Clogged cartridge filters and the trial failure they likely caused battered shares of Windtree Therapeutics Inc. (OTCQB:WINT), sending the stock falling 61.8 percent Friday, or 53 cents, to close at 33 cents on news that its aerosolized medicine for preemies with respiratory distress syndrome, Aerosurf, failed to diminish the need for intubation, missing the trial's primary endpoint.