Trial Progress During Challenging Times

Work Package 2 is performing a vaccination trial in people aged 65 years and older. The study aims to compare the immune responses induced by two vaccines and helps to understand underlying mechanisms of non-responsiveness in different age groups. Due to COVID-19 restrictions the team had to temporarily pause the vaccination trial in spring 2020. At that time the team had only been able to vaccinate 40 participants.

In July 2020 the government relieved some restrictions on the COVID-19 regulations. This action enabled the team to restart the clinical trial, as now it was allowed to visit the older adults. The team reinitiated the vaccinations of the pneumococcal conjugate vaccine (PCV13). The visits for the remaining 286 was planned and the team finished the last visit on November 5th. In the figures below the number of participants and the division over de age groups for both the influenza (left) and the PCV13 vaccination (right) are shown.

As the PCV13 vaccination time point was at the same time point as the 6 month (M6) follow-up of the influenza vaccination, the team also prepared an amendment for the Ethical committee that allowed the team to request additional information at this time. After the approval was received, the team requested an additional blood sample by finger prick and additional questions with respect to COVID19 infections. These requests and finger prick sets were send out by mail early July. The additional requested information enable the team to obtain important serology data. A total of 225 participants submitted a finger prick sample. The obtained samples will be tested for flu specific antibodies using HI assays.

At the end of July, a shipment was done with serum samples from the first sample taken at flu vaccination (M0) and 1st month (M1) follow-up after vaccination, as well as the M6 time point from the 40 initial PCV13 vaccinated participants and their finger prick sample. This will allow identification of the flu responder profile and facilitate downstream analyses. In addition it will allow comparison of this test in a serum sample from vena puncture versus the finger prick sample. Data were shared beginning of November and the team is in the process of analyzing these data.