High-affinity binding of HLA-DRB1 alleles was associated with asparaginase hypersensitivity reactions. (A) Patients with high-affinity binding alleles had a higher incidence of asparaginase hypersensitivity compared with patients with low-affinity binding alleles (n = 1870, P = 3.3 × 10⁻⁴). (B) Estimated ORs for association of HLA-DRB1*01:01, HLA-DRB1*04:02, HLA-DRB1*04:05, HLA-DRB1*04:08, HLA-DRB1*07:01, HLA-DRB1*14:01, and HLA-DRB1*15:01 alleles with asparaginase hypersensitivity, all at P < .1, are shown vs the predicted binding category (predicted low-binding alleles are shown in blue; predicted high-binding alleles are shown in red). All HLA-DRB1 alleles had predicted binding affinities consistent with the estimated odds ratios.