A Phase 3 interventional study of Longidaza® and Placebo in Post-Acute COVID-19 Syndrome, Lung Disease With Polymyositis and Fibrosis, sponsored by NPO Petrovax. Completed at 30 sites in Russian Federation. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2025-06-03.
Sponsored by NPO Petrovax · Phase 3, Interventional, and Treatment
The goal of this clinical study is to evaluate the efficacy and safety of Longidaza®, lyophilisate for preparation of solution for injection, at a dose of 3000 IU compared to placebo in the treatment of adult patients with residual changes in the lungs after COVID-19 infection
The main objective of the clinical study was to prove the superiority of the efficacy of the drug Longidaza® over placebo when used in adult patients with residual changes in the lungs after COVID-19 infection based on the dynamics of respiratory function
604 studies on the registry are indexed under Post-Acute COVID-19 Syndrome; 201 are open to participants now.
This study's enrollment of 392 is above the median of 60 across 416 interventional studies indexed under Post-Acute COVID-19 Syndrome.
Browse Post-Acute COVID-19 Syndrome studies →NPO Petrovax is the lead sponsor of 14 studies on the registry; 2 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
COPD
Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bovhyaluronidase azoximer, 3000 IU
Drug: Longidaza®
The placebo will contain no active pharmaceutical ingredients.
Drug: Placebo
dose 3000 IU intramuscularly once every 5 days, 15 injections
Also known as: Bovhyaluronidase azoximer
intramuscularly once every 5 days, 15 injections
Change in Forced vital capacity (FVC) (visit 4)
Change in the FVC (%) compared with the initial data according to spirometry data after completion of the course of therapy
Time frame: Baseline to Day 71±1
Slowing the decline in respiratory function
Slowing the decline in respiratory function (FVC (%) compared with the initial data after the end of the observation period
Time frame: Baseline to Day 180±3
Change in FVC (visit 5)
Change in the FVC (%) compared with the initial data after the end of the observation period
Time frame: Baseline to Day 180±3
The proportion of patients with an increase in the FVC (%)
The proportion of patients with an increase in the FVC (%) by 10% or more compared to the initial values after Visit 4 and Visit 5
Time frame: Baseline, Day 71±1, Day 180±3
Dynamics of hemoglobin oxygen saturation (SpO2)
Dynamics of SpO2 values at rest after Visit 4 and Visit 5
Time frame: Baseline, Day 71±1, Day 180±3
The proportion of patients with SpO2 ≥ 93% and < 93%
The proportion of patients with SpO2 value at rest ≥ 93% and \< 93% after Visit 4 and Visit 5
Time frame: Baseline, Day 71±1, Day 180±3
The proportion of patients with desaturation
The proportion of patients with desaturation, defined as a decrease in SpO2 by ≥ 4% after 6-minute walk test (6MWT) after Visit 4 and Visit 5
Time frame: Baseline, Day 71±1, Day 180±3
The proportion of patients with an increase in the distance of 6MWT
The proportion of patients with an increase in the distance of 6MWT by 50 m or more after Visit 4 and Visit 5
Time frame: Baseline, Day 71±1, Day 180±3
The proportion of patients with a decrease in the severity of dyspnea on the Borg scale
The proportion of patients with a decrease in the severity of dyspnea on the Borg scale by ≥ 2 points after Visit 4 and Visit 5
Time frame: Baseline, Day 71±1, Day 180±3
The proportion of patients with a decrease in the severity of dyspnea on the Modified Medical Research Council Dyspnea Scale (mMRC)
The proportion of patients with a decrease in the severity of dyspnea on the mMRC by ≥ 1 point after Visit 4 and Visit 5
Time frame: Baseline, Day 71±1, Day 180±3
Change in cough severity on the Visual Analogue Scale (VAS)
Change in cough severity on the VAS after Visit 4 and Visit 5
Time frame: Baseline, Day 71±1, Day 180±3
Change in the assessment of the quality of life according to the European Quality of Life 5-Dimension 5-Level Questionnaire (EuroQol-5D-5L)
Change in the assessment of the quality of life according to the EuroQol-5D-5L after Visit 4 and Visit 5
Time frame: Baseline, Day 71±1, Day 180±3
Plan to share: No
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Ran from Apr 2022 to primary completion in Dec 2023, 20 months.
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This study is completed, as verified in May 2025. You cannot join it, but the record below documents what was studied.
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Post-Acute COVID-19 Syndrome →
NPO Petrovax