The objective of this study is to evaluate whether the administration by inhalation of ozone plasma favorably modifies lung function and inflammatory parameters in patients with pulmonary sequelae associated with coronavirus 19 infection (SARS-COV-2). We will conduct an open-ended, uncontrolled clinical trial in 35 male and female patients, between 25-80 years of age with previous confirmed diagnosis of COVID-19 infection with negative nasopharyngeal polymerase chain reaction assay (PCR) test and without active disease, patients will also continue with their usual treatment. Clinical findings and laboratory and cabinet tests include a basal and 14-day metabolic and inflammatory profile, body weight, body mass index (BMI) and blood pressure will be determined during the initial and final visit, as well as respiratory parameters by pulmonary function tests (spirometry, TLCo) and performing the 6 min walk test in endless band with pre- and post-walk oximetry measurements at the beginning and end of the study. Adverse events to treatment will be documented. Statistical analysis: Mann-Whitney U test and Wilcoxon exact test. A p \<0.05 shall be considered statistically significant.
