** Shares of drugmaker Tonix Pharmaceuticals TNXP.O rise 4.6% to $13.11 premarket

** Co says it secured Medicare coverage for Tonmya, its approved treatment for fibromyalgia, a chronic disorder marked by widespread pain, fatigue and sleep problems

** Agreement will expand access to about 9 million Medicare patients starting January 1, 2027, TNXP says

** TNXP says Tonmya will then be covered for about 145 million Americans, including through previously announced commercial insurance deals and Medicaid programs

** Co says it is continuing talks with other Medicare and commercial insurers

** Co adds it is expanding its sales force, adding 50 representatives to bring the team to about 150

** As of last close, TNXP down 19.8% YTD