Reverse gst charges for rent paid by r d to urd.

Your company give pure medical services then you don't want register under GST. As your position is URD then you don't pay Tax under RCM for the Rent...
If you are registered and the landlord is URD then you ll be pay Tax under RCM basis.
The rent is Rs 100000 you pay Tax @ 18% (18000). It ll be pay on time of transaction or time of payment....
Also you can adjust the tax amount as ITC. You don't have any liabilities then you can claim it as refund......

Thank you very much Sir .  But how do we get the refund ? As Income Tax Refund or any other way ?

No. Income Tax is not under this category...
You read GST refund related articles or law. then follow the way....