Genentech inc., of south san francisco, said data reported at the north america cystic fibrosis conference in denver showed that pulmozyme (dornase alfa, recombinant) slowed the rate of lung function declines in cf patients. The evaluation was conducted through a review of patient data from a phase iv observational study, the epidemiologic study of cystic fibrosis. The rate of decline in lung function was evaluated in 1,991 patients who had not received pulmozyme for two years, received pulmozyme and remained on it for 80 percent of the time for the following two years, compared to 3,108 cystic fibrosis patients who never received the drug. The mean rate of decline for pulmozyme patients was reduced by 46 percent (p<0.001) during the two years of drug use, with no change in the comparator group. In addition to demonstrating the slower rate of lung function decline in those who received pulmozyme, they also had an immediate improvement in lung function compared to those not treated with the drug.