NDV-HXP-S (known as ButanVac[2][3] or ADAPTCOV[4] in Brazil, COVIVAC[5] in Vietnam, HXP-GPOVac[6] in Thailand, Patria[7] in Mexico) is a COVID-19 vaccine candidate developed by a team led by Jason McLellan at the University of Texas at Austin,[8] together with groups from the Icahn School of Medicine at Mount Sinai and the National Institute of Allergy and Infectious Diseases Vaccine Research Center, based on an improved spike protein central to its resilience and efficacy.[9]

Butanvac embalagem.jpg
Packaging for the Brazilian version of NDV-HXP-S, ButanVac
Vaccine description
Vaccine typeviral vector or inactivated
Clinical data
Trade namesButanVac (Brazil)
COVIVAC (Vietnam)
HXP-GPOVac (Thailand)
Patria (Mexico)
Other namesADAPTCOV
Routes of
Intramuscular,[1] Intranasal

The name NDV-HXP-S comes from the terms Newcastle disease virus, HexaPro, and spike protein.[10][failed verification]


NDV-HXP-S uses the Newcastle disease virus as its viral vector or inactivated.[11]


Unlike vaccines such as Moderna's mRNA-1273, the Janssen vaccine, and Pfizer–BioNTech's tozinameran, which all require both specialized manufacturing facilities and also rare or expensive ingredients, NDV-HXP-S can be produced using chicken eggs in a fashion similar to flu vaccine production, making it especially important to and for middle- and low-income countries.[9] Those existing vaccines are based on the 2P spike, while NDV-HXP-S is further refined via the same process, resulting in a new spike called HexaPro;[12] the 2P spike contained two prolines compared with HexaPro's six. It is also more resistant to heat and chemicals than the original 2P spike; the vaccine can be stored at 2–8 °C.[10]



Its development was coordinated by the PATH Center for Vaccine Innovation and Access, and UT Austin and ISMMS have arranged royalty-free licensing agreements with labs and corporations in 80 countries. McLellan has noted that "the share of vaccines ['low- and middle-income countries' have] received so far is terrible".[9]

Clinical trialsEdit

São Paulo governor João Doria displaying Butanvac at a press conference on March 26, 2021.

As of April 2021 NDV-HXP-S is undergoing initial clinical trials in humans in at least four countries. In Brazil, on March 26, 2021, the Butantan Institute announced it would seek to begin clinical trials. Mexico-based Avimex plans to create an intranasal spray version of the vaccine. In Thailand the Government Pharmaceutical Organization is conducting a trial in coordination with Mahidol University.[13][14] Reflecting the freedom offered by the ease of the manufacturing process, Thai health minister Anutin Charnvirakul referred to the vaccine as "produced by Thai people for Thai people".[9]


  1. ^ "Study of a Live rNDV Based Vaccine Against COVID-19". ClinicalTrials.gov. United States National Library of Medicine. 4 May 2021. NCT04871737. Retrieved 4 May 2021.
  2. ^ "Butantan vai desenvolver e produzir nova vacina contra a Covid-19; testes clínicos da ButanVac devem começar em abril".
  3. ^ Simões E, Fonseca P (26 March 2021). "Brazil posts record 3,650 new COVID-19 deaths, unveils two homegrown vaccines". Reuters. Retrieved 7 April 2021. Earlier, Sao Paulo's Butantan biomedical institute said it will seek approval ... Butantan aims to produce 40 million doses of the Butanvac vaccine ... The vaccine was developed using a modified virus, which causes the Newcastle disease in birds ...
  4. ^ "Clinical Trial of the COVID-19 Vaccine (Recombinant, Inactivated) in Brazil (ADAPTCOV)". clinicaltrials.gov. United States National Library of Medicine. 6 August 2021. Retrieved 6 August 2021.
  5. ^ "A Phase 1/2 Safety and Immunogenicity Trial of COVID-19 Vaccine COVIVAC". clinicaltrials.gov. United States National Library of Medicine. April 2021. Retrieved 9 April 2021.
  6. ^ "Mahidol-GPO's human trials of its COVID-19 vaccine show promising results". Thai PBS World. 1 July 2021. Retrieved 19 July 2021.
  7. ^ Juarez, Carlos (22 April 2021). "Vacuna Patria: esto es lo que se sabe de su avance y eventual producción". The Logistics World. Retrieved 24 June 2021.
  8. ^ Cross R (20 July 2020). "What will it take to make an effective vaccine for COVID-19?". Chemical & Engineering News. 98 (28): 35–42. doi:10.1021/cen-09828-cover.
  9. ^ a b c d Zimmer C (5 April 2021). "Researchers Are Hatching a Low-Cost Coronavirus Vaccine". The New York Times. Retrieved 7 April 2021.
  10. ^ a b Airhart M (5 April 2021). "Human Trials Begin for a Low-Cost COVID-19 Vaccine to Extend Global Access". University of Texas. Retrieved 7 April 2021.
  11. ^ Sun W, Leist SR, McCroskery S, Liu Y, Slamanig S, Oliva J, et al. (2020). "Newcastle disease virus (NDV) expressing the spike protein of SARS-CoV-2 as vaccine candidate". EBioMedicine. 62: 103132. doi:10.1016/j.ebiom.2020.103132. PMC 7679520. PMID 33232870.
  12. ^ Hsieh CL, Goldsmith JA, Schaub JM, DiVenere AM, Kuo HC, Javanmardi K, et al. (September 2020). "Structure-based design of prefusion-stabilized SARS-CoV-2 spikes". Science. 369 (6510): 1501–1505. Bibcode:2020Sci...369.1501H. doi:10.1126/science.abd0826. PMC 7402631. PMID 32703906.
  13. ^ Clinical trial number NCT04764422 for "Assess the Safety and Immunogenicity of NDV-HXP-S Vaccine in Thailand" at ClinicalTrials.gov
  14. ^ Wipatayotin A (11 February 2021). "Thai-made vaccine ready 'by next year'". Bangkok Post. Bangkok Post Public Company Limited. Retrieved 9 April 2021.