Study purpose:

- evaluate clinical efficacy ands afety of Prospekta in the treatment of cognitive, behavioral and psychiatric disorders in patients with vascular dementia.

Study objectives:

• evaluate and compare changes in cognitive functions, in behavioral and in psychiatric dementia symptoms in Prospekta and Placebo groups after 24-weeks of treatment
• evaluate and compare the frequency, severity and causal relationship of adverse events (AEs) with the type of therapy in Prospekta and Placebo groups (including central nervous system AEs during therapy, their relationship with the study drug and other characteristics).

Design: double-blind placebo-controlled randomized parallel-group clinical trial. The study will enroll male and female patients aged 60-85 years inclusively diagnosed with vascular dementia verified at Visit 1 according to the criteria of The National Institute of Neurological Disorders and Stroke National Institute of Neurological Disorders and Stroke-Association Internationale pour la Recherche et l'Enseignement en Neurosciences - NINDS-AIREN. Severity of vascular dementia should be moderate or mild (10-24 points according to Mini-Mental State Examination - MMSE), without signs of depression (total Cornell Scale for Depression in Dementia (CSDD) score ≤10).

After signing patient information sheet (informed consent form) to participate in the study, at Visit 1 (from day -14 to day 1) complaints and medical history will be collected, objective examination, recording vital signs (BP, RR, HR) will be performed and compliance of the subject's diagnosis with NINDS-AIREN vascular dementia criteria will be evaluated. The study investigator will assess cognitive disorders using Mini-Mental State Examination (MMSE) and Montreal Сognitive Assessment (МоСА). The investigator and the patient's caregiver will fill Neuropsychiatric Inventory Сlinician (NPI-С), and СSDD scales. The patient will undergo brain MRI (in the absence of brain MRI data within the previous 12 months before inclusion in the study).

Concomitant therapy and concomitant diseases and conditions will be recorded. If inclusion/exclusion criteria are met, the patient will be randomized to one of the two groups: group 1 will receive Prospekta 2 tablets twice daily; group 2 will receive Placebo using the study drug dosing regimen.

Treatment duration will be 24 weeks during which 6 Visits will be made. At visits 2 and 3 (week 4±3 days and week 8±3 days) the study investigator will make a phone call and collect the complaints, monitor the prescribed and concomitant therapy, evaluate therapeutic safety.

At visit 4 (week 12±7 days) the study investigator will collect complaints, record objective examination findings and vital signs, monitor the prescribed and concomitant therapy, evaluate therapeutic safety and compliance, dispense the study drug until the next visit. The study investigator and caregiver will fill NPI-C.

At visits 5 and 6 (week 16±3 days and week 20±3 days) the study investigator will make a phone call and collect the complaints, monitor the prescribed and concomitant therapy, evaluate therapeutic safety.

At visit 7 (week 24±7 days) the study investigator will collect complaints, perform objective examination, record vital signs, monitor the prescribed and concomitant therapy, evaluate therapeutic safety, evaluate compliance. The study investigator will fill MоСА and Clinical Global Impression Efficacy Index (CGI-EI). The study investigator and caregiver will fill NPI-C.

During the study the treatment for concomitant diseases will be allowed with the exception of the drugs specified in the section "Prohibited concomitant therapy".

Inclusion Criteria:

1. Subjects aged 60-85 years old inclusively.

2. Subjects with verified diagnosis of vascular dementia.

3. Presence of all the vascular dementia criteria according to NINDS-AIREN:

   A. Presence of dementia, which is defined as a decline in cognitive function relative to the previous level of functioning, manifested by impairments in memory and two or more cognitive domains (orientation, attention, language, visuospatial functions, executive functions, motor control and praxis), preferably established during a clinical trial and confirmed by neuropsychological testing.

   The cognitive impairment must be so severe that it affects daily activity, reducing it independently of the physical consequences of the stroke.

   B. The presence of cerebrovascular disease, confirmed by signs of focal damage on neurological examination, such as hemiparesis, lower facial weakness, Babinski sign, sensory deficit, hemianopsia or dysarthria associated with stroke (either a history of stroke or absence of such anamnestic information), and neuroimaging (CT or MRI) signs of cerebrovascular disease, including multiple infarcts in the territory of large vessels, or a single infarction in a strategically important area (angular gyrus, thalamus, basal ganglia, or the territory of the anterior or posterior cerebral arteries), as well as multiple lacunae in the region of the basal ganglia or white matter, or significant damage to the periventricular white matter, or a combination of the above lesions.

   C. There is an association between dementia and cerebrovascular disease as follows:

   1. onset of dementia within 3 months of stroke;
   2. sharp deterioration of cognitive functions; or fluctuating, stepwise progression of cognitive impairment.

4. Availability of permanent caregiver throughout the study (nurse or relatives).

5. Total Mini-Mental State Examination (MMSE) score - 10-24.

6. Total MoCA score <26.

7. Total NPI-C aggression and agitation domain score ≥14.

8. Аbsence of depression (total Cornell Scale for Depression in Dementia (CSDD) score ≤10).

9. Brain MRI confirming the diagnosis of vascular dementia within 1 year prior to enrollment (or brain MRI performed at enrollment visit).

10. Patients giving their consent to use reliable contraception throughout the study (for males).

11. Availability of signed patient information sheet and informed consent form for participation in the clinical trial.

Exclusion Criteria:

1. Signs of intracerebral hemorrhage, brain tumours causing dementia.
2. Alzheimer's disease, Parkinson disease, Lewy body dementia, multiple system atrophy, Jacob-Creutzfeld disease, Pick syndrome, corticobasal degeneration.
3. Injuries of head (S00-S09) associated with impaired consciousness, cerebral contusion or open craniocerebral traumas.
4. Toxicity-related dementia (including drug-induced), multiorgan failure or metabolic and toxic disorders (chronic hypothyroidism, decompensated diabetes mellitus, avitaminoses, etc.).
5. Other psychiatric diseases besides dementia: mental disorders and behavioral disorders due to use of psychoactive substances (F10-19) schizophrenia, schizotypal and delusional disorders (F20-29).
6. Mental retardation (F70-79).
7. Inflammatory lesions of the brain with persistent neurological deficit.
8. Malignant neoplasms.
9. Previously diagnosed cardiovascular diseases with functional class IV (according to New York Heart Association, 1964).
10. Unstable angina pectoris, myocardial infarction or ischemic stroke within the last 6 months.
11. Female patients with childbearing potency.
12. Allergy/intolerance of any of the study drugs components including secondary to lactase deficiency.
13. Any conditions which, according to the investigator opinion, may interfere with the patient's participation in the study.
14. History of treatment noncompliance, mental diseases, alcoholism or drug abuse which will prevent from following the study procedures, according to investigator's opinion.
15. Participation in clinical trials for 3 months prior to enrollment in this study.
16. Use of any medications specified in "Prohibited concomitant medications" within 1 month before enrollment.
17. Patients who are related to any of the on-site research personnel directly involved in the conduct of the trial or are an immediate relative of the study investigator. 'Immediate relative' means husband, wife, parent, son, daughter, brother, or sister (regardless of whether they are natural or adopted).
18. Patients who work for OOO "NPF "Materia Medica Holding" (i.e. the company's employees, temporary contract workers, designated officials responsible for carrying out the research or any immediate relatives of the aforementioned).