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News: J&J booster effective in original Pfizer recipients

The last few months have seen a rise in CDC-recommended booster-shots for many people, and since October a small study in Boston has tested whether mixing and matching booster shots would remain effective and safe.


The study, conducted at the Beth Israel Deaconess Medical Center, has just released results revealing that fully vaccinated adults who originally received the Pfizer vaccine are able to get the same effectiveness from a booster shot of Johnsson and Johnsson’s vaccine.


65 people were involved, 24 of which received a third Pfizer shot as their booster while the rest tested out the J&J booster. Both groups saw an increase in Covid-fighting T-cells, which are key to your immune system’s long-term defense against infection and serious disease onset in the event you are infected. Interestingly, the J&J vaccine booster shot demonstrated a T-cell increase that was almost double that of the Pfizer group.


The study also measured antibodies, which unlike T-cells, provide more short-term defense against the disease. The J&J booster group again saw a greater jump in antibodies than the Pfizer group, with more than double the antibody count in J&J between the second and fourth weeks. The difference in responses is still considered relatively small in antibodies. It should be noted that both groups still reached antibody and T-cell levels that are well above what scientists currently believe is needed for “strong protection.”


Importantly, the research was funded in part by Johnson & Johnson and the results have not yet been published publicly.


The research also contrasts with previous mix-and-match studies such as the work by the National Institutes of Health in October which reported significant antibody rise across Pfizer, J&J, and Moderna booster shots. In this study, J&J’s shot provided a smaller antibody response than the others. T-cell levels have not yet been published by the NIH.



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In addition to keeping you up to date on all things clinical trials, we also act as a digital CRO with a specific focus on patient recruitment and retention. We believe that patient recruitment and study startup (especially study design and study material) are heavily intertwined. After all, study design can make or break clinical trials, and the patient perspective should be considered when designing studies to ensure that patient targets are met not only on time but also on budget.


For Citruslabs, patient recruitment starts with study design and ends with trial completion. We recruit patients through our network of health apps, which enables you to connect with thousands of patients in real-time. The best part: these patients are already educated and prepared for the clinical trial process.


If you’d like to hear more about what we do, go here to read about what sets us apart, or here to read what our patients have to say about us.


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