Article · Wikipedia archive · Last revised Jun 10, 2026

Matrix-M

Matrix-M is a vaccine adjuvant, a substance that is added to various vaccines to stimulate the immune response. It was patented in 2020 by Novavax and is composed of nanoparticles from saponins extracted from Quillaja saponaria (soapbark) trees, cholesterol, and phospholipids. It is an immune stimulating complex (ISCOM), which are nanospheres formed when saponin is mixed with two types of fats.

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Matrix-M is a vaccine adjuvant, a substance that is added to various vaccines to stimulate the immune response.123 It was patented in 2020 by Novavax4 and is composed of nanoparticles from saponins extracted from Quillaja saponaria (soapbark) trees, cholesterol, and phospholipids.567 It is an immune stimulating complex (ISCOM), which are nanospheres formed when saponin is mixed with two types of fats.8

Composition

Matrix-M contains a complex mix of saponins extracted from the bark of soapbark trees (Quillaia) packaged into nanoparticles made of cholesterol and phospholipids. 15% of the nanoparticles are known as Matrix-C and contain saponins derived from "Fraction C" of the tree bark extract (mainly QS-21). Matrix-C has strong adjuvant activity but is also highly reactogenic (lethargy and lethality in mice). The remaining 85% are known as Matrix-A and contain "Fraction A" saponins. Matrix-A is a weaker adjuvant but is also very well tolerated. Combined, they form a strong adjuvant with acceptable reactogenecity.9

Packaging saponins into nanoparticles achieves three things:9

  • Protection of the saponin molecule from hydrolysis
  • Protection of tissue from direct saponin irritation (raw QS-21 causes immediate pain at injection site and also hemolysis in vitro)
  • Targeted delivery of saponins to phagocytes

Forerunners to the Matrix-M technology include ISCOM (Morein et al., 1984) and ISCOMATRIX (CSL Limited, 2012).9

Use

Adjuvants increase the body's immune response to a vaccine by creating higher levels of antibodies.10 They can either enhance, modulate, and/or prolong the body's immune response, reducing the number of vaccinations needed for immunization.11

The Matrix-M adjuvant is used in a number of vaccine candidates, including the malaria vaccine R21/Matrix-M,112 influenza vaccines,2 and in the approved Novavax COVID-19 vaccine.513 In 2021, the R21/Matrix-M malaria vaccine candidate showed a 72% in sites with seasonal implementation and 67% in sites with age-based implementation in the modified per-protocol analysis. /> In influenza vaccine candidates, Matrix-M was shown to offer cross-protection against multiple strains of influenza.1323

Novavax is also testing a combined flu and COVID-19 vaccine candidate with Matrix-M.14

References

References

  1. Datoo, Mehreen S.; Natama, Magloire H.; Somé, Athanase; Traoré, Ousmane; Rouamba, Toussaint; Bellamy, Duncan; Yameogo, Prisca; Valia, Daniel; Tegneri, Moubarak; Ouedraogo, Florence; Soma, Rachidatou (2021-05-15). "Efficacy of a low-dose candidate malaria vaccine, R21 in adjuvant Matrix-M, with seasonal administration to children in Burkina Faso: a randomised controlled trial". The Lancet. 397 (10287): 1809–1818. doi:10.1016/S0140-6736(21)00943-0. ISSN 0140-6736. PMC 8121760. PMID 33964223.
  2. Magnusson, Sofia E.; Reimer, Jenny M.; Karlsson, Karin H.; Lilja, Lena; Bengtsson, Karin Lövgren; Stertman, Linda (2013-03-25). "Immune enhancing properties of the novel Matrix-M adjuvant leads to potentiated immune responses to an influenza vaccine in mice". Vaccine. 31 (13): 1725–1733. doi:10.1016/j.vaccine.2013.01.039. ISSN 0264-410X. PMID 23384754.
  3. "NanoFlu is on the FDA's Vaccine Fast-Track". www.precisionvaccinations.com. Archived from the original on 2021-10-27. Retrieved 2021-10-27.
  4. "US Patent for Highly efficient influenza matrix (M1) proteins Patent (Patent # 10,544,399 issued January 28, 2020) - Justia Patents Search". patents.justia.com. Retrieved 2022-07-21.
  5. Satyanarayana, Megha (2021-08-17). "A new, powerful malaria vaccine may be on the horizon". cen.acs.org. Retrieved 2021-10-27.
  6. "Is Old Vaccine Technology the Key to Hesitancy?". www.medpagetoday.com. 2021-06-17. Retrieved 2021-10-28.
  7. King, Anthony (2021-02-04). "Covid vaccination efforts bolstered by trial results from J&J and Novavax". Chemistry World. Retrieved 2021-10-28.
  8. Milicic, Anita (24 March 2021). "Adjuvants: the unsung heroes of vaccines". The Conversation. Retrieved 2021-10-28.
  9. Stertman, L; Palm, AE; Zarnegar, B; Carow, B; Lunderius Andersson, C; Magnusson, SE; Carnrot, C; Shinde, V; Smith, G; Glenn, G; Fries, L; Lövgren Bengtsson, K (31 December 2023). "The Matrix-M™ adjuvant: A critical component of vaccines for the 21(st) century". Human Vaccines & Immunotherapeutics. 19 (1) 2189885. doi:10.1080/21645515.2023.2189885. PMC 10158541. PMID 37113023.
  10. "Moths and tree bark: How the Novavax vaccine works". www.nebraskamed.com. Retrieved 2021-10-27.
  11. Bonam, Srinivasa Reddy; Partidos, Charalambos D.; Halmuthur, Sampath Kumar M.; Muller, Sylviane (September 2017). "An Overview of Novel Adjuvants Designed for Improving Vaccine Efficacy". Trends in Pharmacological Sciences. 38 (9): 771–793. doi:10.1016/j.tips.2017.06.002. ISSN 1873-3735. PMID 28668223. S2CID 205409092.
  12. "Malaria vaccine becomes first to achieve WHO-specified 75 percent efficacy goal". ScienceDaily. Retrieved 2021-10-27.
  13. Borrell, Brendan (2020-10-21). "The Tree That Could Help Stop the Pandemic". The Atlantic. Retrieved 2021-10-26.
  14. Tribble, Sarah Jane (2021-07-20). "Novavax's effort to vaccinate the world, from zero to not quite warp speed". Quartz. Retrieved 2023-04-13.