Immunoglobulin Doesn't Boost HBV Vaccine Prophylaxis in Newborns of Infected MothersBy: DIANA MAHONEY, Internal Medicine News Digital Network

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Gastroenterology

Immunoglobulin Doesn't Boost HBV Vaccine Prophylaxis in Newborns of Infected

MothersBy: DIANA MAHONEY, Internal Medicine News Digital Network

12/01/10

BOSTON – The recombinant hepatitis B vaccine confers as much protection when

given alone as it does when given together with hepatitis B immunoglobulin to

newborns of chronically infected mothers, but neither regimen is optimally

effective, a study has shown.

The randomized controlled trial assessed the hepatitis B virus (HBV) status of

222 infants born to mothers who tested positive for hepatitis B surface antigen

(HBsAg). The rate of protection observed in infants who received only the

vaccine was statistically similar to that of infants who received the vaccine

plus hepatitis B immune globulin (HBIG).

A total of 39% of the vaccine-only group and 41% of the combination group

remained infection free at a minimum of 18 weeks after birth, Dr. Shiv K. Sarin

reported at the annual meeting of the American Association for the Study of

Liver Diseases, noting that nearly half of the babies in both groups developed

occult HBV infections.

The current standard of care for preventing HBV infection in babies born to

mothers who are HBsAg positive is the recombinant hepatitis B virus vaccine plus

HBIG, however previous studies have suggested the possibility that the vaccine

alone may be as effective as the combination therapy, said Dr. Sarin of the

Institute of Liver and Biliary Sciences in New Delhi.

To test this hypothesis, Dr. Sarin, along with lead investigator Dr. Chandana

Pande, a research associate at G.B. Pant Hospital in New Delhi, and colleagues

randomized the newborns of 222 women who screened positive for HBsAg during

their prenatal care to receive the 0.5-mL recombinant HBV vaccine at birth, 6

weeks, 10 weeks, and 14 weeks, either alone (116 infants) or with 0.5 mL

intramuscular HBIG (106 infants). Mothers on antiviral therapy and those with

coinfections were excluded from the investigation, he said.

All of the babies were assessed at a minimum of 18 weeks for HBsAg, HBV-DNA, and

antibodies to HBsAg (anti-HBs). The study’s primary end point was freedom from

overt or occult HBV infection with adequate immune response, defined as anti-HBs

titers of at least 10 IU/mL, Dr. Sarin said in a poster presentation.

Babies with overt HBV infection were those whose blood specimens tested positive

for HBsAg by enzyme-linked immunosorbent assay, whereas babies with occult

infection were negative for HBsAg but positive for HBV-DNA by polymerase chain

reaction testing, he said. Babies with no infection but whose anti-HBs titers

were less than 10 IU/mL were categorized as having a poor immune response.

At 18 weeks after birth, there were no significant differences between the

combination therapy group and monotherapy group with respect to the number of

babies meeting the study’s primary end point, Dr. Sarin reported. Specifically,

43 babies in the combination group and 45 in the vaccine-only group remained

free of overt or occult HBV infection with adequate immune response, he said.

Of the babies not meeting the primary end point, 9 had overt HBV infection,

including 2 in the combination group and 7 in the vaccine-only group, and 106

developed occult HBV infection, including 52 in the combination group and 54 in

the vaccine-only group, Dr. Sarin said. Neither of these differences attained

statistical significance, nor did the between-group difference in the number of

infants demonstrating a poor immune response, he said. Nineteen babies in the

combination group and 10 in the vaccine-only group had anti-HBs titers lower

than 10 IU/mL.

The large number of babies in both groups who developed occult HBV infection

" may be due to intrauterine transmission of the infection, " Dr. Sarin suggested.

The findings highlight the need for trials of antiviral agents during pregnancy

in order to prevent cases in which immunoprophylaxis strategies need to be used,

but then fail, he stressed.

Dr. Sarin and Dr. Pande said they had no relevant financial disclosures.

