The live-attenuated vaccine known as sCPD9 offers better control over SARS-CoV-2 than other vaccines due to its ability to replicate and amplify itself within the body's cells. This characteristic triggers various components of the immune system, leading to optimal and well-orchestrated responses. However, the replication capability of sCPD9 raises concerns about unintended transmission within the population.
To address this worry, scientists targeted a specific part of the spike protein known as the furin cleavage site. Removing this section effectively prevented the vaccine virus from spreading between cohabiting hamsters. Importantly, this modification didn't impact any other attributes of the sCPD9 vaccine candidate. In fact, it improved the vaccine's safety profile, even in animals with weakened immune systems.