Top biotech deals in December 2025  

As all eyes are on what will go down at the JPM Healthcare Conference next week, an event known to be a hub for deal-making, let’s look at the licensing deals and mergers and acquisitions (M&As) that took place in the biopharma industry in December 2025. Small molecules and antibodies pulled in major deals, and the month was a busy one with various M&As in the fields of rare, infectious, and metabolic disease therapeutics. 

Top biotech M&As of December 2025  

Despite the holiday season, the biopharma industry did not experience much of a slowdown in December 2025. The most expensive buyout was multinational biotech BioMarin’s $4.8 billion acquisition of New Jersey-headquartered Amicus Therapeutics, a developer of medicines to treat rare diseases. The former being a rare disease therapeutics company itself, it looks like the purchase – BioMarin’s biggest deal ever – is a means for BioMarin to further expand its position in the rare disease space. It will now own Amicus’ small molecule migalastat for Fabry disease, a genetic condition where the body lacks an enzyme leading to the build-up of fats in cells and organs. 

Next in line was Swedish rare disease drug developer Sobi’s acquisition of California-based Arthrosi Therapeutics. The Stockholm-headquartered pharmaceutical plans to spend $1.5 billion to gain control of Arthrosi’s URAT1 inhibitor for a condition called tophaceous gout, which is an advanced stage of gout where crystals of uric acid form lumps around the joints and tendons. Arthrosi’s other clinical candidate for chronic kidney disease will also soon be in Sobi’s hands. This came two months after the American biotech secured $153 million to potentially bring its gout drug to the market. 

Meanwhile, Massachusetts-based Akebia Therapeutics has spent $12 million for fellow Massachusetts-based drug developer Q32 Bio’s complement inhibitor. These are drugs that block the complement system, which is part of the immune system, and they are designed to halt inflammation in the body. The complement inhibitor in question is bempikibart for alopecia areata, an autoimmune condition that causes baldness. The latter can earn up to $592 million in milestone payments. 

As well, California-based Mirum Pharmaceuticals is set to procure fellow California-based Bluejay Therapeutics for $620 million in cash and stock. Bluejay’s pipeline consists of medicines for viral infections, the most advanced one being a phase 3 monoclonal antibody for hepatitis D. As trial results are poised to come out later this year, Mirum hopes to take it beyond the clinic. 

Furthermore, California-based zombie biotech buyer XOMA Royalty set its sights on Massachusetts-based Generation Bio ever since the latter had a major comedown last year, as it shed 90% of its workforce in August. For around $4.29 per share, Xoma will now take over Generation. Plus, the latter’s stockholders will receive one nontransferable contingent value right (CVR) per share. This includes proceeds from a licensing deal with Moderna over its lipid nanoparticle delivery platform in 2023. 

Finally, Cambridge, U.K.-based Cycle Pharmaceuticals is buying New York-based rare disease company Applied Therapeutics for $0.088 per share. As part of the deal, it will scoop up Applied’s aldose reductase inhibitor govorestat for galactosemia, a metabolic disorder that affects the nervous system. Currently stuck in regulatory limbo as its approval was struck down by the U.S. Food and Drug Administration (FDA) in late 2024, Applied has faced various setbacks, culminating in layoffs last year. Cycle is now expected to bring govorestat to the market if cleared by the FDA. 

Biotech deals by approach in December 2025 

Small molecules back in business 

While November didn’t see as many deals in the small molecules space, December was back to the usual frenzy over these medicines. French company Laboratoires Théa has signed off the licensing rights of its candidate ILYX-002 over to California-based Iolyx Therapeutics signed a licensing deal. The phase 3-ready small molecule is being evaluated to treat dry eye disease caused by autoimmunity. Iolyx will nab up to $280 million, including clinical, regulatory, and commercial conditional milestone payments. 

