A Study to Evaluate the Effect of SYN-004 on the PK of IV Ceftriaxone in Adults With a Functioning Ileostomy

This is a Phase 1b/2a, randomized, multi-center, open-label study. Twenty otherwise healthy
subjects between the ages of 18 and 80 years, inclusive, with functioning ileostomies were
planned to be enrolled. In the first treatment period (Period 1) all subjects received an IV
infusion of 1 g ceftriaxone. Subjects had a 3 - 7 day washout period between Period 1 and
Period 2. In the second treatment period (Period 2) all subjects received an IV infusion of 1
g ceftriaxone and 2 oral doses of either 75 or 150 mg of SYN-004, according to the
randomization schedule, which were administered 30 minutes before and 5.5 hours after the
start of the ceftriaxone infusion.

Inclusion Criteria:

1. The subject has a functioning ileostomy which has been in place for > 3 months.

2. Male or female between the ages of 18 and 70 years, inclusive.

3. Other than a functioning ileostomy, the subject is free from clinically significant
illnesses or disease.

Exclusion Criteria:

1. Subjects who have active hepatic, small intestine, or biliary tract disease.

2. Subjects who have active ulcerative colitis, Crohn's disease, other inflammatory bowel
disease.

3. Subjects with known malignancy requiring treatment < 6 months prior to study
screening.

4. Subjects who have, in the opinion of the investigator, significant concurrent medical
illness.

5. Subjects who are currently taking concomitant medications which may interfere with
study evaluation.

6. Subjects who have received an investigational drug within 30 days or within a time
period consistent with a washout period of 5 half-lives, whichever is longer, of the
first dose of ceftriaxone.

7. Subjects with a known history of allergy to any cephalosporin, penicillin or any
β-lactam antibiotic.

8. Subjects who have known active malabsorption syndromes(s) that, in the judgment of the
investigator, could compromise the objectives of the study.

9. Subjects who have used any oral, intramuscular, or IV anti-microbial medication during
the last 3 weeks prior to the screening visit.