RegEx pattern

Why RegExp?

Just replace ", Other (please specify)" with "" should do....

If you insist

Sub test()
    Dim r As Range
    With CreateObject("VBScript.RegExp")
        .Pattern = "(.+)(?=(, Other \(please specify\)))"
        For Each r In Range("a1", Range("a" & Rows.Count).End(xlUp))
            If .test(r.Value) Then r.Value = .Execute(r.Value)(0)
        Next
    End With
End Sub