In order for him to take the weight off you need to cut out all treats and cut back on the food. Are you feeding a good quality food now? How much are you feeding and how often. Bogey needed to lose weight too. Last winter he was up to 14.5 lbs
He's a big boy but surely didn't need to weight that much. He's not down to 10.4 lbs. I cut out all treats and cut his food back to less than 1/4 cup twice daily. He looks and acts so much more healthy now. You should see a weight drop right away if you cut out enough calories. My vet allowed me to bring him in for a weekly weigh in, I would just drop in on off hours and do a quick weight and they would record it for me. You can also add a few green beans to the food or as an occasional snack. But you really need to cut back on the amount of food given and NO FREE FEEDING!