The purpose of this study is to assess the potential effects of rifampin on the pharmacokinetics (how the drug concentrations change over time) of PCI-32765 in healthy participants.

This is an open-label (all people know the identity of the intervention), single center (study conducted at one site), sequential study (it is a design in a single group of participants are administered one or more study medication in a sequence) to evaluate the potential effects of rifampin on the pharmacokinetics of PCI-32765 in healthy participants.The study consists of 3 phases: screening phase (21 days prior to first dose of study medication), treatment phase (14 days), and a follow up phase (10 to 12 days after the last dose of study medication). In the treatment phase, a single dose of PCI-32765 560 mg will be administered orally on Day 1 and Day 11. Rifampin 600 mg (2 X 300 mg) will be administered orally on Days 4 to 13; followed by a single dose of PCI-32765 on Day 11. Follow up will be continued until Day 14. Safety evaluations for adverse events, clinical laboratory tests, electrocardiogram, vital signs, and physical examination will be monitored throughout the study. The duration of the study will be approximately for 45 days.

Inclusion Criteria:

• Participants should be healthy on the basis of physical examination, medical history, vital signs, electrocardiogram, the results of blood biochemistry and hematology tests and a urinalysis performed at screening
• Agrees to protocol-defined use of effective contraception

Exclusion Criteria:

• Participants with medically significant cardiac disease, hematologic, lipid abnormalities, significant pulmonary disease (bronchospastic respiratory), diabetes mellitus, renal or hepatic insufficiency, thyroid disease, neurologic or psychiatric disease and infectious disease
• Abnormal clinical laboratory and physical examination and vital signs
• Use of any prescription or nonprescription medication (including vitamins and herbal supplements), except for acetaminophen, within 3 days before the first dose of the study drug is scheduled
• Positive to human immunodeficiency virus-type 1 (HIV-1) or HIV-2 test and hepatitis A, B or C infection at screening