4D pharma plc (LBPSW) develops live biotherapeutics, a novel class of biologics derived from the human microbiome, leveraging its proprietary MicroRx platform to identify and refine bacterial strains for therapeutic applications in gastrointestinal disorders; immuno-oncology; respiratory diseases such as asthma; central nervous system disorders including neurodegeneration, multiple sclerosis, and Parkinson's; and autoimmune conditions like rheumatoid arthritis. Core products in its pipeline include MRx0518, an immuno-oncology candidate evaluated in combination with Merck's Keytruda for solid tumors; Blautix for irritable bowel syndrome; Thetanix for pediatric Crohn's disease; MRx-4DP0004 for asthma; MRx0029 and MRx0005 for CNS disorders; MRx1299 for solid tumors; MRx0006 for rheumatoid arthritis; and MRx0002 for multiple sclerosis. The company targets patients with unmet needs in these areas through single-strain live biotherapeutic products (LBPs) administered orally or otherwise, supported by its MicroDx microbiome profiling for diagnosis and treatment; it previously operated GMP-certified manufacturing in León, Spain, and research facilities in Aberdeen, Scotland; Cardiff, Wales; Italy; Ireland; and the United States. Founded in 2014 and formerly headquartered in Leeds, United Kingdom, with the parent entity incorporated on 10 January 2014 as Schosween 18 Limited, 4D pharma conducted global clinical trials across North America and Europe while maintaining AIM and Nasdaq listings following a 2021 merger with Longevity Acquisition Corporation that raised approximately $40 million. In recent major developments, the company entered administration in June 2022 amid creditor funding challenges, resulting in suspension and cancellation of its AIM trading in February 2023, Nasdaq delisting in 2022, and formal dissolution on 24 September 2025, with ongoing creditor processes including notices of intended dividends as of April 2025.