Top biotech deals in November 2025 

As 2025 draws to a close, the typical end-of-the-year slowdown was not a thing for the biopharma industry, and certainly not in the An end-of-the-year slowdown has not been a thing for the biopharma industry yet, and certainly not in the biotech deals space in November.dealmaking and fundraising spaces. Antibodies were popular last month, and so were the fields of cell therapies and artificial intelligence (AI). Several licensing deals were announced, with Lilly topping the charts, having signed five major deals in November. 

Top biotech M&A deals of November 2025 

Big pharmas swallowing up biotechs is part and parcel of the biopharma industry, and many of them bet big on new technology that they think could make it to the public. Although the month of November saw a drop in the number of mergers and acquisitions (M&As) in the space compared to the whopping $17.8 billion deals across nine major M&As in October, sizeable buyouts suggest that the industry is still going strong as we approach the end of the year. 

Merck’s acquisition of California- based immunotherapeutics company Cidara Therapeutics was a notable one last month. The American pharma giant is spending $9.2 billion on the latter’s pipeline of drug-Fc conjugate (DFC) therapies. Small molecules and peptides are bound to an antibody fragment to make these therapies. Merck will soon get a hold of Cidara’s lead candidate in phase 3 studies, CD388, a small molecule neuraminidase inhibitor connected to an Fc fragment of a human antibody designed to prevent influenza A and B. The candidate was designated fast track status by the U.S. Food and Drug Administration (FDA). 

Another multibillion-dollar acquisition was Johnson & Johnson’s purchase of Connecticut-based Halda Therapeutics. The big pharma paid $3.05 billion for the Yale University-spinout, which is the developer of the first-ever regulated induced proximity targeted chimera (RIPTAC) to hit the clinic in March. Similar to protein degraders, this up-and-coming class of drugs is designed to kill cancer cells by bringing together two proteins. The lead RIPTAC is being tested for prostate cancer. 

Meanwhile, another pharma giant Pfizer is merging with the obesity therapeutics company Metsera for $86.25 per share, around $10 billion. The New York-based startup has chased the high-grossing GLP-1 agonist market since 2022 and has a candidate in phase 2 trials at the moment.  

The merger was the result of a contentious bidding war with Novo Nordisk. Although Pfizer was initially poised to acquire Metsera for $4.9 billion, the Danish drug giant Novo swooped in to outbid Pfizer offering the latter $6.5 billion upfront in September. Pfizer took Novo to court, playing the competition law violation card, as Novo Nordisk dominates the obesity market with its medicines Ozempic and Wegovy reaping billions and billions of dollars. Pfizer came out strong in the end, marking its first buyout this year.  

Besides, California-based Day One Biopharmaceuticals is snapping up Massachusetts-based Mersana Therapeutics, which develops antibody-drug conjugates (ADCs) for $285 million. The deal will see Mersana’s ADCs for solid tumors accompany Day One’s own pipeline of medicines aimed at broadening cancer care. 

Biotech deals by approach in November 2025 

Antibodies drive biopharma industry 

Like always, antibodies were a hit among dealmakers. Pharma giant Lilly forged two deals in the field last month. One was a $2.602 billion pact with South Korean ABL Bio. The Seoul-based startup will use the money to create bispecific antibodies from its technology platform Grabody-B. It has previously collaborated with French giant Sanofi in Parkinson’s research and Maryland-headquartered cancer therapeutics company I-mab Biopharma to treat solid tumors. As part of the Lilly deal, ABL will secure $40 million upfront. 

Lilly’s second deal in the field was with Chinese biotech Ailux for its antibody discovery platform that uses artificial intelligence (AI). With Ailux poised to receive $345 million, the two will work on bringing antibodies to the clinic to treat various undisclosed conditions. Lilly was on a shopping spree last month, having announced five licensing agreements. 

Meanwhile, South Korean monoclonal antibody developer Celltrion is banding together with Kaigene, a Maryland-based developer of antibodies and fusion proteins. Kaigene will score $8 million upfront and up to $736 million in potential milestone payments. This includes $11 million in near-term milestones, which Kaigene can claim once the phase 1 studies of its antibodies targeting autoimmunity, KG006 and KG002, have begun.  

Further, GSK was back again with its $50 million deal with California-based LTZ Therapeutics last month, following its splurge on the RNA space in October. LTZ, which already has a pipeline of T-cell engagers to treat cancer – two of which are in the investigational new drug (IND)-enabling stage – will soon be designing up to four more engagers to address blood cancers and solid tumors. Once in preclinical trials, GSK can choose to develop them further and license their potential commercialization worldwide.  

To add to that, in Pfizer’s second agreement in November, it united with Massachusetts-based Nona Biosciences to discover new antibodies with the help of its Harbour Mice platform. The financial terms of the deal were not disclosed. Nona is no stranger to collaborations, having worked with California-based Candid Therapeutics and British big pharma AstraZeneca in the past.  

Cell therapies join ranks of antibodies in deal-making arena 

In the popular technological field of cell therapies, Pennsylvania-based Third Arc Bio is joining forces with Chinese drug developer Adagene to develop T cell engagers. These are often bispecific antibodies that bring immune cells of a patient close to cancer cells to trigger an attack and kill them. Adagene’s SAFEbody technology, which allows the activation of an antibody when it comes in contact with a tumor, will be used to design these engager therapies. As part of the agreement, it will make $5 million upfront and will be eligible to receive up to $840 million in development and commercial-based milestones. The Chinese biotech has forged relations with California-based cancer therapeutics company Exelixis and Sanofi this year in the antibodies space. 

