Requires treatment with a strong cytochrome P CYPA/ inhibitor Unable to discontinue use of a strong CYPA inhibitor Subjects who require therapy with a strong CYPA inhibitor prior to enrollment to this study The use of strong CYPA inhibitor (with the exception of ketoconazole). Received a strong cytochrome P (CYP) A inhibitor or inducer within days prior to the first dose of ibrutinib, OR subjects who require continuous treatment with a strong cytochrome P CYPA inhibitor or inducer Subjects who received a strong cytochrome P A (CYPA) inhibitor within days prior to the first dose of ibrutinib or subjects who require continuous treatment with a strong CYPA inhibitor Subjects who received a strong cytochrome P (CYP) A inhibitor within days prior to the first dose of ibrutinib or subjects who require continuous treatment with a strong CYPA inhibitor Subjects who received a strong cytochrome P A (CYPA) inhibitor within days prior to the first dose of ibrutinib or subjects who require continuous treatment with a strong CYPA inhibitor Subjects who received a strong cytochrome P (CYP) A inhibitor within days prior to the first dose of ibrutinib or subjects who require continuous treatment with a strong CYP A inhibitor Patients who received a strong cytochrome P (CYP) A inhibitor within days prior to the first dose of ibrutinib or patients who require continuous treatment with a strong CYPA inhibitor with the exception of voriconazole, which will be specifically studied in this protocol Chronic treatment (i.e. > days) with a strong Cytochrome P (CYPA) inhibitor which cannot be terminated prior to the first dose of ibrutinib. Patients who received a strong cytochrome P (CYP) A inhibitor within days prior to the first dose of ibrutinib or patients who require continuous treatment with a strong CYPA inhibitor Concomitant treatment with strong cytochrome P A/cytochrome P A (CYPA/) inhibitor Subjects who received a strong cytochrome P family subfamily A (CYPA) inhibitor within days prior to the first dose of study drug, or patients who require continuous treatment with a strong CYPA inhibitor are not eligible Use of a strong CYPA inhibitor within three elimination half-lives of the inhibitor prior to the start of study treatment. Patients who received a strong cytochrome P (CYP) A inhibitor within days prior to the first dose of ibrutinib or patients who require continuous treatment with a strong CYPA inhibitor Concurrent use of a strong CYPA inhibitor. Subjects who have received a strong CYPA inhibitor prior to entering the study must have discontinued therapy for at least half lives of the prohibited medication. Requirement for medication with strong CYPA inhibitor