GRI Bio is a clinical-stage biopharmaceutical company developing oral drug candidates that target Natural Killer T (NKT) cells — immune cells that, when dysregulated, drive inflammation and fibrosis. The company has no approved products, no revenue, and four employees. GRI Bio's lead candidate, GRI-0621, is an oral formulation of tazarotene (already FDA-approved topically for psoriasis and acne) being developed to treat idiopathic pulmonary fibrosis (IPF), a rare and fatal progressive lung scarring disease. GRI Bio argues GRI-0621 targets the upstream immune dysfunction driving fibrosis, unlike existing IPF drugs, which slow lung function decline but haven't improved survival. GRI-0621 completed a Phase 2a trial in 35 IPF patients, meeting primary safety endpoints with no serious adverse events and showing exploratory improvements in lung function. GRI Bio plans to advance GRI-0621 into a Phase 2b trial, either independently or with a partner. The company's second candidate, GRI-0803, targets a different NKT cell subset to treat autoimmune diseases, initially focused on systemic lupus erythematosus; it is in preclinical development with a Phase 1 IND filing planned for 2026. GRI Bio retains worldwide rights to all candidates and may pursue commercialization independently for rare disease indications using a focused sales force, or partner with larger pharmaceutical companies for broader indications or geographies. All activity is contingent on raising additional capital.