Abstract
Background
Bacille Calmette–Guérin (BCG) vaccination can potentially reduce the rate of respiratory infections in vulnerable populations. This study evaluates the safety and efficacy of VPM1002 (a genetically modified BCG) as prophylaxis against severe respiratory tract infections including COVID-19 in an elderly population.
Methods
In this phase III, randomized, double-blind, placebo-controlled, multicenter clinical trial, healthy elderly volunteers (n = 2064) were enrolled, randomized (1:1) to receive either VPM1002 or placebo, and followed up remotely for 240 days. The primary outcome was the mean number of days with severe respiratory infections at hospital and/or at home. Secondary endpoints included the incidence of self-reported fever, number of hospital and ICU admissions, and number of adverse events.
Results
A total of 31 participants in the VPM1002 group reported at least 1 day with severe respiratory disease and a mean number of days with severe respiratory disease of 9.39 ± 9.28 days while in the placebo group, 38 participants reported a mean of 14.29 ± 16.25 days with severe respiratory disease. The incidence of self-reported fever was lower in the VPM1002 group (odds ratio: 0.46; 95% CI: 0.28 to 0.74; p-value: 0.001) and consistent trends to less hospitalization and ICU admissions due to COVID-19 were observed after VPM1002-vaccination. Local reactions typical for BCG were observed in the V PM1002-vaccinated group, which were mostly of mild intensity.
Conclusions
Vaccination with VPM1002 is well tolerated and seems to have a prophylactic effect against severe respiratory diseases in the elderly. (ClinicalTrials.gov: NCT04435379)