CD8A and neoplasm: In preclinical studies, rhIL-15 has demonstrated superiority over IL-2 in reducing tumor burden and prolonging survival in tumor-bearing mice.195 In patients with renal cell carcinoma and melanoma, rhIL-15 injection induced a significant increase in circulating NK and CD8+ T cells with moderate toxicity.196 However, challenges persist in achieving sustained IL-15 exposure due to its short serum half-life, which restricts its immunostimulatory potency.