WASHINGTON (AP) — U.S. health advisers have narrowly ruled against an experimental drug for the debilitating illness known as Lou Gehrig’s disease. Wednesday’s vote by the Food and Drug Administration expert panel is a potential setback for patient groups who have lobbied for the medication’s approval for ALS for more than a year. A majority of panelists agreed with a negative review published by FDA scientists earlier in the week. Some said they hoped results of a larger study now underway would provide more evidence of the drug’s effectiveness. The panel’s vote is non-binding and the FDA will make its final decision by July.