The Shingrix vaccine for shingles is so much more effective primarily due to the adjuvant, Quillaja saponaria (QS). It looks like QS is particularly effective at boosting the immune response, which has positive implications for a host of diseases, not just shingles.
"In addition to weakened muscles, graying hair, and thinning skin, the human immune system also gets weaker and more vulnerable with age. That makes shingles especially painful and terrible for the elderly. The trademark rash, which usually resolves in about two weeks, isn’t even the worst symptom of shingles. About 90% of the time, the rash is preceded by a sharp, unrelenting, burning pain. Sometimes the pain lasts well after the rash has disappeared, for weeks and even months. This particular type of pain is called post-herpetic neuralgia, or PHN. Between 15% and 20% of people with shingles suffer PHN. Along with corneal abrasions, lower back pain, kidney stones, and labor and delivery, PHN is ranked the worst pains in medicine—so bad that it can lead to suicide.
...
Shingrix’s protection rates are unprecedented in the world of immunizations—especially among the elderly. For those 50 to 59 years of age, 96.8% are protected; for those 60 to 69 years of age, it’s 97.4%, for those older than 70 to 79 years of age, it’s 97.9%; and for those older than 80 years of age, it’s 97.6%. From a medical perspective, it’s hard to find a medical product that works this well in people this age.
...
So why was Shingrix better than Zostavax? The answer lies in an adjuvant that has never been used in the United States until now.
It’s called QS-21. The “QS” stands for Quillaja saponaria. Otherwise known as the soap bark tree, Quillaja saponaria is native to the country of Chile. Using a highly purified product derived from the tree’s bark (the 21st chromatographic peak in the purification process), researchers have now been able to do something that had once been considered impossible; dramatically boost a senescent (and therefore less robust) immune system. QS-21 is currently being studied for its capacity to enhance immune responses against influenza, malaria, hepatitis B virus, human papillomavirus, HIV, and tuberculosis vaccines as well as immunological strategies against lung cancer and malignant melanoma (10.4172/2329-6836.1000e113).
With the licensure of QS-21, an important door has been opened. For older adults, who are often the most vulnerable to severe and occasionally fatal infections, this kind of immune-boosting strategy will be a godsend.
The stats speak for themselves. Shingrix is phenomenal in its ability to protect against PHN. For those 50 to 59 years of age, 91.2% are protected; for those 60 to 69 years of age, it’s 89.4%; for those 70 to 79 years of age, it’s 93%; and for those older than 80, the rate is an impressive 71.2%. Protection afforded by Shingrix also lasts longer. Overall protection against shingles rash was 97.6% after one year, 92% after 2 years, 87.9% after 3 years, and 84.7% after 4 years"
https://www.thedailybeast.com/the-latest-shingles-vaccine-could-make-immune-responses-better-with-age
"In addition to weakened muscles, graying hair, and thinning skin, the human immune system also gets weaker and more vulnerable with age. That makes shingles especially painful and terrible for the elderly. The trademark rash, which usually resolves in about two weeks, isn’t even the worst symptom of shingles. About 90% of the time, the rash is preceded by a sharp, unrelenting, burning pain. Sometimes the pain lasts well after the rash has disappeared, for weeks and even months. This particular type of pain is called post-herpetic neuralgia, or PHN. Between 15% and 20% of people with shingles suffer PHN. Along with corneal abrasions, lower back pain, kidney stones, and labor and delivery, PHN is ranked the worst pains in medicine—so bad that it can lead to suicide.
...
Shingrix’s protection rates are unprecedented in the world of immunizations—especially among the elderly. For those 50 to 59 years of age, 96.8% are protected; for those 60 to 69 years of age, it’s 97.4%, for those older than 70 to 79 years of age, it’s 97.9%; and for those older than 80 years of age, it’s 97.6%. From a medical perspective, it’s hard to find a medical product that works this well in people this age.
...
So why was Shingrix better than Zostavax? The answer lies in an adjuvant that has never been used in the United States until now.
It’s called QS-21. The “QS” stands for Quillaja saponaria. Otherwise known as the soap bark tree, Quillaja saponaria is native to the country of Chile. Using a highly purified product derived from the tree’s bark (the 21st chromatographic peak in the purification process), researchers have now been able to do something that had once been considered impossible; dramatically boost a senescent (and therefore less robust) immune system. QS-21 is currently being studied for its capacity to enhance immune responses against influenza, malaria, hepatitis B virus, human papillomavirus, HIV, and tuberculosis vaccines as well as immunological strategies against lung cancer and malignant melanoma (10.4172/2329-6836.1000e113).
With the licensure of QS-21, an important door has been opened. For older adults, who are often the most vulnerable to severe and occasionally fatal infections, this kind of immune-boosting strategy will be a godsend.
The stats speak for themselves. Shingrix is phenomenal in its ability to protect against PHN. For those 50 to 59 years of age, 91.2% are protected; for those 60 to 69 years of age, it’s 89.4%; for those 70 to 79 years of age, it’s 93%; and for those older than 80, the rate is an impressive 71.2%. Protection afforded by Shingrix also lasts longer. Overall protection against shingles rash was 97.6% after one year, 92% after 2 years, 87.9% after 3 years, and 84.7% after 4 years"
https://www.thedailybeast.com/the-latest-shingles-vaccine-could-make-immune-responses-better-with-age