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Cerebrolycin for Treatment of Covid-related Anosmia and Ageusia

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT04830943
Recruitment Status : Completed
First Posted : April 5, 2021
Last Update Posted : April 5, 2021
Information provided by (Responsible Party):
Sherifa Ahmed Hamed, Assiut University

Brief Summary:
The loss of smell and taste is a prominent symptom of COVID-19. Studies found that patterns of smell loss due to Covid-19 infection differ from that of other respiratory viruses being much more profound in the Covid-19 patents and did not associate with runny, congested, or blocked-up nose. The researchers suggest that smell and taste testing can be used for fast COVID-19 screening. Studies found that the Covid-19 virus has similarities with severe acute respiratory syndrome coronavirus (SARS-CoV), which has been reported to enter the brain, via smell receptors in the nose. The sudden onset and relatively fast recovery in some patients suggest that COVID-19 anosmia is not caused by damage to the central nervous system but rather by the loss of smell information before it gets to the brain (smell receptors). They also found that it has different behavior from other respiratory viruses as it causes over-reaction of the immune system (or a cytokine storm). Trials to treat post-COVID anosmia using local steroid applications, sniffing of strong odors or scents or use of different vitamins (for several weeks to months) did not provide rapid, satisfactory or even significant recovery of olfactory dysfunction. Fortunately, the olfactory neurons can regenerate, however, studies reported variable prognoses, some patients recovered within weeks which others may have persistent deficits for months or even a year. In this study, the researchers hypothesize that cerebrolysin, a drug of neurotrophic and neuroprotective properties, can be used to treat patients with persistent post-COVID anosmia or ageusia or promote functional recovery of smell and taste deficits.

Condition or disease Intervention/treatment Phase
Covid19 Related Anosmia and Aguesia Drug: Cerebrolysin Phase 4

Detailed Description:
Initial descriptions of the COVID-19 pandemic have focused on its acute severe manifestations. After several months, data have emerged about the mild disease and Post-COVID syndrome. The diminished senses of smell (or hyposmia/anosmia) and taste (or hypogeusia/ageusia) have been commonly reported in the pandemic. Hyposmia/anosmia and hypogeusia/ageusia have also been reported with previous coronaviruses. In late March, the professional society of Ear, Nose, and Throat (ENT) in the United Kingdom (UK) published an advisory on evidence from South Korea, China, and Italy that significant number of COVID-19 positive patients also lost smell and/or taste. Based also on several other reports which reported that 66-88% of patients have lost smell and/or taste due to COVID-19 infection, the American Academy of Otolaryngology-Head and Neck Surgery and World Health Organization (WHO) have added anosmia and ageusia to the list of symptoms of COVID-19. The prognosis of such deficits seems variable. Some reported recovery within few weeks; while many reported persistence of deficits for several months or even more than a year after the onset of the condition. Furthermore, some patients developed respiratory symptoms later after anosmia while others remained asymptomatic. The exact mechanisms for these deficits are still under research. In animal models, the investigators found that coronaviruses could impair the olfactory neuroepithelium through the expression of angiotensin-converting enzyme type 2 (ACE2) in the sustentacular cells or damage the receptors. Treatment trials of post-COVID anosmia included the application of nasal corticosteroids, regular sniffing of different odors and strong scents, and treatment with antioxidants and vitamins. However, none was therapeutically effective. Previous preclinical and clinical studies have shown that treatment with neurotrophic polypeptides can promote neurological recovery for many neurodegenerative and acquired nervous system diseases. As the olfactory neurons are capable of regeneration, the researchers propose that treating patients with prolonged post-COVID anosmia or ageusia with cerebrolysin, a drug of neurotrophic and neuroprotective properties may promote recovery of olfactory and gustatory dysfunctions. Cerebrolysin is a mixture of peptides purified from pig brains, including (and not limited to) brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), nerve growth factor (NGF), and ciliary neurotrophic factor (CNTF).

