Preclinical research reported that fucoidan, a seaweed‑derived sulfated polysaccharide, potentiates CAR‑T cell efficacy against non‑Hodgkin lymphoma by modulating the tumor microenvironment and T‑cell function. The study measured improved CAR‑T proliferation, persistence, and tumor clearance in animal models. Authors detailed mechanisms including enhanced immune infiltration, reduced suppressive myeloid signals, and metabolic support for T cells. Fucoidan’s oral availability and low toxicity profile make it an attractive adjuvant to explore in clinical combination trials. Next steps will require dose‑finding, GMP sourcing, and safety studies in humans; if translatable, fucoidan could become a low‑cost adjunct to improve outcomes and durability of CAR‑T therapies.