What makes this vaccine unique from the FDA Breakthrough Therapy designation?

On July 13, 2021, Affinivax and Astellas Pharma announced that their jointly developed innovative pneumococcal vaccine ASP3772 has achieved positive results in phase 2 clinical trials

Based on the positive results of this phase 2 trial, the US FDA has granted ASP3772 breakthrough therapy designation to prevent pneumonia and invasive diseases caused by the serotype of Streptococcus pneumoniae in adults 50 years and older

The main results of this phase 2 clinical trial are as follows:

It was observed that ASP3772 was well tolerated, and the injection site and systemic reactions were mild and self-limiting, similar to the results observed in the control 13-valent vaccine group

1) Common local reactions are tenderness and pain, which occur within the first 2-3 days after vaccination, and there is no significant difference from the 13-valent vaccine group

2) During the safety assessment period up to 180 days after vaccination, no serious adverse events related to vaccination or clinical related abnormalities (vital signs, ECG, laboratory parameters) were observed, and no potential immune-mediated adverse events were observed

At the three dose levels studied, ASP3772 showed a strong immune response to all 24 pneumococcal serotypes contained in the vaccine

1) Compared with the approved 13-valent active control vaccine, ASP3772 showed similar or higher immune responses to the 13 serotypes shared by ASP3772 and the 13-valent vaccine

2) At all ASP3772 dose levels, ASP3772 showed statistically higher immunity to serotypes 3, 4, 5, 6A, 7F, 9V and 18C compared with 13-valent vaccine or 23-valent active control vaccine Answer

3) At the highest dose level of ASP3772, it showed a statistically higher immune response to serotypes 5 and 19F

4) For the remaining 11 serotypes not included in the 13-valent vaccine, ASP3772 also showed a statistically good immune response

ASP3772 also showed a more than 2-fold increase in antibody response to the two conserved protein antigens contained in it

▲Affinivax's MAPS technology platform (picture source: Affinivax's official website)

Note: The original text has been deleted

Reference materials:

[1] Affinivax and Astellas Present Safety and Immunogenicity Data from Phase 2 Study of ASP3772, a Novel 24 valent MAPS™ Vaccine for Streptococcus pneumoniae.