Vaccine Info

CHIKV-VLP Chikungunya Vaccine

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Last reviewed
February 15, 2023

CHIKV-VLP (Chikungunya) Vaccine 2023

Bavarian Nordic A/S chikungunya adjuvanted single dose CHIKV-VLP vaccine candidate (PXVX0317) is an aluminum hydroxide-adjuvanted chikungunya virus-like particle vaccine (VLP) with a multi-protein structure that mimics the organization and conformation of naturally occurring viruses without the viral genome, promoting a stronger immune response and increased antibody production. Chikungunya studies have shown that VLP vaccines are highly immunogenic, have a proven safety record, and typically elicit high titer neutralizing antibodies needed to protect against the chikungunya virus.

The chikungunya CHKV-VLA vaccine candidate received the U.S. Food and Drug Administration (FDA) Fast Track designation in May 2018 and the European Medicines Agency (EMA) PRIME designation in January 2020. In addition, the chikungunya CHIKV VLP vaccine candidate is licensed from the National Institute of Allergy and Infectious Diseases at the National Institutes of Health.

In November 2019, study results indicated that up to 98% of study participants produced a neutralizing antibody response against the chikungunya virus within seven days after vaccination after a single dose. Further, the immune response persisted for at least one year for subjects who received a single dose. The vaccine candidate was well-tolerated across all study arms, and no significant vaccine-related safety concerns have been identified in analyses to date. Solicited adverse event profiles were similar across groups and primarily mild or moderate.

On May 26, 2021, phase 2 study results: "Emergent is pleased with the positive data from our Phase 2 CHIKV VLP study that demonstrated safety and immunogenicity two years post-vaccination with a single adjuvanted 40 µg dose of the CHIKV VLP vaccine, which we believe is an ideal candidate to evaluate in a Phase 3 study that we intend to initiate this year," said Karen L. Smith, M.D., Ph.D., EVP and CMO at Emergent BioSolutions.

The Lancet Infectious Diseases published a research article on June 13, 2022:  Safety and immunogenicity of PXVX0317, an aluminum hydroxide-adjuvanted chikungunya virus-like particle vaccine: a randomized, double-blind, parallel-group, phase 2 trial. On June 21, 2022, Emergent announced the CHIKV VLP vaccine candidate was found in a phase 2 study to be well tolerated and induce a robust and durable serum-neutralizing antibody immune response against the Chikungunya virus for up to two years. And on November 1, 2022, the Company announced results from a Phase 2 study that demonstrated the CHIKV VLP vaccine candidate was well-tolerated and immunogenic in alphavirus vaccine-naïve participants and participants previously vaccinated against the Venezuelan equine encephalitis virus. 

European Medicines Agency (EMEA-002656-PIP01-19), U.S. Food and Drug Administration (FDA) Briefing Document, November 8, 2019.

Gaithersburg, Maryland-based Emergent BioSolutions sold this vaccine to Bavarian Nordic A/S on February 15, 2023.

Chikungunya Vaccine Candidates 2023

In the U.S., the Food and Drug Administration has not approved any chikungunya vaccine candidate as of January 29, 2023.

CHIKV-VLP Indication

The CHIKV-VLP vaccine candidate is indicated to prevent infections of the chikungunya virus. The Chikungunya virus is spread to people through infected mosquitoes. Symptoms lasting 3-4 weeks include high-grade fever, joint pain, headache, muscle pain, joint swelling, or rash, while chronic arthritis occurs in a minority of patients.

Since 2014, the U.S. CDC has reported chikungunya virus disease cases among U.S. travelers returning from affected countries in the Americas, and local transmission was identified in Florida, Puerto Rico, and the U.S. Virgin Islands, According to the U.S. CDC, Chikungunya outbreaks have occurred in North and South America, Africa, Asia, Europe, and the Indian and Pacific Oceans and can be found in over 70 countries. An updated map is posted at this CDC link. Various countries worldwide have confirmed chikungunya virus outbreaks in 2023.


