UGT1A1 and Hyperbilirubinemia: In a subpopulation of patients who were genotyped for UGT1A1 polymorphisms in the phase III COMPARZ study, UGT1A1*28, *37 or *6 homozygotes or inferred compound heterozygotes had higher baseline bilirubin and were more likely to experience hyperbilirubinemia (OR 9.97, 95% CI 4.13–24.03, p = 7.7 × 10−8) [32].