- Female patients must be of non child-bearing potential or use effective contraception, e.g., use of oral contraceptives with an additional barrier method (since the study drug may impair the effectiveness of oral contraceptives), double barrier methods (diaphragm with spermicidal gel or condoms with contraceptive foam), Depo-Provera, partner vasectomy, total abstinence, and willing to continue the effective contraception method for 30 days after the last dose of AVX901;