The CHIKV-VLP vaccine candidate is administered as a 40 µg dose muscular injection in clinical trials. 

CHIKV-VLP Side Effects

The most common solicited adverse event in a phase 2 study was pain at the injection site, reported in 12 (23%) of 53 participants who received the unadjuvanted vaccine (group 1) and 111 (31%) of 356 who received the adjuvanted vaccine. No vaccine-related serious adverse events were reported.

CHIKV-VLP News 2023

November 14, 2022 - Chris Cabell, M.D., chief medical officer and SVP clinical development at Emergent BioSolutions, stated in a press release, "We look forward to combining our product development expertise with the capabilities of the Armed Forces Research Institute of Medical Sciences in chikungunya epidemiology and field studies, and of our academic partners in infectious disease modeling and efficacy trial design, to find ways to address chikungunya disease, a public health threat for which no vaccine or treatment exists."

November 1, 2022 - Emergent BioSolutions Inc. announced results from a Phase 2 study evaluating the safety and immunogenicity of the CHIKV VLP vaccine candidate in prior recipients of other investigational alphavirus vaccines. The study demonstrated that the CHIKV VLP vaccine candidate was well-tolerated and immunogenic in alphavirus vaccine-naïve participants and participants previously vaccinated against the Venezuelan equine encephalitis virus. 

July 27, 2022 - Vadodara, India, continues to fight Vector-borne diseases as they make their presence felt in the city. In most months this year, the number of confirmed cases of these diseases remained higher than last year.

June 21, 2022 - Emergent BioSolutions Inc. announced two-year persistence data from its phase 2 clinical study evaluating the safety and immunogenicity of the CHIKV VLP vaccine candidate were published in The Lancet Infectious Diseases. The vaccine was well-tolerated and induced a robust and durable serum-neutralizing antibody immune response against the Chikungunya virus for up to two years. 

May 12, 2022 - A cohort study examining the incidence of chikungunya virus infections among Kenyan children with a neurological disease was reported in PLOS Medicine. This study observed that CHIKV infections are relatively more common than cerebral malaria and bacterial meningitis among children hospitalized with neurological disease in coastal Kenya.

February 24, 2022 - Emergent BioSolutions Inc. reported Q4 2021 total revenues of $723M and Adjusted EBITDA of $348M resulting in F.Y. 2021 total revenues of $1,793M and Adjusted EBITDA of $518M, and pipeline progress is expected across the R&D portfolio with the ongoing advancement of the CHIKV VLP Phase 3 clinical trial.

October 15, 2021 -  Emergent BioSolutions Inc. announced the first participant dosed in its pivotal phase 3 study evaluating the safety and immunogenicity of the Company's investigational chikungunya virus (CHIKV) virus-like particle (VLP) vaccine candidate, CHIKV VLP, in a single dose. CHIKV VLP is the only VLP-based vaccine currently in clinical development for active immunization against chikungunya disease.

May 26, 2021 - Emergent BioSolutions Inc. announced two-year persistence data from its Phase 2 clinical study. Two years post-vaccination, SNA responses were 19 times higher than pre-vaccination titers following a single adjuvanted 40 µg dose of the CHIKV VLP vaccine, supporting the persistence of the immune response. All subjects in the single-dose regimen remained seropositive at their one-year and two-year visits. The vaccine candidate was well-tolerated, and no significant vaccine-related safety concerns were identified.

March 23, 2021 - GAVI reported, 'Deaths from chikungunya are about one in 1,000 and almost always related to existing health problems, or being a newborn or over 65 years. Although death is less common than in other mosquito-borne diseases, the chronic joint pain and other symptoms associated with chikungunya can persist for months or years.'

March 19, 2021 - The global chikungunya vaccine market is estimated to reach USD 1.98 billion by 2027.

