Accessing a function in VB Dll using Vc++/COM

Public Interface ISATExperionPCPlugin
    Function StartAudit(ByVal inputFile As String) As Integer
End Interface
Public Class Exp
    Implements ISATPCPlugin    
    Public Function GetInterface(ByVal interfaceType As Integer, <MarshalAsAttribute(UnmanagedType.IDispatch)> ByRef ppvs As Object) As Integer Implements ISATCommonPlugin.GetInterface
        Dim abc As ISATPCPlugin = New Exp

       '    <need the="" code="" here=""> <need to="" assign="" the="" address="" of="" abc="" ppvs="" so="" that="">
       '                          ppvs->StartAudit(...) can be called from COM>
    
    End Function
    Public Function StartAudit(ByVal inputFile As String) As Integer Implements                          ISATPCPlugin.StartAudit

    End Function
End Class</need></need>

ptrISATPCPlugin->GetInterface(&pluginType,(&IDispatch)**ppvs);
// need the address of abc in ppvs