How does Pfizer identify cases of COVID-19 in its clinical trials?
How does Pfizer identify cases of COVID-19 in its clinical trials?
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Clinical trial researchers have standard definitions for routinely detecting COVID-19 cases for both symptomatic and asymptomatic individuals. There are three ways that researchers classify and identify symptomatic COVID-19 cases in clinical trials. Criteria for the first classification includes: the presence of at least one COVID-19 symptom and a positive COVID-19 test during, or within 4 days before or after, having symptoms. The second classification is the same, but also includes four additional COVID-19 symptoms defined by the CDC (fatigue, headache, nasal congestion or runny nose, nausea). Criteria for the third classification, which identifies severe COVID-19 cases in clinical trials, includes a confirmed COVID-19 test (per the above guidelines), as well as one of the following symptoms: clinical signs of severe systemic illness, respiratory failure, evidence of shock, significant acute kidney, liver, or brain dysfunction, admission to an ICU, or death. The Pfizer research protocol states individuals who do not clinically present COVID-19 (that is, asymptomatic individuals) are tested for COVID-19 antibodies. A positive asymptomatic case is defined as the presence of antibodies in an individual who had a prior negative test. By using these four definitions, researchers are able to detect COVID-19 cases in both symptomatic and asymptomatic individuals. However, the pharmaceutical company has stated that there are more data on the vaccine’s safety and efficacy for symptomatic cases, and that more data is needed to better understand the vaccine’s safety and efficacy for asymptomatic cases.
Clinical trial researchers have standard definitions for routinely detecting COVID-19 cases for both symptomatic and asymptomatic individuals. There are three ways that researchers classify and identify symptomatic COVID-19 cases in clinical trials. Criteria for the first classification includes: the presence of at least one COVID-19 symptom and a positive COVID-19 test during, or within 4 days before or after, having symptoms. The second classification is the same, but also includes four additional COVID-19 symptoms defined by the CDC (fatigue, headache, nasal congestion or runny nose, nausea). Criteria for the third classification, which identifies severe COVID-19 cases in clinical trials, includes a confirmed COVID-19 test (per the above guidelines), as well as one of the following symptoms: clinical signs of severe systemic illness, respiratory failure, evidence of shock, significant acute kidney, liver, or brain dysfunction, admission to an ICU, or death. The Pfizer research protocol states individuals who do not clinically present COVID-19 (that is, asymptomatic individuals) are tested for COVID-19 antibodies. A positive asymptomatic case is defined as the presence of antibodies in an individual who had a prior negative test. By using these four definitions, researchers are able to detect COVID-19 cases in both symptomatic and asymptomatic individuals. However, the pharmaceutical company has stated that there are more data on the vaccine’s safety and efficacy for symptomatic cases, and that more data is needed to better understand the vaccine’s safety and efficacy for asymptomatic cases.
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Clinical trial researchers have standard definitions for routinely detecting COVID-19 cases for both symptomatic and asymptomatic individuals.
There are three ways that researchers classify and identify symptomatic COVID-19 cases in clinical trials. Criteria for the first classification includes: the presence of at least one COVID-19 symptom and a positive COVID-19 test during, or within 4 days before or after, having symptoms. The second classification is the same, but also includes four additional COVID-19 symptoms defined by the CDC (fatigue, headache, nasal congestion or runny nose, nausea).
Criteria for the third classification, which identifies severe COVID-19 cases in clinical trials, includes a confirmed COVID-19 test (per the above guidelines), as well as one of the following symptoms: clinical signs of severe systemic illness, respiratory failure, evidence of shock, significant acute kidney, liver, or brain dysfunction, admission to an ICU, or death.
The Pfizer research protocol states individuals who do not clinically present COVID-19 (that is, asymptomatic individuals) are tested for COVID-19 antibodies. A positive asymptomatic case is defined as the presence of antibodies in an individual who had a prior negative test.
By using these four definitions, researchers are able to detect COVID-19 cases in both symptomatic and asymptomatic individuals. However, the pharmaceutical company has stated that there are more data on the vaccine’s safety and efficacy for symptomatic cases, and that more data is needed to better understand the vaccine’s safety and efficacy for asymptomatic cases.
Clinical trial researchers have standard definitions for routinely detecting COVID-19 cases for both symptomatic and asymptomatic individuals.
There are three ways that researchers classify and identify symptomatic COVID-19 cases in clinical trials. Criteria for the first classification includes: the presence of at least one COVID-19 symptom and a positive COVID-19 test during, or within 4 days before or after, having symptoms. The second classification is the same, but also includes four additional COVID-19 symptoms defined by the CDC (fatigue, headache, nasal congestion or runny nose, nausea).
Criteria for the third classification, which identifies severe COVID-19 cases in clinical trials, includes a confirmed COVID-19 test (per the above guidelines), as well as one of the following symptoms: clinical signs of severe systemic illness, respiratory failure, evidence of shock, significant acute kidney, liver, or brain dysfunction, admission to an ICU, or death.
The Pfizer research protocol states individuals who do not clinically present COVID-19 (that is, asymptomatic individuals) are tested for COVID-19 antibodies. A positive asymptomatic case is defined as the presence of antibodies in an individual who had a prior negative test.
By using these four definitions, researchers are able to detect COVID-19 cases in both symptomatic and asymptomatic individuals. However, the pharmaceutical company has stated that there are more data on the vaccine’s safety and efficacy for symptomatic cases, and that more data is needed to better understand the vaccine’s safety and efficacy for asymptomatic cases.
Context and background
The Pfizer vaccine is being developed and produced by Pfizer, Inc. and the biotech company BioNTech SE. It is a genetic mRNA vaccine (mRNA-1273) currently in Phase 3 clinical trials across the globe. Here is a breakdown of everything you need to know so far about this vaccine’s development.
On November 30, 2020 with primary efficacy analysis data from its Phase 3 trial, Pfizer announced its experimental COVID-19 vaccine to be 95% effective 28 days after the first of two doses. Out of approximately 44,000 total study participants, 170 came down with COVID-19. There were 162 in the placebo group and only 8 in the group that was vaccinated with the Pfizer vaccine.
The Pfizer vaccine is being developed and produced by Pfizer, Inc. and the biotech company BioNTech SE. It is a genetic mRNA vaccine (mRNA-1273) currently in Phase 3 clinical trials across the globe. Here is a breakdown of everything you need to know so far about this vaccine’s development.
On November 30, 2020 with primary efficacy analysis data from its Phase 3 trial, Pfizer announced its experimental COVID-19 vaccine to be 95% effective 28 days after the first of two doses. Out of approximately 44,000 total study participants, 170 came down with COVID-19. There were 162 in the placebo group and only 8 in the group that was vaccinated with the Pfizer vaccine.
