LONDON – Shares in Akari Therapeutics plc (NASDAQ:AKTX) shot up 224 percent to close at $5.90 per share Wednesday, with shares changing hands at nearly 3,000 times the average volume, after the company announced it has FDA approval for a pivotal trial of Coversin in pediatric thrombotic microangiopathy (TMA), a frequently fatal complication of bone marrow transplants.