Umifenovir

Other antivirals

ATC code: J05AX13 (Umifenovir)

Mechanism of action

The manufacturer claims inhibition of influenza virus envelope fusion with endosomal membranes, blocking cell entry. Immunomodulatory and interferon-inducing effects are also claimed. Clinical data supporting the proposed mechanism come primarily from Russian and Chinese publications and have not been replicated in independent international studies.

Indications

Acute respiratory viral infection

Not recommended

Umifenovir is not mentioned in international clinical guidelines for the treatment or prevention of viral upper respiratory infection. URI is fundamentally a self-limited viral illness not requiring etiotropic therapy. Symptomatic care (antipyretics, decongestants if needed, humidification, adequate hydration) is the only approach supported by international guidelines.

Sources

COVID-19

Not recommended

The WHO Therapeutics and COVID-19 Living Guideline does not include umifenovir among agents with proven clinical efficacy for COVID-19. Agents with established benefit include nirmatrelvir/ritonavir in high-risk outpatients, remdesivir, corticosteroids, and tocilizumab in hospitalized patients.

Sources

WHO: Clinical management of severe acute respiratory infection when COVID-19 is suspected (2023)

Influenza

Not recommended

Umifenovir is not mentioned in international guidelines for influenza management in adults (WHO, IDSA, NICE). A 2014 Cochrane Review found insufficient data to assess clinical efficacy. First-line international options for influenza include oseltamivir, zanamivir, and baloxavir (agents with proven efficacy in independent multicenter RCTs).

Sources

Practical notes

Russian practice note

Umifenovir is widely used in the Russian Federation under the brand names Arbidol, Arpeflu, Afludol, and Arbidol Maximum. It is included in the Russian Ministry of Health clinical guidelines for ARI and influenza and in various regional protocols. This creates a divergence from international practice that clinicians and patients should be aware of when deciding on use. The choice between international and Russian guidelines is a clinical decision made by the treating physician based on all circumstances.

Common myths

Myth: 'Arbidol helps prevent flu'. Fact: preventive efficacy has not been confirmed in international sources. Proven measures include annual vaccination, hand hygiene, and social distancing during epidemics. Myth: 'if it is approved, it works'. Fact: registration in the ГРЛС and inclusion in Russian Ministry of Health guidelines are not equivalent to an international evidence base. These are different approaches to efficacy assessment.

Safety

Contraindications

Hypersensitivity to any component
Age under 3 years (most RU formulations)

Serious adverse effects

Serious adverse events are rarely described in available sources, partly reflecting limited independent investigation

Common adverse effects

Per manufacturer label — rare, mostly allergic reactions

Pregnancy

Safety data in pregnancy are limited. International sources do not include recommendations.