[Guest guest]

http://www.internalmedicinenews.com/news/gastroenterology/single-article/immunog\

lobulin-doesn-t-boost-hbv-vaccine-prophylaxis-in-newborns-of-infected-mothers/3a\

739bcf5d.html

Gastroenterology

Immunoglobulin Doesn't Boost HBV Vaccine Prophylaxis in Newborns of Infected

MothersBy: DIANA MAHONEY, Internal Medicine News Digital Network

12/01/10

BOSTON – The recombinant hepatitis B vaccine confers as much protection when

given alone as it does when given together with hepatitis B immunoglobulin to

newborns of chronically infected mothers, but neither regimen is optimally

effective, a study has shown.

The randomized controlled trial assessed the hepatitis B virus (HBV) status of

222 infants born to mothers who tested positive for hepatitis B surface antigen

(HBsAg). The rate of protection observed in infants who received only the

vaccine was statistically similar to that of infants who received the vaccine

plus hepatitis B immune globulin (HBIG).

A total of 39% of the vaccine-only group and 41% of the combination group

remained infection free at a minimum of 18 weeks after birth, Dr. Shiv K. Sarin

reported at the annual meeting of the American Association for the Study of

Liver Diseases, noting that nearly half of the babies in both groups developed

occult HBV infections.

The current standard of care for preventing HBV infection in babies born to

mothers who are HBsAg positive is the recombinant hepatitis B virus vaccine plus

HBIG, however previous studies have suggested the possibility that the vaccine

alone may be as effective as the combination therapy, said Dr. Sarin of the

Institute of Liver and Biliary Sciences in New Delhi.

To test this hypothesis, Dr. Sarin, along with lead investigator Dr. Chandana

Pande, a research associate at G.B. Pant Hospital in New Delhi, and colleagues

randomized the newborns of 222 women who screened positive for HBsAg during

their prenatal care to receive the 0.5-mL recombinant HBV vaccine at birth, 6

weeks, 10 weeks, and 14 weeks, either alone (116 infants) or with 0.5 mL

intramuscular HBIG (106 infants). Mothers on antiviral therapy and those with

coinfections were excluded from the investigation, he said.

All of the babies were assessed at a minimum of 18 weeks for HBsAg, HBV-DNA, and

antibodies to HBsAg (anti-HBs). The study’s primary end point was freedom from

overt or occult HBV infection with adequate immune response, defined as anti-HBs

titers of at least 10 IU/mL, Dr. Sarin said in a poster presentation.

Babies with overt HBV infection were those whose blood specimens tested positive

for HBsAg by enzyme-linked immunosorbent assay, whereas babies with occult

infection were negative for HBsAg but positive for HBV-DNA by polymerase chain

reaction testing, he said. Babies with no infection but whose anti-HBs titers

were less than 10 IU/mL were categorized as having a poor immune response.

At 18 weeks after birth, there were no significant differences between the

combination therapy group and monotherapy group with respect to the number of

babies meeting the study’s primary end point, Dr. Sarin reported. Specifically,

43 babies in the combination group and 45 in the vaccine-only group remained

free of overt or occult HBV infection with adequate immune response, he said.

Of the babies not meeting the primary end point, 9 had overt HBV infection,

including 2 in the combination group and 7 in the vaccine-only group, and 106

developed occult HBV infection, including 52 in the combination group and 54 in

the vaccine-only group, Dr. Sarin said. Neither of these differences attained

statistical significance, nor did the between-group difference in the number of

infants demonstrating a poor immune response, he said. Nineteen babies in the

combination group and 10 in the vaccine-only group had anti-HBs titers lower

than 10 IU/mL.

The large number of babies in both groups who developed occult HBV infection

" may be due to intrauterine transmission of the infection, " Dr. Sarin suggested.

The findings highlight the need for trials of antiviral agents during pregnancy

in order to prevent cases in which immunoprophylaxis strategies need to be used,

but then fail, he stressed.

Dr. Sarin and Dr. Pande said they had no relevant financial disclosures.