Simplify code

Hey

Is it possible to simplify this code:

Do While ActiveCell.Value = "O" Or ActiveCell.Value = "T" Or ActiveCell.Value = "A"
            If ActiveCell.Value = "O" Or ActiveCell.Value = "T" Or ActiveCell.Value = "A" Then
            ActiveCell.Offset(1, 0).Select
            Else: Exit Sub
            End If
        Loop

I want to make an efficient (fast) code, but this looks terrible. ....any suggestions?