At present there is no curative treatment for post-acute COVID-19 syndrome (PACS). Treatment is focused on symptom management and individualized rehabilitation. There is data indicating SARS-CoV-2 viral persistence and chronic immune system activation in PACS. We are proposing an interventional, randomized and placebo-controlled clinical intervention trial of nirmatrelvir/ritonavir (300/100 mg) or placebo/ritonavir (100mg), twice daily for 15 days, in patients suffering from severe PACS. Patients meeting the WHO definition of severe PACS will be identified from a database of 988 patients cared for by the Karolinska University Hospital Post-COVID clinics since May 2020, and in whom extensive clinical and laboratory examinations have been performed. A total of 400 patients will be enrolled in this study and these will be randomized in a 2:1 ratio to receive either nirmatrelvir/ritonavir or placebo/ritonavir. The study will include deep exploratory systems-level analyses of the immune system in PACS patients, including changes induced by nirmatrelvir/ritonavir (Paxlovid®) treatment. The purpose of this study is to evaluate the efficacy of nirmatrelvir/ritonavir for its potential ability to provide sustained improvement in quality of life, in non-hospitalized patients with post-COVID, a patient group with high unmet medical needs.~Hypothesis: Nirmatrelvir/ritonavir (Paxlovid®) improves health-related quality of life measured using the EQ-5D-5L VAS scale, as compared to placebo/ritonavir, in objective and pre-defined clinical phenotypes: postural orthostatic tachycardia syndrome (POTS), microvascular dysfunction, inappropriate sinus tachycardia, persistent fever, post exertional malaise (PEM), fatigue, brain fog, dyspnea, dysfunctional breathing patterns or inflammatory phenotypes (increased plasma D-dimer, CRP, ESR and ferritin).
The purpose of this study is to investigate the efficacy of orally administered nirmatrelvir/ritonavir compared with placebo/ritonavir to improve quality of life in non-hospitalized adult participants suffering from post-acute COVID-19 syndrome.