I have an english ivy topiary. I purchased it in January it was beautiful. Since then it is steadily loosing his leaves. I have repotted it but the water runs right through to the bottom container. I don't know what to do.

The soil could be too "airy" so the water is running straight through without the roots or root-ball absorbing much of the water. If the root-ball way down looks or feels dry right after watering, that's probably why your losing so many leaves. It might even need a slightly bigger pot? (one size up) with more soil around the roots.
Make sure the soil is not pulled away from the sides where water can run right out, add soil if you need to all around the sides.
Water until it looks like it might come over the sides, then let it drain out and get rid of the excess.Let the soil get almost close to dry, just not completely dry.
Give it bright light, but no direct sun. Also keep an eye out for spidermites on this plant.It's a good idea to also spray off the leaves when watering.