Furthermore, New York-based Formation Bio is uniting with Zhejiang-based Lynk Pharmaceuticals to develop the TYK2 inhibitor LNK01006, which recently got the FDA nod to begin first-in-human studies to address diseases affecting the central nervous system (CNS) like multiple sclerosis later this year. As part of the collaboration, the Chinese biotech will gain a minority equity stake in Formation’s subsidiary Bleecker Bio and up to $605 million in upfront and milestone payments. This comes after Formation raised $372 million in a series D round in 2024.  

Massachusetts-based Zealand Pharma is now allied with Shanghai-based OTR Therapeutics to discover and develop small molecules to treat metabolic diseases. OTR will snap up $20 million upfront, which could go up to $30 million, according to the release. Plus, OTR stands to make up to $2.5 billion in potential preclinical, development, regulatory, and commercial milestone payments. A month before the deal was announced, Zealand revealed that it had paused the development of its GLP-1/2 candidate dapiglutide following lukewarm results in an obesity trial. 

Meanwhile, pharma giant AstraZeneca has inked an agreement with Beijing-based Jacobio Pharma, bagging the exclusive rights to develop and commercialize JAB-23E73 outside of China. The candidate is a KRAS inhibitor that blocks mutated KRAS proteins – once regarded as undruggable targets – in cancers. Jacobio will gain $100 million upfront and is eligible to rake in up to $1.915 billion in milestones. AstraZeneca took a particular shine to biotechs in Asia last year, having spent over $10 billion to build Beijing into a research and development (R&D) hub.  

Another pact in the small molecules space was made between Washington-based Athira Pharma and Ohio-based Sermonix Pharmaceuticals. As the latter’s lasofoxifene gears up for phase 3 studies in breast cancer, it will be handed over to Athira to take it through clinical trials. Athira can reap up to $146 million in milestone payments. Meanwhile, Athira secured $90 million in a private placement. 

Lastly, German giant Boehringer Ingelheim and Massachusetts-based Rectify Pharma are partnering to advance medicines for chronic kidney disease that target the ABCC6 protein. Rectify will receive an undisclosed upfront amount and can earn up to $448 million in preclinical, clinical, regulatory, and commercial milestones. It looks like Boehringer wants a major stake in the kidney disease therapeutics market as it just forged a $120 million deal with Washington-based Variant Bio this week. 

GLP1 agonists: surge in interest continues 

Meanwhile, American giant Pfizer has partnered with Chongqing-based YaoPharma to develop the GLP-1 agonist YP05002, which is currently in phase 1 studies for obesity. YaoPharma will gain $150 million and is eligible to receive up to $1.935 billion in milestone payments. The GLP-1 market has exploded of late, and recently, the FDA approved the first pill – Wegovy – to treat obesity.  

Antibodies grip biopharma industry 

Like in November, antibodies were popular last month. Sanofi has eyed up antibodies for a while now, having doubled down on its bispecific antibodies partnership with Adagene last year. Then, last month, it penned a $1.04 billion deal with South Korean pharma ADEL as well as a $1.7 billion one with California-based Dren Bio. The ADEL pact includes an $80 million payment upfront in exchange for the Seoul-based biotech’s antibody ADEL-Y01, which targets abnormal tau proteins, a hallmark of Alzheimer’s disease. 

The French big pharma’s second agreement last month with Dren is focused on discovering multispecific antibodies. This is following Sanofi’s acquisition of Dren’s DR-0201 – now dubbed SAR448501 – back in May. Dren will gain $100 million upfront and can get up to $1.7 billion in development, regulatory, and commercial milestones.  

Aside from Sanofi, Bristol Myers Squibb (BMS) was another pharma giant wanting in on antibodies last month. It is cooperating with Shanghai-based Harbour BioMed to discover and develop multispecific antibodies. The latter will bag $90 million upfront and up to $1.035 billion in development and commercialization milestones. BMS has previously signed deals over bispecific antibodies like BioNTech’s BNT327 in June. 

Besides, New York-based Yarrow Bioscience and Shanghai-based GenSci are forging a $1.365 billion deal to develop GS-098 to treat two autoimmune conditions, Grave’s disease and thyroid eye disease. The candidate is a monoclonal antibody. Yarrow will hold the rights to develop, manufacture, and commercialize the therapy outside of China. The Chinese biotech will rack up $70 million upfront and $50 million in near-time milestones. 

