[2] Common side effects include feeling tired, headache, rash, itchiness, and sensitivity to sunlight.

[6] Simeprevir is indicated treating chronic hepatic C (CHC) infection as a part of a triple antiviral treatment regimen consisting of two other drugs: peginterferon-alfa (PEG-IFN) and ribavirin (RBV).

[11] It is primarily effective in treating Hepatitis C virus (HCV) genotype 1 infected subjects with compensated liver disease, including cirrhosis.

[15] Other side effects may include nausea, muscle pain, difficulty breathing and increased bilirubin.

[18] In March 2015, Gilead Sciences e-mailed warnings to health care providers about nine people that began taking its hepatitis C drugs ledipasvir/sofosbuvir or sofosbuvir along with amiodarone, daclatasvir, or simeprevir developed abnormally slow heartbeats and one died of cardiac arrest.

Simeprevir is administered as one capsule once daily with pegylated interferon and ribavirin for the treatment of genotype 1 or genotype 4 chronic hepatitis C in adult people with compensated liver disease (including cirrhosis), with or without HIV-1 co-infection, who are treatment naive or who have failed previous interferon therapy.

[11] According to simeprevir's prescriber information, its efficacy in combination with peginterferon alfa and ribavirin is "substantially reduced in people with HCV genotype 1a with an NS3 Q80K polymorphism at baseline compared to people infected with HCV genotype 1a without Q80K polymorphism.

For example, calcium channel blockers (i.e. diltiazem, amlodipine) are P-gp substrates and can lead to increased concentrations of these drugs when taken with simeprevir.

[citation needed] Several studies have been testing if the virostatic mechanism of FDA approved direct acting agents, including simeprevir in combination with remdesivir (relevant drug during the Ebola epidemic 2014–2016), could be of use in the fight against the global pandemic of Sars-Cov-2.

Paritaprevir, another molecule used to treat Hepatitis type C, also showed promising results in terms of binding energy and stability of the complex formed.

[29] The advantage of working with such compounds is that they are already FDA approved antivirals, which means that clinical trial phases can be initiated more quickly.

Speed is a crucial factor, especially regarding the fight of viruses, which by nature have an extremely high mutation rate.

[29] In vitro, the viral infection of Sars-CoV-2 could be stopped, and in addition it could be observed that further proteases of the virus are inhibited, and the effect of the antiviral could thus be enhanced.

In this regard, clinical studies proving the efficiency on the organism are still lacking at present, which are required before using the drug combination on a large scale as a form of therapy against a Sars-CoV-2 infection.

[citation needed] The hepatitis drugs are considered potential inhibitors of SARS-CoV-2 Mpro in the fight against COVID-19 infection, and the binding affinity and its mechanism, as well as the stability of the complexes formed this way, may serve as a guideline or even template when it comes to designing inhibitors that specifically target this virus.