Safety and Efficacy Study of VP20621 for Prevention of Recurrent Clostridium Difficile Infection

Inclusion Criteria:

1. Adult subjects, 18 years of age and over, who understand the risks and benefits of
participation and have provided written informed consent for the study.

2. Subjects who are experiencing a first event or first recurrence of clostridium
difficile (CDI) within the last 28 days and have been successfully treated with an
antibiotic for CDI.

3. Subjects who are medically stable.

4. Subjects who are willing and able to comply with the study procedures and visit
schedules outlined.

5. If female be post-menopausal, surgically sterile or agree to follow an acceptable
method of birth control.

Exclusion Criteria:

1. Subjects who have had more than 2 episodes of CDI within the last 6 months.

2. Subjects who have been diagnosed with Inflammatory Bowel Disease,active Irritable
Bowel Syndrome, celiac disease, active gastroparesis, toxic megacolon.

3. GI surgery within 6 weeks before the day of randomization

4. Have known immunodeficiency disorder, such as HIV Infection

5. Pregnant or breast feeding females.

6. Concurrent acute life-threatening diseases.

7. Inability to tolerate oral liquids.

8. Have an absolute neutrophil count < 1000/mm3 at screening