Replacing the Value of a particular Dropdownlist Item

[Jason]

The following code removes a particular item from my drop down.

Instead, I would like to replace it's value with another string. How
can I do that in vb.net?

Dim ddl = CType(FormMaint.FindControl("OfferCodesDropDown"),
DropDownList)
If sender.selectedvalue < 10 Then
ddl.Items.Remove(ddl.Items.FindByValue("BUY NOW"))
Else
'???
End If

Thanks.