M&A analysis: bolt-ons for J&J and Bristol

Optimism is returning to biotech, but there still weren’t any oncology mega-deals in the fourth quarter of 2025. The biggest purchase was Johnson & Johnson’s $3bn swoop for the prostate cancer therapy developer Halda Therapeutics, according to an analysis of OncologyPipeline.

The second-largest deal wasn’t even, strictly speaking, in oncology – at least not yet. Bristol Myers Squibb spent $1.5bn on the in vivo Car-T player Orbital, which has a focus on autoimmune disease; however, the target did appear at least to have ambitions in cancer before the buyout.

As seen in other recent quarters, there were also a few opportunistic buys, including Day One’s cut-price takeover of Mersana. More interesting was Ipsen’s €350m acquisition of ImCheck Therapeutics, which gave it a BNT3A-targeting MAb designed to activate gammadelta T-cells.

A peripheral fourth-quarter purchase saw Halozyme buy a fellow drug-delivery player, Elektrofi, for $750m up front.

The fourth-quarter deals fall well short of the biggest oncology acquisitions of 2025 overall, which saw Sanofi spend $9bn on Blueprint, and Genmab shell out $8bn for Merus.

Still, there’s renewed enthusiasm around M&A, with Revolution Medicines rumoured to be attracting bids of up to $30bn – although the JP Morgan healthcare conference came and went with no deal emerging.

The only notable oncology purchase in 2026 so far is Amgen’s move for Dark Blue Therapeutics for an undisclosed up-front fee.

Halda and in vivo Car-T

Halda attracted J&J’s interest despite the early nature of its lead project, HLD-0915, an androgen receptor-targeting RIPTAC. The move came not long after Halda reported a 59% rate of PSA50 responses among 22 patients with relapsed, metastatic, castration-resistant prostate cancer in a phase 1/2 trial at the Triple meeting.

One question is how Halda will fit into J&J’s prostate cancer pipeline, which includes the anti-PSMA ADC ARX517 – itself the result of the $2bn acquisition of Ambrx in 2024 – and the in-house anti-KLK2 T-cell engager pasritamig.

Meanwhile, in vivo Car-T saw various deals last year, including Gilead’s $350m swoop for Interius, AstraZeneca’s $425m purchase of EsoBiotec and AbbVie’s $2bn move for Capstan (although the last, like Orbital, was mainly focused on autoimmune disease).

Another relatively large deal towards the end of last year saw Halozyme spreading its bets in drug delivery. The company has grown its market cap to over $8bn by licensing its Enhanze hyaluronidase technology to various big pharmas to facilitate subcutaneous drug development.

Now it will also have Elektrofi’s so-called Hypercon microparticle platform, designed to allow ultra-high concentrations of biologicals, thereby reducing injection volume. The private group already had collaborations with the likes of J&J and Lilly, and two partner programmes are set to hit the clinic this year.

Notable oncology M&A in Q4 2025

Notes: excludes SPACs & reverse mergers; *Hanmi previously owned ~20% of Aptose. Source: OncologyPipeline.