VivoSim Labs is a small, early-stage pharmaceutical services company that sells drug toxicity testing services to pharma and biotech companies using 3D bioprinted human tissue models. Its core platform, branded NAMkind, replicates the architecture of human liver and intestinal tissue to predict whether drug candidates will cause organ toxicity — a common cause of clinical trial failures and post-market withdrawals. VivoSim sells these testing services directly to pharma and biotech R&D teams, who outsource safety screening of drug candidates to VivoSim rather than relying on animal models or simpler cell cultures. VivoSim claims its liver toxicity platform achieves 87.5% sensitivity and 100% specificity. The company also plans to offer bespoke investigational services, including mechanism-of-action studies, for higher-value engagements beyond routine screening. VivoSim traces its roots to Organovo Holdings, which originally pursued transplantable tissue printing before pivoting to drug testing services. In March 2025, VivoSim sold its clinical-stage IBD drug program, FXR314, to Eli Lilly for $10M upfront and up to $50M in contingent milestones, fully exiting drug development and rebranding as VivoSim Labs. The company operates with just 13 employees and is in early commercial stage, sustained in part by proceeds from the Eli Lilly transaction.