Sichuan-headquartered Kelun-Biotech and Massachusetts-based Crescent Biopharma have coupled up to develop treatments for cancer. The two plan on developing their respective candidates – possibly as a combination therapy – CR-001, a bispecific antibody, and KB105, an antibody-drug conjugate (ADC), and potentially commercializing them globally. Both therapies are on track to hit phase 1/2 trials soon. Kelun-Biotech will gain $80 million upfront and is eligible to receive up to $1.25 billion in milestones, and Crescent will rein in $20 million upfront and can get up to $30 million in milestone payments.  

Meanwhile, Basel-based Windward Bio’s affiliate LE2025 Therapeutics and Chinese biotech Qyuns Therapeutics have come together to develop and commercialize the bispecific antibody WIN027 designed to target inflammation to treat skin and breathing conditions. As Windward will grab the rights to develop the antibody, Qyuns can snag up to $700 million in milestones. 

Furthermore, California-based Vir Biotechnology has handed over the commercial rights of the combination therapy – currently in phase 2 trials – consisting of the monoclonal antibody tobevibart and the small interfering RNA elebsiran for the treatment of chronic hepatitis delta to market in Europe, Australia, and New Zealand to Norgine Pharma UK. Vir will nab an initial reimbursement payment worth €55 million (64.29 million) when the deal closes and can get up to €495 million ($578.57 million) in clinical, regulatory, and sales milestones. 

Billion-dollar ADC deals in the mix 

Apart from the Kelun-Biotech-Crescent Biopharma collaboration over the ADC KB105, another ADC deal was made between French pharmaceutical Ipsen and Jiangsu-based Simcere Zaiming. Simcere’s preclinical candidate SIM0613 is intended for solid tumors. The Chinese startup is set to achieve up to $1.06 billion in milestone payments. 

Genetic medicines to treat neurological and rare diseases 

London-headquartered pharma giant GSK and Massachusetts-based CAMP4 have joined hands to push the development of antisense oligonucleotides (ASOs) to treat neurodegenerative and kidney diseases. The American biotech’s RAP Platform will be employed to identify RNAs controlling the expression of multiple gene targets and discover ASOs. In return, it will obtain $17.5 million upfront as well as milestone payments. About a year ago, GSK signed a slew of deals in various fields. We’ll have to see if it repeats the move this year. 

Moreover, New York-headquartered Regeneron and Massachusetts-based genetic medicines developer Tessera Therapeutics have inked a deal where both will jointly develop the gene therapy TSRA-196 to treat alpha-1 antitrypsin (AAT) deficiency, an inherited genetic disorder that causes low levels of the AAT protein that protects the lungs and liver. Tessera will secure $150 million, while the costs involved in development and the potential profits will be split between the two. 

Big pharma goes hard on artificial intelligence

In the field of artificial intelligence (AI) in drug discovery, Swiss giant Novartis has collaborated with Relation Therapeutics to find and advance novel targets to address atopic diseases, which are allergic conditions that include eczema, asthma, and hay fever. The London-based startup will receive $55 million and can amass up to $1.7 billion in preclinical, development, regulatory, and commercial sales milestones. 

Next, California-headquartered multinational biopharma Genentech and Texas-based Caris Life Sciences plan to use AI to identify and validate cancer targets to treat solid tumors. Caris will receive $25 million in upfront and near-term payments and is eligible to earn up to $1.1 billion in milestone payments. Last year was a big one for Caris as it went public for $400 million back in June. 

Finally, in Pfizer’s second deal to close the year, it made an $890 million pact with Washington-based Adaptive Biotechnologies to identify T-cell receptors (TCRs) involved in the manifestation of rheumatoid arthritis, which is a kind of autoimmune condition where the immune system mistakenly attacks the body’s joints. The deal will allow the pharma giant to use Adaptive’s antigen-binding dataset to train its own AI and machine learning models for drug discovery.