Pharmacokinetics and Safety of Bupivacaine HCl Spinal Block and EXPAREL Local Infiltration in Total Knee Arthroplasty

On Day 1, following an epinephrine "wash" of the spinal block syringe, eligible subjects
will receive a single 1.6 mL dose of bupivacaine HCl 7.5 mg/mL within 2 hours prior to the
surgical procedure as a spinal block. EXPAREL 266 mg in 20 mL (expanded with 70 mL of
preservative-free sterile normal saline to a total volume of 90 mL) will be infiltrated into
the surgical site at the end of the surgery prior to wound closure. There will be no local
co-administration of the two drugs.

Blood samples for bupivacaine PK analysis will be obtained from subjects at baseline (prior
to bupivacaine HCl administration for nerve block), 15 minutes, 30 minutes, and 1, 2, 4, 8,
12, 24, 48, and 72 hours after the beginning of EXPAREL administration, and on Day 14.

Inclusion Criteria:

1. Males or females ≥18 years of age.

2. American Society of Anesthesiologists (ASA) physical status 1, 2, or 3.

3. Scheduled to undergo spinal block in conjunction with unilateral TKA.

4. Female subjects must be surgically sterile, at least 2 years postmenopausal, or using
a medically acceptable method of birth control. Females of childbearing potential
must have a documented negative blood or urine pregnancy test result within 24 hours
before surgery.

5. Able to provide informed consent, adhere to the study schedule, and complete all
study assessments.

Exclusion Criteria:

1. History of hypersensitivity or idiosyncratic reactions to amide-type local
anesthetics or opioids.

2. Contraindication to bupivacaine.

3. Received bupivacaine or any other local anesthetic within 7 days of EXPAREL
administration.

4. Currently pregnant, nursing, or planning to become pregnant during the study or
within 1 month after EXPAREL administration.

5. Planned concurrent surgical procedure (e.g., bilateral TKA).

6. Body weight <50 kg (110 pounds) or a body mass index ≥45 kg/m2.

7. Received any investigational drug within 30 days prior to EXPAREL administration,
and/or has planned administration of another investigational product or procedure
during the subject's participation in this study.

8. Previous participation in an EXPAREL study.

9. Malignancy in the last 2 years, with the exception of non-metastatic basal cell or
squamous cell carcinoma of the skin or localized carcinoma in situ of the cervix.

10. Current or historical evidence of any clinically significant disease or condition,
especially cardiovascular or neurological conditions that, in the opinion of the
Investigator, may increase the risk of surgery or complicate the subject's
postsurgical course.

11. Clinically significant medical or psychiatric disease that, in the opinion of the
Investigator, would constitute a contraindication to participation in the study, or
cause inability to comply with the study requirements.

In addition, the subject will be ineligible to receive EXPAREL if he or she meets the
following criteria during surgery:

12. Any clinically significant event or condition uncovered during the surgery (e.g.,
excessive bleeding, acute sepsis) that might render the subject medically unstable or
complicate the subject's postsurgical course.