In addition, Singapore’s ImmunoScape has clinched a deal with Massachusetts-based biologics developer Cue Biopharma to make headway on the in vivo cell therapies front. This process involves engineering a patient’s own cells inside their own body by delivering genes or other genetic material to target cells. Cue will reel in $15 million upfront, $10 million by the end of this year, an additional $5 million a year later, and 40% equity stake in the Singaporean biopharma. 

Besides, it looks like Boehringer Ingelheim is dipping its toes in different research and development (R&D) fields after it inked pacts in the gene therapies and ADCs space two months ago. It is now collaborating with Swiss antibody developer CDR-Life to treat autoimmunity with the latter’s antibody-based T cell engager, CDR111. The candidate is designed to target and deplete B cells, with the goal of reseting the immune system, specifically in conditions such as lupus, multiple sclerosis and certain forms of arthritis. As the German giant will gain the rights to potentially commercialize CDR111, CDR-Life is entitled to up to CHF 456 million ($570 million) in total payments. 

Can AI help discover drugs? Biopharma investors think so 

Unlike the U.S.-based Merck, the German giant Merck was not up to any M&As last month, and it last bought cancer care company SpringWorks Therapeutics in April. However, it did close a deal with Valo Health, a Massachusetts-based drug discovery company that uses AI to uncover potential medicines, for more than $3 billion in upfront and milestone payments. Valo has chummed up to big pharmas in recent times, with its collaboration with Novo Nordisk in heart health research as well as Pfizer. 

Then there’s Swiss giant Roche, which has tapped Massachusetts-based Manifold Bio to develop brain shuttles for central nervous system (CNS) diseases. These are basically carriers of that transport medicines to the brain via the blood-brain-barrier, which is normally not easy for large molecules to cross. For $2 billion in milestone payments and $55 million upfront, Manifold will identify these shuttles for neurodegenerative diseases, a technological field that Roche has had experience in for more than 15 years. 

Moreover, Lilly struck yet another deal in November with Massachusetts-based Insilico Medicine, which uses a generative AI software to help discover potential new drugs. Insilico is eligible to receive over $100 million in upfront and milestone payments, and tiered royalties on sales if any of the medicines born out of the collaboration are commercialized. The two have teamed up before, and for Lilly, it’s not its first rodeo in the AI drug discovery field. It sealed a deal with multi-trillion-dollar chipmaker Nvidia to build a supercomputer to help identify new medicines two months ago. 

Lilly stocks up on gene therapies  

In Lilly’s final haul, it signed two deals to expand its presence in the gene therapies sector. The first was with New York-headquartered MeiraGTx to gain worldwide exclusive rights to the latter’s AAV-AIPL1 program to treat Leber congenital amaurosis 4, a severe eye disorder. MeiraGTx will snap up $75 million upfront and can reap more than $400 million in total milestone payments.  

The second gene therapy pact was with Massachusetts-based clinical-stage startup SanegeneBio, which is centered on RNA interference (RNAi) research. The point of RNAi is to silence certain genes and tone down gene expression linked to diseases, and in the case of the SanegeneBio deal, the focus is on metabolic diseases. SanegeneBio can rake in up to $1.2 billion in milestone payments and will be paid an undisclosed upfront amount. All this comes after Lilly’s 2025 acquisitions of Verve Therapeutics and Adverum Biotechnologies, both players in gene therapeutics. 

Small molecules are a big deal 

Although small molecules weren’t much sought-after last month compared to other months this past year, American biopharmas Voyager Therapeutics and Transition Bio docked a deal in the sector in November. The Massachusetts-based drug discovery platform company Transition Bio and neuroscience company Voyager have charted the course together in addressing neurodegenerative conditions such as frontotemporal dementia and amyotrophic lateral sclerosis (ALS) – a motor neuron disease. The two will discover and develop novel small molecules that target TDP-43, a protein when dysregulated, leads to neurodegeneration. As part of the agreement, Transition was awarded an undisclosed multi-million-dollar payment upfront and is eligible to receive up to $500 million in milestones. 

Meanwhile, pharma giant Biogen, eyeing Canadian Dayra Therapeutics’ macrocylic peptide design skills, has now tasked it with discovering and developing these drugs to treat immune system-related conditions. Macrocyclic peptides are supposed to be more target-specific than traditional small molecules. The newly launched Toronto-based startup will receive $50 million upfront and is eligible to gain an undisclosed amount in preclinical and clinical development milestones. 

COVID vaccines and platforms attract funding 

Furthermore, California-based Dynavax and Vaxart have partnered to develop a COVID-19 vaccine. The vaccine in question is Vaxart’s phase 2 candidate, which it will continue developing through phase 2, after which, Dynavax will gain worldwide licensing rights to it. Vaxart will secure $25 million upfront as well as a $5 million equity investment from Dynavax, along with additional potential milestone-based payments, depending on whether Dynavax takes its development further. 

Finally, Italian multinational biopharma Chiesi Group has called on AbbVie-owned Aliada Therapeutics to advance a platform technology focused on creating medicines that pass through the blood-brain-barrier to treat lysosomal storage disorders. These are a group of rare genetic diseases where a missing enzyme in cells causes the toxic buildup of certain substances in the body. Aliada’s platform is meant to help develop enzyme replacement therapies for patients with unmet medical needs. The financial terms of the deal were undisclosed.