To conduct an open-label randomized controlled trial on a short course of interferon β-1b and clofazimine combination treatment for patients hospitalized for COVID-19 infection. To assess its safety and clinical efficacy.

The novel coronavirus (SARS-CoV-2), is a single-stranded RNA coronavirus. The virus was first isolated from patients presented with pneumonia in Wuhan in December 2019.Sequences of the Wuhan betacoronavirus show similarities to betacoronaviruses found in bats, sharing a common ancestor with the 2003 SARS coronavirus (SARS-CoV) and the bat coronavirus HKU9-1, a virus found in fruit bats. Similar to SARS-CoV, it is a member of Beta-CoV lineage B. Five genomes of the novel coronavirus have been initially isolated and reported including BetaCoV/Wuhan/IVDC-HB-01/2019, BetaCoV/Wuhan/IVDC-HB-04/2020, BetaCoV/Wuhan/IVDC-HB-05/2019, BetaCoV/Wuhan/WIV04/2019, and BetaCoV/Wuhan/IPBCAMS-WH-01/2019 from the China CDC.

The SARS-CoV-2 has since spread from China to the rest of the world. As of 1 July 2020, more than 10 million people been confirmed to have infected by SARS-CoV-2, resulting in more than 500,000 deaths. No specific antiviral treatment for the SARS-CoV-2 is currently available, but existing medication could be repurposed.

Genetic sequencing demonstrated similarity of the SARS-CoV-2 to the SARS-CoV and MERS CoV.2 We expect patients infected with the SARS-CoV-2 will also present similarly with initial upper respiratory tract symptoms including fever, cough, sputum, myalgia and shortness or breath. More severe cases might complicate with pneumonia and required ventilatory or ECMO support. According to our previous studies in 2003 on patients hospitalized for severe SARS-CoV, the viral load peaked between day 7 from symptoms onset and coincided with clinical deterioration of pneumonia and respiratory failure, with majority of the patients required intensive care support. Higher viral load isolated from different human system also correlated with worsened SARS manifestation and complications.

Previously, the investigators have demonstrated that interferon β-1b, commonly used in the treatment of multiple sclerosis and lopinavir/ ritonavir, also demonstrated to improve the outcome of MERS-CoV infection in a non-human primate model of common marmoset.7

More recently, the investigators have demonstrated that the triple combination of interferon β-1b, lopinavir/ ritonavir and ribavirin was significantly more effective in alleviating symptoms and respiratory SARS-CoV-2 viral load than lopinavir/ ritonavir with ribavirin or lopinavir/ ritonavir alone, suggesting that interferon β-1b might be the most potent antiviral among the three.

Another in-vitro study on an oral antimicrobial clofazimine for treatment of non-tuberculous mycobacterium infection has been proven to reduce SARS-CoV-2 viral load.

Therefore, the investigators propose to perform a prospective open-label randomised controlled trial among adult patients hospitalised after July 2020 for virologically confirmed SARS-CoV-2 infection. Patients will be randomly assigned to one of the three groups: group A: a 3-day course of 3 doses of subcutaneous injection of interferon β-1b 1mL (0.5mg; 16 million IU) consecutively on day 1 to day 3 and oral clofazimine 100mg twice daily on day 1, then 100mg daily for 2 days plus standard care, or group B: oral clofazimine 100mg twice daily on day 1, then 100mg daily for 2 days plus standard care, or group C: standard care alone (1:1:1).

Inclusion Criteria:

1. Recruited subjects include all adult patients 18 years or above hospitalized for virologic confirmed SARS-CoV-2 infection.
2. All subjects give written informed consent. For patients who are critically ill, requiring ICU, ventilation or confused, informed consent will be obtained from spouse, next-of-kin or legal guardians.
3. Subjects must be available to complete the study and comply with study procedures. Willingness to allow for serum samples to be stored beyond the study period, for potential additional future testing to better characterize immune response

Exclusion Criteria:

1. Inability to comprehend and to follow all required study procedures.
2. Allergy or severe reactions to the study drugs
3. Patients taking medication that will potentially interact with l interferon beta-1b or clofazimine
4. Patients with known history of severe depression
5. Received an experimental agent (vaccine, drug, biologic, device, blood product, or medication) within 1 month prior to recruitment in this study or expect to receive an experimental agent during this study.
6. To participate in an unrelated trial during the current clinical trial. Nevertheless, the patients have the right to withdraw from the current clinical trial to join another clinical trial.
7. Have a history of alcohol or drug abuse in the last 5 years.
8. Have any condition that the investigator believes may interfere with successful completion of the study

To share anonymised participant data

Within 12 months of study published

To be approved by the HKU/ IRB clinical trial study panel of valid research purpose