A Study of Live Oral Cholera Vaccine, PXVX200 in Healthy Older Adults

Inclusion Criteria:

- healthy men or women,

- age 46 to 64 years inclusive;

- normal medical history and physical examination

- Women must have a negative pregnancy test

Exclusion Criteria:

- travel to a cholera endemic area in the previous 5 years;

- abnormal stool pattern or regular use of laxatives;

- Currently active unstable or undiagnosed medical conditions

- current or recent antibiotic use;

- pregnancy or nursing;

- Previously received a licensed or investigational cholera vaccine

- History of cholera or enterotoxigenic E. coli infection

- History of Guillain-Barré Syndrome

- Received or plans to receive any other licensed vaccines, except for seasonal
influenza

- Recipient of bone marrow or solid organ transplant

- Malignancy (excluding non-melanotic skin cancers) or lymphoproliferative
disorders diagnosed or treated during the past 5 years

- Use of systemic chemotherapy in the previous 5 years prior to the study

- any immunosuppressive medical condition