Inclusion Criteria:  Age above 18 years Diagnosed to have COVID-19 by means of a real-time reverse transcription polymerase chain reaction (rRT-PCR) test performed on a respiratory (upper or lower respiratory) sample or positive IgM antibody test or a rapid antigen test with consistent clinicoradiologic findings within the previous 4 months Persistent respiratory symptoms Having post-COVID parenchymal involvement >10% of the lung parenchyma on visual inspection of the scans with the presence of radiologic signs of fibrosis (traction bronchiectasis/traction bronchiolectasis or honeycombing or reduced lung volumes), or having persistent reticulation or persistent consolidation despite a trial of glucocorticoids (minimum prednisolone dose of 10 mg/day, or equivalent) for a minimum period of 4 weeks after discharge for the acute COVID-19 illness  Exclusion Criteria:  Pregnant or lactating women Having absolute contraindication for pirfenidone or nintedanib (advanced liver cirrhosis, persistent elevation of liver transaminases, documented hypersensitivity to pirfenidone or nintedanib, receiving anticoagulants or high dose aspirin or having a vascular stent in situ) Known patient with diffuse lung disease prior to the diagnosis of COVID