Trim non alphanumeric characters but leave whitespace alon

Hello I'm using the following function and call to remove non alphanumeric characters from a string.

It does do this but also removes white space.

I need to remove all non alphanumeric characters while leaving white space for our product title field of our products table.

How can I adjust my function to leave the white space?

Create Function [dbo].[RemoveNonAlphaCharacters](@Temp VarChar(1000))
Returns VarChar(1000)
AS
Begin

    Declare @KeepValues as varchar(50) = '%[^a-z0-9]%'
    While PatIndex(@KeepValues, @Temp) > 0
        Set @Temp = Stuff(@Temp, PatIndex(@KeepValues, @Temp), 1, '')

    Return @Temp
End

Select allOpen in new window

Select dbo.RemoveNonAlphaCharacters('This and that-:(_)')

returns

Thisandthat