CMV Vaccine in the Works
Vaccine May Help Prevent Birth Defects Caused by Cytomegalovirus
March 18, 2009 -- An experimental vaccine may curb cytomegalovirus (CMV) in
women, which might reduce CMV-related birth defects in their children.
That’s according to a new study, published in The New England Journal of
CMV is common and it doesn't typically show symptoms in adults. It can pass
from mother to fetus, making birth defects -- including hearing problems --
According to the CDC, CMV is the most common virus transmitted to a pregnant
woman's fetus. About one in 150 children is born with CMV infection, and about
one in 750 U.S. children is born with or develops permanent disabilities
because of CMV.
CMV Vaccine Study
The new CMV vaccine study included 464 women 14-40 in Alabama. When the
study started, none of the women were pregnant and none had a history of CMV.
The researchers gave the women three shots of the experimental CMV vaccine
or a placebo.
During the next three years, 8% of the women who had gotten the CMV vaccine
developed CMV infection, compared to 14% of women who had gotten the placebo
"Vaccine efficacy was 50%," write the researchers, who included
Robert Pass, MD, of the pediatrics department at the University of Alabama at
Injection site reactions, chills, joint pain, and muscle pain were more
common in the vaccine group than in the placebo group.
Most adverse events were mild and temporary. But one woman in the vaccine
group had a fever, rash, muscle pain, and weakness that left her unable to walk
after the second dose of the vaccine; she recovered over the next six to seven
months. Another woman who had gotten the placebo shots had numbness in her feet
and hands 10 weeks after the second dose; her symptoms improved with time. It's
not clear what caused those symptoms.
Fifteen babies, who were conceived three to 40 months after the last shots
were given, had serious adverse events. Seven of those babies were born to
women who had gotten the experimental vaccine.
Further studies are needed, the researchers note. They point out that CMV is
a "large and complex virus" and that people who've had CMV infection
can become infected by new CMV strains.
"The development of a CMV vaccine remains a daunting task," states
an editorial published with the study. "Even so, the prevention of the
burden of congenital CMV infection -- despite all the challenges -- must remain
a high priority," write editorialists Cornelia Dekker, MD, and Ann Arvin,
MD, of Stanford University School of Medicine.
The CMV study was funded in part by Sanofi Pasteur, which makes the
experimental CMV vaccine.
Researcher Pass and several colleagues report financial ties to various drug
companies and partial interest in relevant patents. Editorialist Arvin reports
receiving consulting fees from the drug companies Merck and