J&J glows with $1B buyout of Firefly and its degrader platform tech
J&J glows with $1B buyout of Firefly and its degrader platform tech.
Firefly Bio
Private
Firefly Bio is a clinical-stage bioconjugate and antibody-drug conjugate (ADC) company leveraging chemistry pioneered by Nobel laureate Carolyn Bertozzi to develop next-generation ADCs targeting KRAS-mutant and other solid tumors. Its lead programs combine site-specific bioconjugation with tumor-selective payload chemistries designed to widen the therapeutic index versus first-generation ADC platforms.
Company Info
Sector:Biotechnology / Antibody-Drug Conjugates (Oncology)
Headquarters:Watertown, Massachusetts, USA
Founded:2015
Website:fireflybiologics.com/
Funding Round:Acquired by Johnson & Johnson (June 2026)
Total Funding:Acquired for up to $1B by J&J; prior private funding undisclosed
Funding & Investor Relations
IPO Outlook / Plans
Was on a path toward a potential standalone public listing prior to the J&J acquisition announcement in June 2026.
Upcoming Milestones & Key Dates
H2 2026
Corporate
Expected close of Johnson & Johnson acquisition (subject to regulatory approvals)
Late 2026 / 2027
Regulatory
FF-101 IND filing post-J&J integration
Clinical Development Pipeline
FF-101
Target: Anti-KRAS G12D antibody with site-specific topoisomerase 1 payloadFF-201
Target: Anti-KRAS G12C antibody with MMAE payload (Bertozzi chemistry)Undisclosed ADC programs
Target: Site-specific bioconjugate platform; targets undisclosedRecent News
Leadership Team
Careers & Job Openings