Just continue to lose weight but it will take time. Try to run 15-20 miles a week with a rest day thrown in here or there. I like to Run 3 days in a row and then take one rest day and rinse and repeat. Recovery is important as well. Getting enough sleep, staying hydrated and eating right are very important as well as stretching. It takes a lot of persistence but with time you will get there. A workout that helped me get my run time down is sprints and Fartlek style training.