What about the Pfizer Covid 19 drug?

The Pfizer Covid19 drug is a protease inhibitor. All the protease inhibitors tested to date have failed to show efficacy against Covid19.

These include the antiviral drugs. lopinavir, ritonavir, darunavir andcobicistat have been shown in clinical trials to not be effective against Covid19.

The current FDA recommendation is to not use any protease inhibitor against Covid19 in any patient:

"Recommendations

The COVID-19 Treatment Guidelines Panel (the Panel) recommends against the use of lopinavir/ritonavir and other HIV protease inhibitors for the treatment of COVID-19 in hospitalized patients (AI).
The Panel recommends against the use of lopinavir/ritonavir and other HIV protease inhibitors for the treatment of COVID-19 in nonhospitalized patients (AIII)."

https://www.covid19treatmentguidelines.nih.go...nhibitors/

In addition lopinavir and ritonavir have significant cardiac and hepatotoxicity

The Pfiizer study is a phase 1 ascending dose trial in 60 healthy volunteers. This is the first time the drug has been used in humans.

https://clinicaltrials.gov/ct2/show/study/NCT...1#contacts