General dynamics of the URT microbiome and microbial signs of recovery in COVID-19 patients.

COVID-19 is caused by an airborne virus, SARS-CoV-2. The upper respiratory tract (URT) is, therefore, the first system to endure the attack. Inhabited by an assemblage of microbial communities, a healthy URT wards off the invasion. However, once invaded, it becomes destabilised, which could be crucial to the establishment and progression of the infection. We examined 696 URT samples collected from 285 COVID-19 patients at three time-points throughout their hospital stay and 100 URT samples from 100 healthy controls. We used 16S ribosomal RNA sequencing to evaluate the abundance of various bacterial taxa, α-diversity, and ß-diversity of the URT microbiome. Ordinary least squares regression was used to establish associations between the variables, with age, sex, and antibiotics as covariates. The URT microbiome in the COVID-19 patients was distinctively different from that of healthy controls. In COVID-19 patients, the abundance of 16 genera was significantly reduced. A total of 47 genera were specific to patients, whereas only 2 were unique to controls. The URT samples collected at admission differed more from the control than from the samples collected at later stages of treatment. The following four genera originally depleted in the patients grew significantly by the end of treatment: Fusobacterium, Haemophilus, Neisseria, and Stenotrophomonas. Our findings strongly suggest that SARS-CoV-2 caused significant changes in the URT microbiome, including the emergence of numerous atypical taxa. These findings may indicate increased instability of the URT microbiome in COVID-19 patients. In the course of the treatment, the microbial composition of the URT of COVID-19 patients tended toward that of controls. These microbial changes may be interpreted as markers of recovery.

[Clinical and economic analysis of Reslizumab use in the treatment of patients with severe allergic eosinophilic asthma].

Asthma is a heterogeneous chronic disease of airways. One of its endotypes is eosinophilic asthma, accompanied by both peripheral blood and airway eosinophilia, where severe eosinophilia is usually associated with more severe asthma. Anti - interleukin-5 (IL-5) monoclonal antibodies (MAb) can reduce eosinophil counts in peripheral blood and tissues in asthma patients. The first drug of this class registered in Russia was reslizumab. AIM: Comparative clinical and economic analysis of reslizumab use in patients with allergic asthma and eosinophilia. MATERIALS AND METHODS: Omalizumab was chosen as a reference drug, because until now it was the only MAb for the treatment of severe asthma in Russia. The study population included patients with allergic asthma with both high levels of IgE and high eosinophil counts in peripheral blood, i.e. individuals eligible for both omalizumab and reslizumab treatment. A decrease in the number of exacerbations requiring prescription of systemic corticosteroids and an increase in QALY index was used as efficacy criteria. An indirect comparative study was used, because no direct comparison has been conducted to date. As a result, reslizumab demonstrated a statistically significant reduction in the frequency of clinically significant asthma exacerbations compared with omalizumab. The utility of the both asthma treatment strategies was compared using Markov models, taking into account the frequency of exacerbations, their severity, as well as decrease in QALYs due to exacerbations. The time horizon was 12 months. RESULTS: Reslizumab treatment was 37.2% less expensive compared with omalizumab for the patients who are equally eligible for the both drugs. The calculated cost - effectiveness and cost - utility ratios were in favor of reslizumab. Budget impact analysis showed a significant effect of reslizumab on reducing budget costs. If reslizumab is used in 4250 patients (an estimated number of patients with severe allergic asthma and eosinophilia in Russia), this would reduce the costs for their treatment by up to 4896 million rubles per year. CONCLUSIONS: For patients with severe allergic eosinophilic asthma who are equally eligible for the both drugs, reslizumab can be considered a more reasonable medical technology in terms of pharmacoeconomics when compared with omalizumab.