The vaccine, Rotavin-M1, manufactured by POLYVAC-Vietnam, was developed from a G1P [8] strain recovered in 2003 from a child hospitalized for the treatment of acute gastroenteritis

in Nha Trang city (KH0118-2003) [6]. The master and working seeds CAL 101 of this vaccine were produced under GLP conditions using qualified Vero cells and reagents at the US Centers for Disease Control and Prevention (CDC). Pilot vaccine lot, passage 48, was produced by one passage in Vero cells from the working seed, which was provided by the Japanese Polio Research Institute and approved for vaccine production by WHO. These cells have been used for oral poliomyelitis vaccine production at POLYVAC. The master virus seed for Rotavin-M1 was tested for porcine circovirus using real-time RT-PCR at the US CDC and appeared to be free of porcine circovirus DNA. The test for porcine circovirus in pilot vaccine lot was not done. The trials were planned in two stages, the first – a Phase 1 trial

for safety in adult volunteers of a high titer preparation of the vaccine (106.3 FFU/dose). When results of this trial were evaluated by the Data Safety and Monitoring Committee and the vaccine was deemed to be safe for further study in infants, a Phase 1 and 2 adaptive trial was conducted. This trial assessed the safety and immunogenicity of two different preparations of vaccine, one of low titer (106.0 FFU/dose) and Selleckchem Baf-A1 the second with high titer (106.3 FFU/dose) that was administered in either a 2 vs. 3 dose schedules to infants 6–12 weeks of age. A comparison group was included Adenosine of infants who received the lyophilized Rotarix™ vaccine, an established rotavirus vaccine of GSK that was licensed to be used in Vietnam. The study was conducted according to Good Clinical Practice and in accordance with the Declaration of

Helsinki, as amended in Somerset West, Republic of South Africa, in October 1996. The protocol and consent form was reviewed and approved by the Ethical and Scientific Committees of the National Institute of Hygiene and Epidemiology (NIHE) and of the Ministry of Health, Government of Vietnam, prior to initiating the study. The Phase 1 study was conducted in a Career Training School, Thanh Son district, Phu Tho province with a total of 29 healthy adult volunteers 18–49 years of age. Following receipt of informed consent, each of the volunteers was screened by a physician to ensure they were healthy with no active medical problems and asked to provide a blood specimen to test for blood counts and levels of blood urea nitrogen (BUN) and transaminase. The volunteers then each received 2 doses of the high titer vaccine, 106.3 focus-forming units [FFU], at 1-month interval. After administration of each dose of the vaccine, the volunteers were followed daily for 10 days for adverse events and for fecal sample collection. During the next 20 days, the volunteers were followed by phone to ensure they had no sequelae (e.g. diarrhea, vomiting and intussusception).