A multicentric evaluation of recombinant DNA hepatitis B vaccine of Cuban origin

Hepatitis B infection is an important public health problem all over the world. As no specific treatment is available, greatest emphasis is placed on prevention through immunization.

To evaluate the immunogenicity (sero-protection rate) and reactogenicity of a novel recombinant DNA hepatitis B vaccine of Cuban origin (Enivac HB).

The study was conducted at two independent centres (New Delhi and Jaipur) and 111 healthy volunteers without any symptomatic or serological evidence of HBV infection were administered the vaccine intramuscularly in a dose of 20 ug at day 0, day 30 and day 180. Blood samples were collected for evaluation of sero-protection on days 30, 60, 90 and 210 at both centres and, in addition, at day 120 at New Delhi. All subjects were evaluated for any adverse event for 120 hours subsequent to each dose of the vaccine.

The mean age of the volunteers was 24 years and the male:female ratio was 61:50. An overall sero-protection rate of 24.3% was obtained at day 30, 68.5% at day 60, 94.5% at day 90 and 99.1% by day 120. Following the third dose of the vaccine (at day 180), we lost one subject to follow up and further evaluation could be done in a total of 110 volunteers. The sero-protection rate by day 210 was found to be 100% (110/110). The vaccine was well tolerated with no serious adverse reactions. Minor side effects such as injection site tenderness, erythema and/or low grade fever were observed in 4.5% of the subjects.

The recombinant DNA hepatitis B vaccine of Cuban origin is safe, well tolerated and highly immunogenic.