Coronavirus treatments: Remdesivir, hydroxychloroquine and vaccines for COVID-19
The coronavirus has spread across the globe with speed and ferocity, reaching almost every country on the planet. The world has been sent into lock down in an attempt to flatten the curve and prevent health care systems from being overwhelmed. Major events, including the Tokyo Olympics, have been postponed or canceled altogether. As health authorities and governments continue to mitigate extensive transmission in the community, scientists and researchers are turning their attention to another goal: Development of treatments and vaccines.
Since coronavirus was first discovered as the causative agent of COVID-19, scientists have been racing to get a better understanding of the virus' genetic makeup and unravel how to effectively treat infections. There's no cure and medical specialists can only treat the symptoms of the disease. Many different treatment options have been proposed and some older drugs seem to be associated with positive outcomes -- but much more work is required. However, the long-term strategy to combat COVID-19, which has spread to every continent on Earth besides Antarctica, is to develop a vaccine.
Developing new vaccines takes time, and they must be rigorously tested and confirmed safe via clinical trials before they can be routinely used in humans. Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases in the US, has frequently stated that a vaccine is at least a year to 18 months away. Experts agree there's a ways to go yet.
Vaccines are incredibly important in the fight against disease. We've been able to keep a handful of viral diseases at bay for decades because of vaccine development. Even so, there exists confusion and unease about their usefulness. This guide explains what vaccines are, why they are so important and how scientists will use them in the fight against the coronavirus. It also discusses the current treatment options being used and those that show promise in hospitals.
What is a vaccine?
A vaccine is a type of treatment aimed at stimulating the body's immune system to fight against infectious pathogens, like bacteria and viruses. They are, according to the World Health Organization, "one of the most effective ways to prevent diseases."
The human body is particularly resilient to disease, having evolved a natural defense system against nasty disease-causing microorganisms like bacteria and viruses. The defense system -- our immune system -- is composed of different types of white blood cells that can detect and destroy foreign invaders. Some gobble up bacteria, some produce antibodies which can tell the body what to destroy and take out the germs, and other cells memorize what the invaders look like, so the body can respond quickly if they invade again.
Vaccines are a really clever fake-out. They make the body think it's infected so it stimulates this immune response. For instance, the measles vaccine tricks the body into thinking it has measles. When you are vaccinated for measles, your body generates a record of the measles virus. If you come into contact with it in the future, the body's immune system is primed and ready to beat it back before you can get sick.
What's in a vaccine?
Vaccines contain a handful of different ingredients depending on their type and how they aim to generate an immune response. However, there's some commonality between them all.
The most important ingredient is the antigen. This is the part of the vaccine the body can recognize as foreign. Depending on the type of vaccine, an antigen could be molecules from viruses like a strand of DNA or a protein. It could instead be weakened versions of live viruses. For instance, the measles vaccine contains a weakened version of the measles virus. When a patient receives the measles vaccine, their immune system recognizes a protein present on the measles virus and learns to fight it off.
A second important ingredient is the adjuvant. An adjuvant works to amplify the immune response to an antigen. Whether a vaccine contains an adjuvant depends on the type of vaccine it is.
Some vaccines used to be stored in vials that could be used multiple times and, as such, contained preservatives that ensured they would be able to sit on a shelf without growing other nasty bacteria inside them. One such preservative is thimerosal, which has garnered a lot of attention because it contains trace amounts of easily cleared ethylmercury. Its inclusion in vaccines hasn't been shown to cause harm, according to the CDC. In places like Australia, single-use vials are now common, and thus preservatives such as thimerosal are no longer necessary in most vaccines.
In developing a vaccine for SARS-CoV-2, scientists need to find a viable antigen that will stimulate the body's immune system into defending against infection.
Why does vaccine production take so long? There are many steps involved and a lot of regulatory hurdles to jump through.
"For any medicine to be sold it needs to go through the standard process of clinical trials including phase 1 [to] 3 trials," said Bruce Thompson, dean of health at Swinburne University in Australia. "We need to ensure that the medicine is safe, will not do harm, and know how effective it is."
Scientists can't assume their vaccine design will just work -- they have to test, test and test again. They have to recruit thousands of people to ensure the safety of a vaccine and how useful it will be. The process can be broken down into six phases:
Vaccine design: Scientists study a pathogen and decide on how they will get the immune system to recognize it.
Animal studies: A new vaccine is tested in animal models for disease to show that it works and has no extreme adverse effects.
Clinical trials (phase I): These represent the first tests in human beings and test the safety, dose and side effects of a vaccine. These trials only enroll a small cohort of patients.
Clinical trials (phase II): This is a deeper analysis of how the drug or vaccine actually works biologically. It involves a larger cohort of patients and assesses the physiological responses and interactions with the treatment. For instance, a coronavirus trial may assess if a vaccine stimulates the immune system in a certain way.
Clinical trials (phase III): The final phase of trials sees an even greater amount of people tested over a long period of time.
Regulatory approval: The final hurdle sees regulatory agencies, like the US Food and Drug Administration, the European Medicines Agency and Australia's Therapeutic Goods Administration, take a look at the available evidence from experiments and trials and conclude whether a vaccine should be given the all-clear as a treatment option.
Traditionally, then, it could take a decade or more for a new vaccine to go from design to approval. In addition, once the regulatory processes have concluded a vaccine is safe, the drug companies have to send production into overdrive, so they can manufacture enough of the vaccine to increase immunity in the wider population.
