ATLANTA -- The CDC's voted unanimously to recommend the newly FDA-approved cholera vaccine for use in adult travelers to areas with active cholera transmission.
This was a grade A recommendation (for all persons in an age or risk-factor based group) of the CVD 103-HgR vaccine (Vaxchora), which the FDA recently approved for preventing cholera serogroup O1 among adults 18-64 years old.
In February, clinical trials of the CDV 103-HgR vaccine were presented here by vaccine manufacturer PaxVax Bermuda, which found a vaccine efficacy rate of 79.5% after 3 months for protection against severe (>3 L) diarrhea, and that the rate of seroconversion was 90.4% after 180 days. The ACIP cholera working group then found the vaccine safe and effective for prevention of toxigenic Vibrio cholerae O1 in a GRADE evaluation.
The committee voted to recommend both preventive measures, as well as the vaccine for prevention against severe cholera among travelers. They emphasized that the vaccine was not routinely recommended for most travelers and that clinicians take a "detailed assessment of traveler's risk of exposure and risk of severe outcomes" prior to recommendation.
"Personal protective measures" included safe food and water precautions and personal hygiene measures for preventing cholera infection.
This vaccine is a newer formulation of a CDV 103-HgR vaccine that was previously administered to over 500,000 persons before the manufacturer discontinued the vaccine for business reasons.
Originally, the working group recommended this vaccine for an extensive list of populations who were either at increased risk of acquiring severe cholera or had an increased risk of poor clinical outcomes from the disease. After discussion among committee members, it was determined that this could be too confusing to clinicians, and that all travelers to areas with active cholera transmission should receive the vaccine.
The working group found no data on the safety or efficacy of this vaccine among pregnant patients, immunocompromised persons or children, but the FDA approval for the vaccine noted that safety and efficacy was not established for immunocompromised persons, persons <18 years or ≥65 years. A pregnancy exposure registry was also established.
HIV-Infected Persons Should Routinely Receive MenACWY Vaccine
The ACIP also voted unanimously to recommend that HIV-infected persons ages ≥2 months receive the meningococcal conjugate ACWY vaccine. Another unanimous vote approved the addition of the meningococcal conjugate vaccines (MenACWY and HibMenCY) for HIV-infected children >2 months of age to the federally-funded program.
"ACIP does not currently include HIV infected persons in recommendations for routine vaccination for persons at increased risk of meningococcal disease," said , of the CDC, in a presentation prior to the vote.
The committee recommended a two-dose primary series of the vaccine for HIV-infected persons ages ≥2 years who had not been previously vaccinated, and that those who had been previously vaccinated receive a second dose at the earliest opportunity, and then continue to receive boosters.
There are currently three manufacturers of meningococcal conjugate vaccines approved for use in both children and adults. Two are for MenACWY: Menactra (Sanofi Pasteur), Menveo (NovartisVaccines/GSK), and one for serogroups C and Y, and Haemophilus influenzae type B: MenHibrix (GSK)
The working group found what they characterized as "a growing body of evidence" about the risk of meningococcal disease for people with HIV. Five studies showed that HIV-infected persons had a five- to 24-fold increased risk of acquiring meningococcal disease.
There was no safety or immunogenicity data for meningococcal disease serogroup B in persons with HIV, so it was not included in the recommendation, as the working group found that the risk was mainly from serogroups C, W, and Y.
The committee concluded that about 50% of the one million persons living with HIV in the U.S. receive regular HIV care at HIV clinics, and would be more likely to have CD4 counts and viral loads "favorable for immunogenicity."
An alternate proposal was to begin routine MenACWY vaccination for HIV-infected persons ≥11 years of age, but the majority of the working group felt that the recommendation to include younger children would not be "burdensome," due to the small number of HIV-infected children in the U.S. They added that hSBA titers for HIV-infected children ages 2-10 years is higher than in HIV-infected adolescents ages 11-24 years.
An earlier presentation on the cost effectiveness of the MenACWY vaccine among this population found that routine vaccination of those infected with HIV would be "relatively costly," mainly due to the relatively low numbers of disease cases and deaths, and the high cost of lifelong booster doses. However, this analysis also concluded that additional cases could be prevented by all vaccination strategies.