This is prospective observational study of long-term pathogenic treatment of Elizaria® in patients with paroxysmal nocturnal hemoglobinuria.

Paroxysmal nocturnal hemoglobinuria (PNH) is an ultra-rare, acquired, life-threatening, progressive clonal blood disease that is developed as a result of the expansion of one or more clones of hematopoietic stem cells with a somatic PIG A gene mutation. The main pathogenic mechanism of PNH development is a dysregulation of the complement system, in which there are no complement inhibitors CD55 and CD59 that are bounded by the GPI-anchor on the surface of blood cells, or there is a deficiency of them.

Eculizumab is the first drug for the pathogenetic therapy of PNH, a recombinant humanized monoclonal antibody against the C5 component of complement. Binding with high affinity to C5, eculizumab prevents the cleavage of C5 into C5a and C5b, thereby inhibiting the formation of pro-inflammatory cytokines (via C5a) and Membrane attack complex (MAC) (via C5b).

Using of eculizumab in patients with PNH leads to a significant decrease in hemolysis, the incidence of thrombosis and increasing of the quality of life of patients. It increases life expectancy with long-term using of eculizumab.

The drug Eculizumab, developed by JSC "GENERIUM", Russia, is a biological analogue (biosimilar) of the original drug Soliris®.

The population of the study is the patients with an established diagnosis of PNH who have indications for pathogenic treatment and are receiving Elizaria®.

The study duration for each patient will be at least 54 weeks for previously treated patients, and 58 weeks for previously untreated patients, including the Screening period and the observation period.

The study will include the Screening Period and the Observation Period:

• Screening Period - 2 weeks (Days 1 - 14);
• Follow-up is 52 weeks for previously treated patients and 56 weeks for previously untreated patients.

The screening period can be extended until the results of laboratory and instrumental studies are obtained, but no more than 14 days.

During the observation period, for the purpose of routine examination, it is planned to conduct a number of intermediate visits, approximately every 8 weeks (an acceptable interval of 6-10 weeks) between the Screening Visit (Visit 1) and the Study End Visit (Visit 13) in accordance with the plan of the dispensary observation of the patient. Additional visits and examinations may be carried out by the decision of the research physician.

If the patient is previously untreated, the patient undergoes induction therapy with Elizaria® at a dose of 600 mg weekly for 4 weeks with a further transition to maintenance therapy at a dose of 900 mg from the 5th week and then every 2 weeks.

Inclusion Criteria:

1. Male and female patients aged 2 years with an established diagnosis of PNH;
2. Prescribing Elizaria® as a pathogenetic therapy;
3. Signing by the patient of the informed consent form for participation in the study.

Exclusion Criteria:

1. Intolerance to eculizumab or other components of the drug.

The population of the study is the patients with an established diagnosis of PNH who have indications for pathogenic treatment and are receiving Elizaria®.