I am dividing a room by putting up a wall. As a result I need to add heater. My question is it possible for me to add on to the existing run and use this circuit to power the new heater?

Will there be enough power to operate the new heater and does this run a risk of fire.

This is a new home and I am trying to avoid having to add a new home run as this would involve opening a lot of new drywall.

If it is not possible are there any options for heating the new space?

Well... there are a lot of things you have to know before you can do this...
1. what is the capacity of the circuit?
2. how much load is currently on the circuit?
3. how much power does the additional heater draw?
4. will the additional heater overload the existing circuit?

If you are dividing up a room, would two smaller heaters work in place of the one you have now? If two smaller heaters can work, then "PERHAPS" you can do what you suggest. But you have to do a little research first.
Best of luck.