Sarepta Therapeutics’ stock soars 38% after FDA expands use of its Duchenne muscular-dystrophy drug
				
																	
								
				Sarapeta Therapeutics Inc.’s stock soared 38% in premarket trade Friday, after the biotech said the U.S. regulator has approved an expanded indication of its treatment for the rare muscle disorder Duchenne muscular dystrophy.				
			
			
			
			
						
						
						
					
		