neuropathic pain, and the Nrf2 activators RTA 415 and RTA 417, both being assessed for their potential in treating diseases associated with mitochondrial dysfunction, oxidative stress and chronic inflammation.

4. Roche Buys Telavant from Roivant to Acquire IBD Candidate

Closing date: Oct. 23, 2023

Deal value: $7.1 billion

Roche made an upfront payment of $7.1 billion to secure Telavant Holdings, a company that Roivant Sciences previously owned 75% of. The acquisition agreement also includes an additional short-term milestone payment of $150 million.

Telavant has the rights in the U.S. and Japan to investigational anti-TL1A antibody RVT-3101, which is being developed for inflammatory bowel conditions, including ulcerative colitis and Crohn’s disease. RVT-3101 is a monoclonal antibody that works by inhibiting the TL1A cytokine, which modulates the site and severity of inflammation and fibrosis by stimulating the TH1 and TH17 pathways.

5. Astellas Nabs Iveric Bio and Its Blindness Therapies

Closing date: July 11, 2023

Deal value: $5.9 billion

Astellas Pharma acquired New Jersey–based Iveric Bio for $5.9 billion in its largest acquisition to date. Under the terms of the agreement, Astellas paid $40 per share.

The acquisition grants Astellas access to multiple programs for the treatment of geographic atrophy due to age-related macular degeneration, including Izervay, a complement C5 inhibitor that received FDA approval in August.

6. Danaher Scoops Up Abcam After Shareholder Pushback

Closing date: Dec. 6, 2023

Deal value: $5.7 billion

Danaher paid $5.7 billion to acquire Abcam, a U.K.-based supplier of antibodies, reagents and other proteomic research tools. The transaction was valued at $24 per share, a price initially deemed too low by Abcam founder-turned-investor Jonathan Milner, who tried to have himself installed as executive chairman last year.

7. BMS Acquires Mirati Therapeutics to Boost Cancer Business

Closing date: Jan. 23, 2024

Deal value: $4.8 billion

Bristol Myers Squibb took over cancer-focused biotech Mirati Therapeutics in a bid to grow its oncology franchise, at a cost of $58.00 per share. Additionally, Mirati shareholders received nontradeable value rights worth up to $12.00 per share, contingent on the FDA accepting the New Drug Application for Mirati’s candidate MRTX1719 within seven years of the acquisition. That puts the potential total value as high as $5.8 billion.

MRTX1719 is a potentially first-in-class PRMT5 inhibitor in early-stage development for several tumor types, including non-small cell lung cancer. The compound is expected to enter Phase II studies in the first half of 2024.

8. Novartis Expands in the Renal Space, Acquiring Chinook Therapeutics

Closing date: Aug. 11, 2023

Deal value: $3.2 billion

Novartis acquired Seattle-based Chinook Therapeutics, a prominent player in kidney therapeutics, in a deal valued at up to $3.5 billion, or $40 per share. Specifically, Novartis provided an initial cash payment of $3.2 billion and has committed to additional contingent value rights of up to $300 million.

Novartis gained access to Chinook's two advanced-stage assets currently under late-stage clinical development for immunoglobulin A nephropathy (IgAN), a rare, progressive autoimmune kidney disease.

9. Roche Acquires Carmot Therapeutics to Enter Weight-Loss Drug Arena

Closing date: Jan. 29, 2024

Deal value: $2.7 billion

Roche took over Berkeley, California–based Carmot Therapeutics, a move that could place it in the thick of the lucrative and increasingly competitive weight-loss market. The Swiss pharma made an upfront payment of $2.7 billion when the deal closed last month, and privately held Carmot’s investors equity holders are eligible for up to $400 million in additional milestone payments.

With the purchase, Roche gains access to Carmot’s portfolio of preclinical and clinical assets, including three GLP-1 receptor agonists aimed at treating obesity. Carmot’s lead asset is CT-388, a dual agonist of both the GLP-1 and GIP receptors that is ready for Phase II testing.

10. Lilly Obtains DICE Therapeutics and Its Drug Discovery Platform

Closing date: Aug. 9, 2023

Deal value: $2.4 billion

To expand its range of treatments for autoimmune diseases, Eli Lilly acquired DICE Therapeutics, a biopharma company based in San Francisco. Lilly reported that the deal is valued at $48 per share.

The purchase grants Lilly the opportunity to use DELSCAPE, DICE’s drug discovery and development platform. This platform is designed to optimize the creation of small molecule drugs, allowing for efficient disruption of protein-protein interactions.

Deals to Watch

Neil Versel is the business editor at BioSpace. You can reach him at neil.versel@biospace.com. Follow him on LinkedIn or X.