- Failed prior amprenavir therapy, whether on ACTG 347 or not, i.e., HIV RNA greater than or equal to 500 copies/ml after at least 16 weeks of amprenavir and confirmed within 1-6 weeks OR treatment failure that mandated early permanent discontinuation of randomized ACTG 347 study drugs and defined as HIV RNA of at least one log 10 above the nadir (to at least 5,000 copies/ml) or HIV RNA level above the baseline value before 16 weeks of amprenavir and confirmed within 1-6 weeks.