Many studies demonstrate the efficacy of closure of a patent ductus arteriosus with indomethacin, but also show that success diminishes markedly with increasing postnatal age. For this reason surgical ligation is usually preferred after the first month of life. We describe the case of a male premature infant (25 weeks gestation, birth weight 680 g), in whom a PDA was successfully closed with indomethacin (0.1 mg/kg once daily intravenously for 6 days) at the age of 11 weeks. Thus it may be concluded that closure by drug may be attempted before surgical ligation even in cases of advanced postnatal age.