Define a new family using the Revit Metric Generic Model face based family template.

C:\ProgramData\Autodesk\RVT 2015\Family Templates\English Imperial\Generic Model face based.rft

Save it as a new custom family

C:\ProgramData\Autodesk\RVT 2015\Libraries\PS\Doors\Fittings\ dh1.rfa

Assign the correct Revit Family category and parameters. To do this click on

Select and accept the default parameters and click

This allows us to assign the components we create in this family to the sub-categories of the door family.
Create an extrusion as follows (viewed from the Floor Plan)

Viewed from the Front Elevation:

Create the following reference lines on the plane in Revit.

Viewed in 3D

Sweep a circular profile along the path defined by the reference lines.

Set the sub-categories of the components created appropriately.

Chances are this handle will not be made of the same material as the panel it is hosted on, so create a material type parameter for the family. I assigned a polished stainless steel material to this parameter.

Assign the material parameter to the handle shapes.

Save the file.