Vaccine development process and stages

Anyway, one topic that is definitely affecting all of our lives directly or indirectly is the novel coronavirus epidemics/outbreak (COVID-19). Dr. Anthony Fauci, director of the National Institute of Allergies and Infectious Diseases, talks about developing a Covid-19 vaccine, reopening schools and whether or not there should be a national mandate to wear face masks. He spoke to Bloomberg’s David Westin. I want you to see at least the first 20 minutes and pay attention to some concepts will be discussed soon in the first and second lecture:

Link: https://www.youtube.com/watch?v=_XkOCM1kNBg

1) What are the differences between phase I, phase II and phase III trials?
2) Why are they needed?
3) Can we just give vaccines that show promise in animal studies/preclinical data given this urgent need?

“Randomized, placebo controlled trials (PCTs) are widely considered to be the most
rigorous method of evaluating the efficacy of treatment or prevention interventions.
To be ethical, clinical research requires balancing rigorous science with the
protection of human subjects. Most people accept the use of placebo controls in
trials for conditions with no effective treatment. However, PCTs raise ethical
concerns when a proven effective treatment exists, since randomizing subjects to a
placebo exposes them to the potential harms of nontreatment. The choice of a PCT
design over other designs, such as active-controlled superiority or non-inferiority
trials, therefore requires ethical justification.”

Source: Millum, J., and Grady, C. (2013). The ethics of placebo-controlled trials:
methodological justifications. Contemporary clinical trials, 36(2), 510-514.

1. Based on the abstract regarding the ethics of using placebo in clinical research,
please list all the circumstances in which you think it is ethical to use placebo in
human trials. You should support your answer with examples from the literature.

2. The ethical use of placebo is frequently subject to many controversies in clinical
trials, as it involves the use of an inert pill / sham intervention in a group of patients.
Regarding that, in which of the situations below do you think the use of placebo is
definitely unethical. Provide a rationale for your answer.

A. When it fits the principle of equipoise.

B. When patients are not informed they are in a placebo-controlled trial, as to
guarantee blinding.

C. When it is used for a short period of time in chronic diseases in which the delay of
active treatment does not pose a significant harm.

D. When the parents are well explained and sign the informed consent form, children
should not receive placebo as they do not understand what placebo means.
Why? (Justify your choice)