Our Matrix-M™ adjuvant technology

Novavax vaccines incorporate our Matrix-M adjuvant.

What is our Matrix-M adjuvant?

Our Matrix-M adjuvant comes from saponins, naturally occurring compounds in the bark of the Quillaja saponaria (Soapbark) tree, commonly found in Chile. Saponins have a long history of being used for their medicinal properties.1 A vaccine containing another saponin‐based adjuvant has already been approved by the European Medicines Agency (EMA) and the US Food and Drug Administration (FDA).1,2

Quilliaja saponaria (Soapbark) tree. Bark containing saponins.

Novavax produces its Matrix-M adjuvant through a carefully designed process that results in very small, spherical particles that resemble a honeycomb-like structure when viewed through a high-power microscope. Matrix-M adjuvant particles are smaller than a human hair.

Our Matrix-M adjuvant is a key element of our technology platform. When mixed with our vaccine nanoparticles, this combination of ingredients has been shown to enhance the immune system response to our vaccines.6

How is Matrix-M made?

Soapbark trees are grown and harvested in very regulated, controlled conditions. When the trees are pruned, bark is harvested and ground into fine, pure powder. Saponins are extracted and prepared for use. Once all the processing steps are complete, the Matrix-M adjuvant is mixed with vaccine nanoparticles to produce the finished, ready-to-use vaccine.

Matrix-M adjuvant production process

Saponins, from the Quillaja saponaria tree, help generate a robust immune response.

Trees are pruned and the bark is harvested

Saponins are found in the tree’s bark. The bark is harvested sustainably, without felling the whole tree.

Quilliaja saponaria (Soapbark) tree. Bark containing saponins.
The bark is processed

The bark extract is processed into Fraction-A and Fraction-C, then freeze-dried (lyophilized). These powders contain “raw” saponin molecules.

Fraction-A. Fraction-C.
Liquid formulation prepared

Fraction-A and Fraction-C, as liquids, are formulated with phospholipids and cholesterol, producing the distinctive nanostructures of Matrix-A and Matrix-C adjuvants, respectively.

Phospholipid. Fraction-C. Franction-A. Cholesterol.
Matrix-M adjuvant formation

Matrix-A and Matrix-C adjuvant components are mixed to form Matrix-M adjuvant.

Matrix-C adjuvant. Matrix-A adjuvant.
Final vaccine

The Matrix-M adjuvant is mixed with the vaccine antigen to form the final vaccine product.

Vaccine nanoparticle

Infographic displaying the Matrix-M adjuvant production process

The harvesting practice of Quillaja is regulated within Chile, regardless of use.

Saponins are not only used in vaccines but also in the food industry and elsewhere.5

The pharmaceutical industry only uses a relatively small proportion of the total amount of saponins produced. These saponins, however, must be of extremely high quality and part of a sustainable supply.

Because of the high demand for this naturally occurring product, the harvesting of saponin-producing trees is highly regulated. Significant investments have been made in forestry and production practices to ensure a sustainable supply. Under Chilean law, landowners need a special permit to cut down a Quillaja saponaria Molina tree, and are only allowed to prune up to 35% of its biomass every 5 years.7 Specially designed, low-impact harvesting methods have been developed,7 and harvesting is coupled with reforestation efforts. Saponin extraction methods are also under constant review to improve efficiency and quality, and Novavax is committed to the responsible, sustainable harvesting of saponins for use in our vaccines.

  1. Pulendran B, et al. Nat Rev Drug Discov. 2021;20(6):454–475.
  2. FDA. Shingrix (Zoster Vaccine Recombinant, Adjuvanted) Prescribing Information. 2017.
  3. Bonam SR, et al. Trends Pharmacol Sci. 2017;38(9):771–793.
  4. Martins K, et al. The Lancet Discovery Science. 2016; 3: 67-78.
  5. Pulendran B, et al. Nature Reviews Drug Discovery. 2021; 20: 454–475.
  6. Keech C, et al. N Engl J Med. 2020;383(24):2320–2332.
  7. San Martín R, Briones R. Econ Bot. 1999;53:302–311.

A brief history of adjuvants in vaccine technology

An adjuvant is an ingredient in a vaccine that enhances the immune system’s response to that vaccine. Adjuvants help the immune system better recognize what’s in a vaccine and remember it longer, increasing the amount of time that a vaccine may offer protection. 4, 5

The first adjuvant was added to a vaccine over 100 years ago, improving the strength and duration of protection.1 Adjuvants are frequently used in protein-based vaccines.1, 3 Novavax has developed its own proprietary adjuvant technology, known as Matrix-M, designed to work with our nanoparticle vaccines.