A study is being conducted to evaluate the efficacy and safety of Longidaze for the prevention and treatment of post-inflammatory pulmonary fibrosis and interstitial lung disease following COVID-19.

The aim of the study is to compare the outcomes associated with postinflammatory pulmonary fibrosis and interstitial lung disease among a cohort of adult patients after complicated pulmonary manifestations of COVID-19 in two groups: in a group of patients who were prescribed Longidaze® for treatment or prevention as part of routine clinical practice, and in the group of patients who underwent dynamic observation.

Inclusion Criteria:

1. Patients with residual lung changes after complicated COVID-19
2. Residual changes were detected no later than 2 months after the discharge after disease
3. Treatment of COVID-19 was in accordance with the standard of the then current temporary guidelines for the treatment of COVID-19
4. Age of patients over 18 years old
5. Negative polymerase chain reaction (PCR) test COVID-19 at least 2 times in respiratory samples or based on serology results in blood samples
6. Patients in the framework of routine clinical practice, in accordance with the instructions for use before inclusion in the study, were prescribed intramuscular treatment with Longidaze® at a dose of 3000 IU, 1 injection every 5 days for a total course of 15 injections or dynamic observation without the use of active therapy
7. The patient did not participate in other drug clinical trials within 1 month prior to Visit 1.
8. The patient or patient's caregiver agrees to participate in the trial and sign an informed consent form
9. Patient understands and agrees to follow the planned procedures.
10. Women with fertile potential must agree to use at least one method of contraception before completing participation in the study.

Exclusion Criteria:

1. Women during pregnancy and lactation and women planning to become pregnant during the study period
2. Severe background diseases, such as severe heart failure (class IV heart function), severe liver and kidney disease, severe bronchial asthma, severe chronic obstructive pulmonary disease, bronchiectasis, bullous emphysema and previously identified interstitial lung diseases, neurological diseases, tumors.
3. Long-term bed rest, regardless of its cause
4. Increased individual sensitivity to the components of the studied drug
5. Pathological conditions that determine the impossibility of patient participation in the study (by the decision of the investigator)
6. Medical history that, according to the investigator, does not allow the patient to be included in the study
7. A burdened allergic anamnesis, which, according to the investigator, does not allow the patient to be included in the study

Patients (over 18 years old) with residual changes in the lungs against the background of the transferred COVID-19, who were prescribed Longidaze®, lyophilisate for solution for injection, 3000 IU or underwent dynamic observation without the use of active therapy