At 96 weeks , 289 ( 900 % ) of 321 patients in the efavirenz 400 mg group and 280 ( 906 % ) of 309 in the efavirenz 600 mg group had a plasma HIV-1 viral load less than 200 copies per mL ( difference -06 , 95 % CI -52 to 40 ; p = 072 ) , which suggests continued non-inferiority of the lower efavirenz dose .