Promising results for Chikungunya candidate vaccine in phase 1 trial
A chikungunya candidate vaccine developed using noninfectious virus-like particles (VLPs) has been shown to provide long-term protection against multiple genotypes of the disease, according to results of the first human trial, conducted by researchers from the National Institute of Allergy and Infectious Diseases (NIAID) and published today in The Lancet.
The vaccine was given to each of 25 healthy volunteers 18 to 50 years of age in a three-dose regimen of varying strengths (10-, 20-, or 40-mcg) at 0, 4, and 20 weeks. Recipients were followed for 44 weeks.
Neutralizing antibodies were detected in the blood serum of most subjects after the first dose, even those receiving the lowest dosage, and in all subjects after the second dose. Moreover, antibodies were detected after 6 months, and after 11 months were comparable to those reported in people who had recovered after natural chikungunya infection.
The vaccine was well tolerated, with no serious adverse effects reported.
The VLPs used to make the vaccine mimic the immune-stimulating effects of the actual chikungunya virus particles but do not contain any genetic material from the virus so cannot cause infection. In a NIAID press release, lead author Julie Ledgerwood pointed out that the vaccine could be relatively economical to produce, because containment needs would be minimal with the absence of live virus.
Chikungunya is a mosquito-borne disease that is endemic in Africa and in south and southeast Asia. It spread to the Americas in 2013 and is the cause of an ongoing epidemic in the Caribbean comprising some 576,000 cases so far.
Aug 14 Lancet abstract
Aug 14 NIAID press release
Pneumonia and flu clusters at unaccompanied-minor shelters triggers vaccinations
US Centers for Disease Control and Prevention (CDC) investigation into clusters of severe respiratory infections during July in unaccompanied minors from Central America at US resettlement shelters found that several had pneumococcal bacteremia, which is uncommon in US adolescents. Investigators described their findings today in the latest issue of Morbidity and Mortality Weekly Report (MMWR).
On Jul 10 the California Department of Public Health (CDPH) notified the CDC that four boys ages 14 to 16 at the Naval Base Ventura County shelter had respiratory infections, three of them hospitalized with pneumonia. Two were bacteremic with serogroup 5 Streptococcus pneumonia, which is rare in the US adolescents.One of the patients was co-infected with influenza B. The boy who didn't have pneumonia had a 2009 H1N1 influenza infection. At the time, health officials had seen no unusual flu activity in Ventura County.
Between Jul 6 and 19 the CDC learned of clusters of severe respiratory infections at five other sites, totaling 16 cases. The infections occurred at Naval Base Ventura County, Ft. Sill, Okla., Lackland Air Force Base, Tex., a shelter in Houston, and the processing center in Nogales, Ariz.
Of seven cases of lab-confirmed pneumococcal pneumonia, six involved serogroup B. Three youngsters had flu co-infections. Five patients had septic shock, which required treatment in the intensive care unit treatment. Of 11 children tested for flu, four were positive: two had 2009 H1N1 infections, one had influenza B, and one had an influenza A infection based on rapid testing.
Because of the risk of flu and pneumonia in the shelter settings, the CDC recommended that all children in the facilities receive seasonal influenza and Prevnar 13 vaccines alongside routine immunizations. About 2,000 children were immunized, and the shelters reported no adverse events.
The CDC said flu activity in the unaccompanied minor population underscores the importance of influenza vaccination for the population and that Prevnar 13 vaccination is recommended for the group, due to the unexpected number of pneumococcal pneumonia infections occurring in crowded conditions, which could amplify the spread of respiratory viruses and the risk of pneumonia-flu co-infections.
Aug 15 MMWR report
FDA agrees to review Pfizer meningococcal B vaccine
Pfizer announced yesterday that the US Food and Drug Administration (FDA) has agreed to review the company's application for approval of its vaccine against Neisseria meningitidis serogroup B infection and has granted a priority review designation.
Emilio Emini, PhD, senior vice president of vaccine research and development at Pfizer, said in a statement that the FDA's application acceptance and priority review are important milestones in the company's efforts to speed the approval and availability of a meningococcal B vaccine for US adolescents.
Pfizer and Novartis both submitted applications to the FDA for marketing approval of their meningococcal B vaccines on Jul 17. Both are seeking indications for use in young people 10 to 25 years old.
Currently, there is no vaccine in the United States approved for use against serogroup B, which accounted for about 40% of N meningitidis infections in the country in 2012. The lone approved meningococcal vaccine in the United States at present protects against only the four main serogroups: A, C, W-135, and Y.
Outbreaks involving serogroup B occurred on some college campuses in 2013, and nearly 30,000 doses of the Novartis vaccine (Bexsero) were provided to students and staff at Princeton University and the University of California at Santa Barbara under an FDA investigational new drug designation in response to the events.
Aug 14 Pfizer press release
Jun 17 CIDRAP News scan "Companies seek approval for meningococcal serogroup B vaccines"