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 100 participants
Allocation: N/A
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: The Effectiveness of Cerebrolycin for Treatment of Post-covid Olfactory and Gustatory Dysfunctions: A Pilot Study
Actual Study Start Date : August 1, 2020
Actual Primary Completion Date : February 28, 2021
Actual Study Completion Date : March 30, 2021

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Olfactory and gustatory disorders after covid 19 infection
Cerebrolysin Dose:10 ml ampoule (1ml contains 215.2 mg cerebrolysin) once daily through intramuscular injection five times per week, for a total of 20 treatments (for 4 weeks), after which the cycle was repeated again for at least 8 more weeks.
Drug: Cerebrolysin
Cerebrolysin will be prescribed in a dose of 10 ml ampoule once daily through intramuscular injection (1ml contains 215.2 mg cerebrolysin) for five times per week, for a total of 20 treatments (for 4 weeks), after which the cycle was repeated again for at least 8 more weeks.
Other Name: Neurotropic factors

Primary Outcome Measures :
  1. The smell and taste questionnaire component of the National Health and Nutrition Examination Survey (NHNES). And the modified Arabic translated and validated sniffin' sticks odor identification test was used for objective olfactory evaluations. [ Time Frame: The within subject change in sniffin' sticks test between baseline and 12- and -24 assessment time frame ]
    The NHNES questions have been selected to characterize the variation, timing and associated-symptoms of both olfactory and gustatory systems. sniffin' sticks odor identification test, a total of 16 scents were presented via a pen device to patients for 3 seconds followed by a forced choice from 4 given options with a total possible score of 16 points. According to the results, patients were classified as normosmic (score between 12-16), hyposmic (score between 9-11) or anosmic (score 8 or below). The increase in at least 4 points from baseline indicates a clinically meaningful improvement. sniffin' sticks odor identification test has high internal reliability across a wide range of population.

Secondary Outcome Measures :
  1. The short modified version of the Questionnaire of Olfactory Disorders-Negative Statements (sQOD-NS) [ Time Frame: The within subject chage in QOD-NS between baseline and assessment frame ]
    sQOD-NS is a seven-item patient-reported outcome questionnaire including social, eating, annoyance, and anxiety questions. Each item is rated on a scale of 0-3, with higher scores reflecting better olfactory-specific QOL. The total score ranges from 0 (severe impact on QoL) to 21 (no impact on QoL).

  2. The Globas Rating for smell (GRS) [ Time Frame: 6 weeks, 12 weeks, 18 weeks and 24 weeks ]
    GRS is a single-item, global rating that asks the patient to rate his current sense of smell as follow: excellent, very good, good, fair, poor or absent

  3. The Globas Rating for taste (GRT) [ Time Frame: 6 weeks, 12 weeks, 18 weeks and 24 weeks ]
    GRT is a single-item, global rating that asks the patient to rate his current sense of taste as follow: excellent, very good, good, fair, poor or absent

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   20 Years to 60 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • A random sample of at least 100 adults with sudden hyposmia/anosmia and/or hypoageusia/ageusia during COVID-19 pandemics which persist till the onset of the study. Persisting symptoms were defined by the presence at day 30 or day 60 of anosmia/ageusia.
  • Patients who experienced persistent olfactory and/or smell manifestations after recovery from their initial acute COVID-19 illness.

Exclusion Criteria:

  • Prior neurologic, medical or psychiatric disease.
  • Other known infection at onset
  • Nasal congestion
  • Nasal polyps
  • Surgery or head trauma or radiation for head and neck cancers as may result in injury to the nerves that control smell
  • Exposure to toxic chemicals (such as pesticides and solvents)
  • Cocaine or other drug abuse

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT04830943

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Assiut University Hospitals, Faculty of Medicine
Assiut, Egypt, 71516
Sponsors and Collaborators
Assiut University
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Principal Investigator: Sherifa A Hamed, M.D. Assiut University, Faculty of Medicine
Publications of Results:
Other Publications:
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Responsible Party: Sherifa Ahmed Hamed, Professor of Neurology, Assiut University Identifier: NCT04830943    
Other Study ID Numbers: COVID-NGF/AUH_SAH/2020
First Posted: April 5, 2021    Key Record Dates
Last Update Posted: April 5, 2021
Last Verified: April 2021
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Sherifa Ahmed Hamed, Assiut University:
; anosmia
; ageusia
; cerebrolysin
Additional relevant MeSH terms:
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Respiratory Tract Infections
Pneumonia, Viral
Virus Diseases
Coronavirus Infections
Coronaviridae Infections
Nidovirales Infections
RNA Virus Infections
Lung Diseases
Respiratory Tract Diseases
Olfaction Disorders
Sensation Disorders
Neurologic Manifestations
Nervous System Diseases
Neuroprotective Agents
Protective Agents
Physiological Effects of Drugs
Nootropic Agents