If cystic fibrosis research is anything like cancer, AIDS, or other auto-immune diseases, there may not be a cure for these things in our lifetime, though its still too early to tell. What they are going to come up with are new and improved oral medications that make life easier and longer.
Many of us as parents of a sick child feel cheated, since we've been told when our children were babies that there would be a cure in 10 years, and we raise money every year, we walk for a cure, we gather all our hopes and energies. It was unrealistic anyway, since children cannot be part of experimental drugs and treatments in looking for a cure. Sure, they can be part of government experimentation and surveillance, but they can't be up for testing something that hasn't been approved by the FDA.
I believe they told us that the peak performance for girls in lung function is age 16, and then it just slowly declines after that, years of bouts of illness can cause damage and added mucus that the CF'er can't get rid of. However, my daughter has never grown psudemonas or B cepacia, two bacterias of CF that are thought to lead to a steady decline in lung function. She has a rare genotype and a common genotype and the rare gene keeps her healthy. In fact, my daughter is an amazement to the docs and nurses because she has gone this long with no psuedomonas. God willing, this will continue.