DIRECT COMPARISON OF SN-MESOPORPHYRIN, AN INHIBITOR OF BILIRUBIN PRODUCTION, AND PHOTOTHERAPY IN CONTROLLING HYPERBILIRUBINEMIA IN TERM ANDNEAR-TERM NEWBORNS

Background. Sn-mesoporphyrin (SnMP) is a potent inhibitor of bilirubin production. In our previous studies a single dose (6 mu mol/kg birth weight) significantly moderated hyperbilirubinemia and reduced phototh erapy (PT) time by > 75% when administered within 24 hours of birth to preterm infants. Objective. To directly compare the efficacy of SnMP and PT for controlling hyperbilirubinemia in term and near-term infant s. Methods. Two randomized, sequentially analyzed trials (Study I: mal e term infants; Study II: infants of both sexes and gestational age [G A] 245-265 days) were conducted. SnMP (6 mu mol/kg birth weight) or PT (Phillips F20T12/BB lamps) was administered to paired infants accordi ng to strict criteria of plasma bilirubin levels and age. Time of enro llment and closure of cases and crossover, if necessary, of SnMP infan ts to PT or all infants to exchange transfusion were precisely defined in each pair. SnMP or PT was considered superior if the time between enrollment and closure of the case was reduced by > 24 hours over the alternative treatment or if crossover had occurred. Results. None of t he 44 SnMP-treated infants required supplemental PT. Of the 22 pairs o f term infants enrolled in Study I, SnMP proved superior to PT in 20 a nd equal in two. Of the 20 pairs of near-term infants enrolled in Stud y II, SnMP was superior in 12 and PT in two; six were tied. Two SnMP-t reated infants were unpaired. The PT-treated infants in Study I requir ed an average of 33 hours of treatment; those in Study II, 48 hours. N one of the enrolled infants required exchange transfusion or interrupt ion of breast-feeding. In both studies, times between case enrollment and closure were reduced by > 30 hours in SnMP compared with PT infant s; requirements for additional days of medical observation and bilirub in measurements were also significantly less in SnMP infants. Conclusi on. A single dose of SnMP entirely supplanted the need for PT in jaund iced term and near-term newborns and significantly reduced medical res ource use to monitor hyperbilirubinemia.