With SARS-CoV-2, the process is being expedited in some instances. As STAT news reports, the vaccine in development by Moderna has moved from design straight into Phase I clinical trials of its mRNA vaccine, skipping tests in animal models. Those tests will take place at Seattle's Kaiser Permanente Washington Health Institute, and patients are now being enrolled.
Since coronavirus was first discovered as the causative agent of COVID-19, scientists have been racing to get a better understanding of the virus' genetic makeup and unravel how to effectively treat infections. There's no cure and medical specialists can only treat the symptoms of the disease. Many different treatment options have been proposed and some older drugs seem to be associated with positive outcomes -- but much more work is required. However, the long-term strategy to combat COVID-19, which has spread to every continent on Earth besides Antarctica, is to develop a vaccine.
Developing new vaccines takes time, and they must be rigorously tested and confirmed safe via clinical trials before they can be routinely used in humans. Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases in the US, has frequently stated that a vaccine is at least a year to 18 months away. Experts agree there's a ways to go yet.
Vaccines are incredibly important in the fight against disease. We've been able to keep a handful of viral diseases at bay for decades because of vaccine development. Even so, there exists confusion and unease about their usefulness. This guide explains what vaccines are, why they are so important and how scientists will use them in the fight against the coronavirus. It also discusses the current treatment options being used and those that show promise in hospitals.
What is a vaccine?
A vaccine is a type of treatment aimed at stimulating the body's immune system to fight against infectious pathogens, like bacteria and viruses. They are, according to the World Health Organization, "one of the most effective ways to prevent diseases."
The human body is particularly resilient to disease, having evolved a natural defense system against nasty disease-causing microorganisms like bacteria and viruses. The defense system -- our immune system -- is composed of different types of white blood cells that can detect and destroy foreign invaders. Some gobble up bacteria, some produce antibodies which can tell the body what to destroy and take out the germs, and other cells memorize what the invaders look like, so the body can respond quickly if they invade again.
Vaccines are a really clever fake-out. They make the body think it's infected so it stimulates this immune response. For instance, the measles vaccine tricks the body into thinking it has measles. When you are vaccinated for measles, your body generates a record of the measles virus. If you come into contact with it in the future, the body's immune system is primed and ready to beat it back before you can get sick.
What's in a vaccine?
Vaccines contain a handful of different ingredients depending on their type and how they aim to generate an immune response. However, there's some commonality between them all.
The most important ingredient is the antigen. This is the part of the vaccine the body can recognize as foreign. Depending on the type of vaccine, an antigen could be molecules from viruses like a strand of DNA or a protein. It could instead be weakened versions of live viruses. For instance, the measles vaccine contains a weakened version of the measles virus. When a patient receives the measles vaccine, their immune system recognizes a protein present on the measles virus and learns to fight it off.
A second important ingredient is the adjuvant. An adjuvant works to amplify the immune response to an antigen. Whether a vaccine contains an adjuvant depends on the type of vaccine it is.
Some vaccines used to be stored in vials that could be used multiple times and, as such, contained preservatives that ensured they would be able to sit on a shelf without growing other nasty bacteria inside them. One such preservative is thimerosal, which has garnered a lot of attention because it contains trace amounts of easily cleared ethylmercury. Its inclusion in vaccines hasn't been shown to cause harm, according to the CDC. In places like Australia, single-use vials are now common, and thus preservatives such as thimerosal are no longer necessary in most vaccines.
In developing a vaccine for SARS-CoV-2, scientists need to find a viable antigen that will stimulate the body's immune system into defending against infection.
Why does vaccine production take so long? There are many steps involved and a lot of regulatory hurdles to jump through.
"For any medicine to be sold it needs to go through the standard process of clinical trials including phase 1 [to] 3 trials," said Bruce Thompson, dean of health at Swinburne University in Australia. "We need to ensure that the medicine is safe, will not do harm, and know how effective it is."
Scientists can't assume their vaccine design will just work -- they have to test, test and test again. They have to recruit thousands of people to ensure the safety of a vaccine and how useful it will be. The process can be broken down into six phases:
Vaccine design: Scientists study a pathogen and decide on how they will get the immune system to recognize it.
Animal studies: A new vaccine is tested in animal models for disease to show that it works and has no extreme adverse effects.
Clinical trials (phase I): These represent the first tests in human beings and test the safety, dose and side effects of a vaccine. These trials only enroll a small cohort of patients.
Clinical trials (phase II): This is a deeper analysis of how the drug or vaccine actually works biologically. It involves a larger cohort of patients and assesses the physiological responses and interactions with the treatment. For instance, a coronavirus trial may assess if a vaccine stimulates the immune system in a certain way.
Clinical trials (phase III): The final phase of trials sees an even greater amount of people tested over a long period of time.
Regulatory approval: The final hurdle sees regulatory agencies, like the US Food and Drug Administration, the European Medicines Agency and Australia's Therapeutic Goods Administration, take a look at the available evidence from experiments and trials and conclude whether a vaccine should be given the all-clear as a treatment option.
Traditionally, then, it could take a decade or more for a new vaccine to go from design to approval. In addition, once the regulatory processes have concluded a vaccine is safe, the drug companies have to send production into overdrive, so they can manufacture enough of the vaccine to increase immunity in the wider population.
With SARS-CoV-2, the process is being expedited in some instances. As STAT news reports, the vaccine in development by Moderna has moved from design straight into Phase I clinical trials of its mRNA vaccine, skipping tests in animal models. Those tests will take place at Seattle's Kaiser Permanente Washington Health Institute, and patients are now being enrolled.
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