- Developing new drugs and vaccines is an expensive and time consuming endeavor.
- In addition, many promising treatments will simply fail to make it through the process.
- It may be years before a drug is developed.
- But experts remain hopeful a vaccine could potentially be available by the end of the year.
Since the beginning of the COVID-19 pandemic, the race has been on to develop an effective drug or vaccine to help in the fight against the disease.
While many people are hoping this will happen quickly, making it possible to return to “normal” life once more, experts say it may take much longer than many people realize before an effective drug or vaccine is developed.
And it may take even longer still before it’s widely available.
How new drugs and vaccines are developed
According to Dr. Thad Stappenbeck, chair of the department of inflammation and immunity at Cleveland Clinic’s Lerner Research Institute, new drugs and vaccines go through four phases of testing:
The goal of this phase is to determine whether it’s safe. In addition, it assesses side effects.
This phase usually involves using a small group of healthy people, says Stappenbeck.
In this phase, work is done to determine the maximum tolerated dose, the optimal schedule for dosing, and whether the immune system is responding as desired.
These studies usually involve a few hundred participants, Stappenbeck says.
If the drug or vaccine appears to be effective at this stage, it will move on to phase II. However, many studies will halt here and never proceed further because of poor results.
At this point, testing will be done on a larger group of people, usually numbering in the thousands.
Stappenbeck notes that people who are at increased risk for infection may be included at this stage of testing.
These studies seek to gather additional information about the treatment’s safety and effectiveness. They may extend testing to additional populations, such as children and pregnant women, who were previously excluded.
Stappenbeck further explains that in all phases of testing, certain controls are used.
There will be two groups of participants: those who are receiving the therapeutic agent and those who are receiving an inactive placebo.
They’re assigned to one of these two groups at random, with neither the participants nor their caregivers knowing which group they’re in.
Stappenbeck says these controls are used increasingly as the drugs and vaccines progress through each phase.
Why it will probably take longer to get a COVID-19 drug or vaccine
Nikolai Petrovsky, PhD, director of endocrinology at Flinders Medical Centre and professor of medicine at Flinders University in Australia, explains that it usually takes around 10 to 15 years to develop a new drug or vaccine due to the complexity of the process.
It can be very difficult to compress this process into a matter of months.
A delay in receiving a needed piece of equipment or an important reagent might not significantly affect the overall timeline when you’re working on a scale of years, he says.
However, the effect can be “massive” when you’re trying to develop a vaccine in a matter of months.
In addition, Petrovsky says, we need to consider the impact of the pandemic itself.
“Because we are in a pandemic, this means nothing is working normally so everything is slowed down by up to tenfold,” Petrovsky said.
Petrovsky further points out that, even under the best of circumstances, promising new treatments will often fail to make it through the process.
One common reason for failure, he says, is that the underlying science is simply not good enough. Perhaps the treatment isn’t effective enough, or it’s targeting the wrong receptor or virus pathway.
Another common reason for failure is that something unexpected — such as a severe side effect or a safety issue — emerges during clinical trials.
Finally, drug development is a very expensive process, with costs of up to $2 billion being typical. So, a lack of financing might be a barrier.
Where we are right now in the search for an effective COVID-19 treatment
As far as drug treatments, Petrovsky points to dexamethasone and remdesivir as being the most promising at the moment.
“Dexamethasone so far is the biggest breakthrough as it is cheap, readily available, and has been shown to improve clinically significant outcomes,” Petrovsky said.
“Remdesivir may have some modest benefits, although whether these are clinically meaningful and worth the expense remains a matter of debate,” he added.
Petrovsky says chloroquine and hydroxychloroquine have been the biggest failures so far. “Despite all the hype, they have delivered effectively nothing,” he explained.
Regarding potential vaccines, Petrovsky says the most effective vaccines are those based on traditional protein-based approaches.
These include the inactivated whole-virus approaches being used by several Chinese companies, as well as the recombinant vaccine approaches being utilized by companies such as Vaxine, Novavax, and Sanofi.
So far, these have shown high levels of protection when tested on animals, he says.
At the other end of the spectrum are adenovirus vaccines, Petrovsky says. These have failed to control virus replication in animal models. In addition, they can cause high levels of side effects in humans, including dangerous fevers.
Also, since they use live viruses, they can’t be used in anyone with a compromised immune system.
A vaccine that’s both safe and effective on all groups of people is needed to stop the pandemic, he explains.
What’s the soonest we might expect a drug or vaccine to be available?
A true antiviral treatment for COVID-19 will take years to develop, says Petrovsky.
What’s more likely in the short term is that we will be using currently existing drugs like dexamethasone that can suppress inflammation pathways.
While the timing on a vaccine is hard to predict, Stappenbeck says that if the earliest vaccines in trials make it through phase III, we could begin to see vaccine production and delivery by late this year or early next year.
Many of the companies are producing large amounts of the vaccines at the same time as they continue testing them to have them ready to go as soon as they’re approved.
Everything hinges on these vaccines being proven safe and effective, however.
The bottom line
Developing new drugs and vaccines is a costly, complicated, and time consuming process. It can be very difficult to condense what would normally be years of work into a few short months.
In addition, even under the best of circumstances, many drugs and vaccines will fail.
While researchers are working very hard to develop a safe, effective drug or vaccine for COVID-19, it may take longer than we’d like.
It may be years before we see a new drug treatment. If all goes well, however, we might see a vaccine in late 2020 or early 2021.