Roche Holding AG said Friday that the Food and Drug Administration had approved Evrysdi, a treatment for spinal muscular atrophy in adults and most children. It’s the second drug to be approved by the regulator to treat the rare disease. The therapy was developed by PTC Therapeutics Inc. and will be marketed by Genentech, a division of Roche. “We believe Evrysdi, with its favorable clinical profile and oral administration, may offer meaningful benefits for many living with this rare neurological disease,” Roche’s Levi Garraway said in a news release. A spokesperson said in an email that the treatment will cost about $340,000 per year, which is a lower price point than Biogen’s Spinraza and AveXis Inc.’s Zolgensma; however the lower-than-expected price “could help increase market share and rapidity of adoption, though will produce lower revenue per patient than we had estimated,” RBC Capital Markets’ Brian Abrahams wrote in a note to investors. Since the start of the year, PTC’s stock is down 0.4%, shares of Roche have gained 6.2%, and the S&P 500 is up 3.7%.Market Pulse Stories are Rapid-fire, short news bursts on stocks and markets as they move. Visit MarketWatch.com for more information on this news.