QS-21
(Redirected from
QS21
)QS-21 is a purified
soap bark tree (Quillaja saponaria), which is native to the countries of Chile, Peru, and Bolivia.[1] The crude drug (Quillajae cortex) is imported from Peru and Chile.[2]
The extract contains
water-soluble triterpene glycosides, which are members of a family of plant-based compounds called saponins. It has been tested as an adjuvant in various vaccines in attempts to improve their efficacy. It is believed to enhance both humoral and cell-mediated immunity.[1]
Isolation of QS-21 destroys the soap bark tree, which has resulted in regulation of the tree by the governments where it is grown. A
acyl chain compositions.[3]
QS-21 has undergone clinical evaluation as an additive for various trial vaccines, including those for
.Agenus Inc. is the sole US-manufacturer of an FDA-approved, patented extract. Supplies are tightly controlled, and the US has invoked the US Defense Production Act to preserve vaccine raw materials for its own companies.[5][6]
See also
References
- ^ PMID 21506644.
- ^ Max Wichtl, ed. (2004). Herbal Drugs and Phytopharmaceuticals: A Handbook for Practice on a Scientific Basis. Medpharm Publishers. p. 492. ISBN 3-88763-100-5.
- PMID 22866694.
- ^ "SHINGRIX package insert" (PDF). Food and Drug Administration. Retrieved 7 April 2019.
- ^ VISWANATH, P. (April 29, 2021) "COVID-19: Raw material crunch pushes vaccine makers to look at indigenization". moneycontrol.com. Retrieved 30 April 2021.
- ^ Wang Pengfei (March 2021). "Natural and Synthetic Saponins as Vaccine Adjuvants" Vaccines 9(3):222. PMID: 33807582 PMCID: PMC8001307 DOI: 10.3390/vaccines9030222.