Johnson & Johnson (J&J) has agreed to purchase Firefly Bio for $1bn in cash, aiming to strengthen its oncology pipeline with Firefly Bio’s proprietary Firelink degrader-antibody conjugate (DAC) platform.

The deal centres on enhancing targeted treatments for solid tumours driven by KRAS mutations, which are considered especially challenging to treat.

The companies stated that the Firelink DAC technology could enable more precise delivery of protein degraders to tumour cells, minimising impact on healthy cells.

Firefly Bio’s platform is in the preclinical stage and is designed to address limitations of current therapies for Kirsten rat sarcoma viral oncogene homologue (KRAS)-driven cancers.

J&J innovative medicine research and development division executive vice-president John Reed said: “KRAS has notoriously been considered an undruggable target and patients with KRAS-driven cancers continue to face limited treatment options with survival measured in months, not years.

“We believe the proprietary Firelink platform will overcome the limitations of current treatments and diversify our pipeline with preclinical candidates for treating multiple types of solid tumours.”

The transaction is expected to close later this year, subject to regulatory approvals and other customary closing conditions.

Firefly Bio is focused on advancing its Firelink DAC platform in cancer indications where treatment options remain limited.

J&J said it has pursued oncology innovation for more than 30 years and that Firefly Bio’s technology will complement its existing antibody-engineering capabilities.

The announcement did not include details on regulatory submission timelines or potential launch dates.

In March 2026, the US Food and Drug Administration (FDA) approved J&J’s Icotyde (icotrokinra) for the treatment of plaque psoriasis, marking the first US entry of an oral peptide in the indication.