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Viruses, Pathogens, and Other Contaminants
During the worldwide vaccination campaign, many people are expected to
become infected and may even die.
Antivirals stop or slow viral replication. Among the antivirals, remdesivir (Gilead Sciences, Inc.) is the only FDA approved treatment; however,
its effcacy is controversial. A clinical trial conducted by WHO in October
2020 found no evidence that remdesivir reduces mortality, need for ventilation, or hospitalization duration and WHO recommends against remdesivir.
Another clinical trial reported remdesivir is superior to the placebo (Beigel
et al., 2020). Ivermectin, another antiviral, reportedly reduced the duration of
illness (Ahmed et al., 2021); however, the U.S. National Institutes of Health
(NIH) advises that there is not enough effcacy data to recommend for or
against use of ivermectin (NIH, 2021).
New antivirals designed for COVID-19 are desperately needed.
Repurposing previously approved drugs and artifcial intelligence to screen
billions of compounds are accelerating discovery of new drug leads (Service
et al., 2021). Plitidepsin, approved to treat relapsed and refractory multiple
myeloma, was 27.5 times more potent than remdesivir against SARS-CoV-2
in vitro, with limited toxicity in cell culture. Antiviral activity was mediated
through inhibition of host protein (eEF1A, eukaryotic translation elongation
factor 1A) (White et al., 2021). Targeting a host protein makes it unlikely the
virus could evolve to evade drugs. Dai et al. reported in a cover article in
Science (Dai et al., 2020) design and synthesis of two lead compounds (11a
and 11b) that target M pro, a protease that plays a pivotal role in mediating
viral replication and transcription in SARS-CoV-2. Both compounds showed
good pharmacokinetic properties in vivo, and 11a also exhibited low toxicity,
which suggests that these compounds are promising drug candidates.
Immune system mimics are another treatment. Convalescent plasma (from
patients who already had COVID-19) gained a lot of attention, but most trials
have ruled it out as an effective treatment (Katz, 2021). Perhaps the most promising news in treatment and prevention of COVID-19 (aside from vaccines) is
the monoclonal antibody treatment bamlanivimab from Eli Lily. Injection of
bamlanivimab gives immediate protection, reducing new COVID-19 infections by 80%. This drug is useful in preventing outbreaks in nursing homes
(Eli Lilly and Company, 2021; Kolata, 2021).
Finally, there are treatments that reduce the immune system’s response.
Among these, the corticosteroid, mostly dexamethasone, is widely used and is
thought to reduce the death rate (The RECOVERY Collaborative Group, 2020).
Another emerging immunomodulatory strategy addresses the “cytokine
storm” which is thought to be the cause for the most severe cases that lead
to death. Some cytokine inhibitors have been associated with reduction in
risk of death, but as with most treatments, more research is needed (Khan
et al., 2021). A drug normally used for treatment of obsessive-compulsive
disorder, fuvoxamine, was studied in a small clinical trial. The initial idea
came from Dr. Angela Reiersen. While lying on the couch and recovering
from COVID-19 herself, she remembered that the drug had proven effective
Viruses, Pathogens, and Other Contaminants
During the worldwide vaccination campaign, many people are expected to
become infected and may even die.
Antivirals stop or slow viral replication. Among the antivirals, remdesivir (Gilead Sciences, Inc.) is the only FDA approved treatment; however,
its effcacy is controversial. A clinical trial conducted by WHO in October
2020 found no evidence that remdesivir reduces mortality, need for ventilation, or hospitalization duration and WHO recommends against remdesivir.
Another clinical trial reported remdesivir is superior to the placebo (Beigel
et al., 2020). Ivermectin, another antiviral, reportedly reduced the duration of
illness (Ahmed et al., 2021); however, the U.S. National Institutes of Health
(NIH) advises that there is not enough effcacy data to recommend for or
against use of ivermectin (NIH, 2021).
New antivirals designed for COVID-19 are desperately needed.
Repurposing previously approved drugs and artifcial intelligence to screen
billions of compounds are accelerating discovery of new drug leads (Service
et al., 2021). Plitidepsin, approved to treat relapsed and refractory multiple
myeloma, was 27.5 times more potent than remdesivir against SARS-CoV-2
in vitro, with limited toxicity in cell culture. Antiviral activity was mediated
through inhibition of host protein (eEF1A, eukaryotic translation elongation
factor 1A) (White et al., 2021). Targeting a host protein makes it unlikely the
virus could evolve to evade drugs. Dai et al. reported in a cover article in
Science (Dai et al., 2020) design and synthesis of two lead compounds (11a
and 11b) that target M pro, a protease that plays a pivotal role in mediating
viral replication and transcription in SARS-CoV-2. Both compounds showed
good pharmacokinetic properties in vivo, and 11a also exhibited low toxicity,
which suggests that these compounds are promising drug candidates.
Immune system mimics are another treatment. Convalescent plasma (from
patients who already had COVID-19) gained a lot of attention, but most trials
have ruled it out as an effective treatment (Katz, 2021). Perhaps the most promising news in treatment and prevention of COVID-19 (aside from vaccines) is
the monoclonal antibody treatment bamlanivimab from Eli Lily. Injection of
bamlanivimab gives immediate protection, reducing new COVID-19 infections by 80%. This drug is useful in preventing outbreaks in nursing homes
(Eli Lilly and Company, 2021; Kolata, 2021).
Finally, there are treatments that reduce the immune system’s response.
Among these, the corticosteroid, mostly dexamethasone, is widely used and is
thought to reduce the death rate (The RECOVERY Collaborative Group, 2020).
Another emerging immunomodulatory strategy addresses the “cytokine
storm” which is thought to be the cause for the most severe cases that lead
to death. Some cytokine inhibitors have been associated with reduction in
risk of death, but as with most treatments, more research is needed (Khan
et al., 2021). A drug normally used for treatment of obsessive-compulsive
disorder, fuvoxamine, was studied in a small clinical trial. The initial idea
came from Dr. Angela Reiersen. While lying on the couch and recovering
from COVID-19 herself, she remembered that the drug had proven effective