As of August 24, 2020, the jury is out on your question--Can the replication and transmission of the SARS-CoV-2 (2019-nCoV) virus in humans be inhibited in a similar way by the use of oseltamivir? It could be answered definitively only in a randomized trial.
The company that manufactures Tamiflu—the branded version of oseltamivir--seems not to consider oseltamivir promising for this virus, with considerable pessimism about its use for the treatment of COVID-19.
Thus, on April 29, 2020, Roche, the manufacturer of Tamiflu, issued provided the following information about Tamiflu and COVID-19.
Tamiflu and Use in Coronavirus (COVID-19)
This response corresponds to your request for information on the use
of Tamiflu® (oseltamivir phosphate) for the treatment of novel human
This response was developed according to principles of evidence-based
medicine and includes information from case series and reports with 5
or more patients.
There are currently no medicines approved to specifically treat human
coronaviruses. Tamiflu is designed to be highly specific to the
influenza virus. Due to this high specificity, it is extremely
unlikely that Tamiflu would be effective at treating the coronavirus.
Independent laboratory testing conducted by Hong Kong University,
School of Public Health demonstrates that Tamiflu does not have any
antiviral effect on the novel coronavirus.
Two case series describe the use of oseltamivir in patients
hospitalized for COVID-19 in Wuhan, China.
The PDF document that includes this information from Roche can be found by Googling medinfo.roche.com>COVID-19>Tamiflu.
The document from Roche then provides detail on the case series.
The first case series was published in the Lancet.
In a Lancet publication describing 41 patients, 38 patients were
empirically treated upon hospital admission with oseltamivir 75 mg
twice daily along with antibiotic therapy.4 Common symptoms presented
by these patients included fever, cough, and myalgia or fatigue. All
patients had pneumonia and abnormalities in chest CT images. The
median time from onset of symptoms to hospital admission (n=41) was 7
days (range, 4-8). The median time from onset of symptoms to ICU
admission (n=16) was 1Th0.5 days (range, 8-17). Oseltamivir treatment
was administered in 12 of the 13 patients, who received ICU care, and
in 26 of the 28 patients, who did not receive ICU care. There was no
statistical difference between the proportion of oseltamivir-treated
patients admitted to the ICU compared with oseltamivir-treated
patients not admitted to the ICU (92% vs. 93%, p=0.46).
Huang C, Wang Y, Li X, et al. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China [supplementary appendix appears online]. Lancet 2020;395:497-506. https://www.ncbi.nlm.nih.gov/pubmed/31986264
The second case series was published in JAMA.
In a JAMA publication, 138 patients with COVID-19 were admitted to the
hospital at a median time of 7 days from the onset of symptoms.6 Of
the 138 patients, 124 patients received oseltamivir. The dose of
oseltamivir was adjusted based on the severity of the disease, and was
not reported. The authors noted no effective outcomes were observed.
Wang D, Hu B, Hu C, et al. Clinical Characteristics of 138 Hospitalized Patients With 2019 Novel Coronavirus-Infected Pneumonia in Wuhan, China. JAMA. E-pub Date: aheadofprint February 2020. DOI # 10.1001/jama.2020.1585 . https://www.ncbi.nlm.nih.gov/pubmed/32031570
The question of whether oseltamivir has an effect on transmissability and/or infection with the SARS-CoV-2 virus would be definitively answered in a randomized, double-blind, placebo controlled clinical trial.
On August 24, 2020, no randomized, double-blind, placebo controlled clinical trials involving oseltamivir were registered at Clinical Trials.gov.