In January 2024 Curevo Vaccine announced positive data from a Phase II trial of amezosvatein (also known as CRV-101) in comparison with Shingrix in participants aged 50 years and above. The vaccine is a non-mRNA, adjuvanted subunit vaccine that met “all primary endpoints” in the randomised, controlled, observer-blind trial.
Amezosvatein
Amezosvatein is the assigned, non-proprietary name for CRV-101, a vaccine that uses a subunit protein antigen called glycoprotein ‘E’ (gE). This is like GSK’s Shingrix, and also uses an adjuvant targeting the TLR4 pathway to boost the immune response to the gE antigen. Targeting this antigen is “proven to elicit a long-term, protective immune response to prevent shingles”.
“Amezosvatein was engineered to have a best-in-class safety profile in addition to manufacturing advantages to improve vaccine accessibility.”
The Phase II trial enrolled 876 participants across over a dozen US sites to receive either amezosvatein or Shingrix on an identical schedule of two doses, two months apart. Amezosvatein achieved both primary endpoints in the trial: Day 84 safety/tolerability, and Day 84 humoral immune response, the latter measured by the geometric mean concentration of anti-gE antibodies to both vaccines. Furthermore, it exhibited “lower rates” of solicited local and systemic adverse events. Thus, Curevo intends to advance the vaccine into global Phase III trials in 2024 to address the shingles vaccination market, which currently exceeds $4 billion.
Coverage concerns
Dr Guy De La Rosa is Curevo’s Chief Medical Officer and commented on the “disappointingly low” coverage rates despite Shingrix’s availability.
“A growing body of evidence suggests tolerability issues contribute to both vaccine hesitancy and avoidance of the required second dose.”
In response to this, amezosvatein was developed “specifically to provide high vaccine effectiveness” and tolerability.
“We are very excited by these Phase II data.”
George Simeon, Curevo’s CEO, noted that “fewer than 5% of eligible adults” in “most European countries and China” have received the necessary two doses of Shingrix. Furthermore, two thirds of US adults “still need to be immunised”.
“The market opportunity in shingles is large and underserved.”
Dr William Smith of the Alliance for Multispeciality Research, the primary investigator on the trial, identified a “clear unmet medical need” for a shingles vaccine with “improved tolerability and better accessibility”.
“If these data are confirmed in a Phase III trial, amezosvatein holds great promise in meeting the goal of broadening effective vaccination rates against shingles, a serious medical condition capable of causing significant, long-term disruption in adult populations.”
Could this development unseat GSK’s domination of the shingles market? We’re looking forward to exploring adult immunisation strategies in greater detail at the Congress in Washington this year; do join us there! If you can’t make it, why not subscribe to our newsletters?
There is a need for Shingles vaccines for under 50s, especially for those on new classes of immunotherapy modulators such as JAK inhibitors for rheumatoid arthritis etc. It would be great if trial extensions for younger adults were done in Phase 3?