Inosine pranobex was associated with a reduction in mortality in COVID-19 by over 22%, as reported in a retrospective study utilizing complete health data from the Czech national registry
et al., International Journal of Infectious Diseases, doi:10.1016/j.ijid.2026.108519, Mar 2026
Retrospective 67,841 inosine pranobex recipients matched 1:2 with 135,682 controls from the Czech national registry, showing significantly reduced COVID-19 mortality with treatment.
Negative control outcome analyses (non-COVID mortality, cardiovascular mortality, external-cause mortality) showed no benefit, suggesting the effect is not purely a healthy-user bias. Authors note that treatment was prescribed preferentially to higher-risk patients, yet recipients still showed lower mortality, which strengthens the apparent benefit but cannot fully exclude unmeasured confounders.
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risk of death, 46.3% lower, RR 0.54, p = 0.11, treatment 42,346, control 84,692.
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risk of death, 22.0% lower, RR 0.78, p < 0.001, treatment 697 of 42,346 (1.6%), control 1,788 of 84,692 (2.1%), NNT 215, pre-omicon.
|
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risk of death, 65.0% lower, RR 0.35, p < 0.001, treatment 32 of 25,495 (0.1%), control 181 of 50,990 (0.4%), NNT 436, omicron.
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| Effect extraction follows pre-specified rules prioritizing more serious outcomes. Submit updates |
Veselý et al., 31 Mar 2026, retrospective, Czech Republic, peer-reviewed, 5 authors, study period 1 March, 2020 - 31 December, 2021.
Contact: dalibor.vesely@lf3.cuni.cz, veselydalibor@seznam.cz.
Inosine pranobex is an orally administered small-molecule immunomodulator with broad antiviral activity. It enhances natural killer cell cytotoxicity and T-lymphocyte function and promotes Th1-type cytokine responses, thereby augmenting host antiviral defenses.
Abstract:
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Inosine pranobex was associated with a reduction in mortality in COVID-19 by over 22%, as reported in a retrospective study utilizing complete health data from the Czech national registry
Dalibor Veselý 1 , ∗ , Václav ˇ Capek 2 , Ondˇ rej Šanca 3 , Jiˇ rí Beran 4 , Jiˇ rí Slíva 1
- 1 Department of Pharmacology, Third Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
- 2 Independent researcher
- 3 Institute of Health Information and Statistics of the Czech Republic, Prague, Czech Republic
- 4 Department for Tropical, Travel Medicine and Immunization, Institute for Postgraduate Medical Education, Prague, Czech Republic
a r t i c l e i n f o
Article history: Received 24 August 2025 Revised 17 February 2026 Accepted 28 February 2026
Available online xxx pranobex
Keywords: COVID-19 Pandemic Inosine Isoprinosine Mortality
Risk factor
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