This is arguably the most seminal publication from the Brown group of 2023, published in the esteemed American Journal of Respiratory and Critical Care Medicine.
“A Randomized Controlled Clinical Trial of Nasal Immunization with Live Virulence Attenuated Streptococcus pneumoniae Strains Using Human Infection Challenge”
The article addresses the persistent global health issue of pneumococcal pneumonia, a type of lung infection caused by Streptococcus pneumoniae.
The researchers conducted a randomized controlled clinical trial using a controlled human infection model. Healthy adults were administered nasal doses of saline, wild-type Spn6B, or two genetically modified Spn6B strains (SpnA1 and SpnA3). After six months, participants were challenged with wild-type Spn to assess protection against the homologous serotype.
No serious adverse events were reported among the 125 participants who completed both study stages. Colonization rates were comparable in Stage I. Higher serum IgG responses (antibody levels and activity) were observed in the wild-type and SpnA1 groups compared to the SpnA3 group. Participants exposed to wild-type or SpnA1 in Stage I demonstrated partial protection against homologous challenge in Stage II, with lower recolonization rates compared to those exposed to SpnA3.
The study concludes that nasal colonization with genetically modified live attenuated Spn is safe. It suggests that this approach provides protection against recolonization, indicating the potential effectiveness of this strategy in preventing pneumococcal infections.
Significance of the research:
This research is crucial because it represents the first time a genetically engineered pneumococcus has been administered to a human.
The findings suggest that nasal administration of genetically modified live attenuated Spn could be developed into a vaccine for preventing pneumonia.
The potential development of a vaccine could have significant implications for addressing the global health burden associated with pneumococcal infections, particularly pneumonia.
In summary, this study represents a ground breaking step in exploring a novel approach to prevent pneumococcal infections, and its findings open the door to further research and potential vaccine development for pneumococcal pneumonia.
Published in AJRCCM August 2023. Click here to read the full article.