February 18, 2021 - Emergent BioSolutions Inc. reported financial results for the quarter and year ended December 31, 2020. The Company also reaffirmed its full-year 2021 forecast.

September 30, 2020 - The U.S. CDC issued a Level 1 Travel Alert regarding chikungunya risks in many parts of Africa. There is currently an outbreak in Ethiopia. Travelers should protect themselves by preventing mosquito bites.

April 17, 2020 - The U.S. NIH announced, 'After analyzing the results, the researchers concluded that the vaccine was safe and well-tolerated. None of the volunteers experienced serious adverse effects related to the vaccine. In addition, the volunteers who received the vaccine developed an immune response to the chikungunya virus that remained strong for th weeks of the study.

January 13, 2020 - Emergent BioSolutions Inc. announced that it had received an agreement from the European Medicines Agency to pursue its proposed development plan for its chikungunya virus virus-like particle (CHIKV VLP) vaccine candidate. The Company has proposed conducting a safety and immunogenicity Phase 3 trial using Serum Neutralizing Antibodies as an immune correlate of protection to predict the vaccine candidate's clinical benefit.

November 22, 2019 -  Emergent BioSolutions announced updated results from the interim analysis of its Phase 2 clinical study evaluating its chikungunya virus-like particle (CHIKV VLP) vaccine candidate across a series of dosing regimens.

April 26, 2019 - Study published by PLOS: Vaccination with a chikungunya virus-like particle vaccine exacerbates disease in aged mice. Conclusions: Unadjuvanted CHIK VLP vaccination elicits immune responses that protect 100% of adult mice against CHIKV infection. However, an improved vaccine/adjuvant combination is still necessary to enhance the protective immunity against CHIKV in the aged.

April 16, 2019 Emergent BioSolutions announced results from the interim analysis of its Phase 2 clinical study evaluating the safety and immunogenicity.

August 25, 2014 - The U.S. NIH issued a press statement: "The candidate vaccine prompted a robust immunological response in recipients and was very well tolerated," Ledgerwood says. "Notably, the levels of neutralizing antibody produced in response to the experimental vaccine were comparable to those seen in 2 patients who had recovered from a chikungunya virus infection acquired elsewhere."

January 28, 2021 - A VLP vaccine for the epidemic Chikungunya virus protects non-human primates against infection.

CHIKV-VLP Clinical Trials

Emergent's CHIKV-VLP vaccine candidate, a single-dose, 40 μg injection of adjuvanted, is being investigated in phase 3 clinical trials ( identifiers NCT05072080 and NCT05349617).

And on November 14, 2022, the Company announced a planned post-approval multicenter Phase 3b clinical study will evaluate the vaccine candidate's efficacy in preventing CHIKV disease and assess the utility of a model-guided disease surveillance framework to optimize the execution of a field efficacy trial using CHIKV as a model emerging pathogen.

On Nov. 1, 2022, the Company reported a Phase 2 parallel-group, age- and gender-matched, open-label study evaluating the safety and immunogenicity of an adjuvanted CHIKV VLP vaccine candidate in prior recipients of experimental alphavirus vaccines in comparison to a cohort of alphavirus vaccine-naïve individuals, enrolled 60 healthy adults at two U.S. sites. The vaccine candidate was well-tolerated, with no notable difference in the incidence of adverse events between the groups. The majority of solicited adverse events were mild or moderate. The most common adverse event was local injection site pain. The seroconversion rate 21 days post-vaccination was 100% in both groups. A higher percentage of prior alphavirus vaccine candidate recipients had a four-fold rise on study day eight, tightening the alphavirus vaccine-naïve group.

The randomized, double-blind, parallel-group, phase 2 study was conducted at three U.S. sites with 445 participants. Eligible participants were healthy CHIKV-naïve adults aged 18–45 years. The primary endpoint was the geometric mean titer of the anti-CHIKV neutralizing antibody on day 57 (28 days after the last vaccination). Safety was also assessed.