Drug Trials 101: What does it mean when vaccine development is put on hold?



You may not know them, but they are heroes. I’m referring to Americans who are rolling up their sleeves and getting injections to test vaccines in development to prevent COVID-19.


They are your neighbors, coworkers, and unnamed superstars you see in the grocery store, at church, and playing with their kids. They are selfless volunteers who have stepped up to take part in testing so we can all, eventually, feel safer in our world. Volunteers selected are generally healthy people of certain ages.


One man I know is a business owner, a dutiful son who takes meals to his eighty-something quarantined parents and hasn’t hugged them for eight months. He leaves the groceries on the porch, and they wave as he drives away.


Another is a nurse who knows her ER won’t be empty until a vaccine is developed to protect us. She has held the hand of many dying patients who are unable to breathe. Their families can’t be there, so she becomes the conduit for last goodbyes.


In a drug trial, a company works on creating, in a lab, potions that help our bodies build immunity to foreign invaders (today, a deadly virus). We’ve all had these concoctions in the form of smallpox vaccinations, polio shots, boosters for tetanus, and annual flu shots (you got yours already, right?). A flu shot is absolutely crucial this year. This is not optional unless you have some extraordinary reason not to get the shot.


A COVID-19 vaccine would do the same thing. Protect us. But before we can all roll up our sleeves, these unsung heroes have stepped up and have answered the call for each of us. That’s why about half of them get the active drug being tested, and the other half get no drug but a shot of water (called a placebo). Not the people giving the shots or those receiving them know if they received the active drug. That’s why the trials are called double blind (only the researchers know who got the active drug) and placebo controlled (half and half).


Then we wait.


Of course, these heroes are contacted regularly. They check in for exams and answer questionnaires about whether they have been sick or have any symptoms or side effects, of any kind, during this drug trial. They are meticulously monitored for any unusual side effects or complications.


If it appears that volunteers who, in the course of their daily lives, contracted COVID-19, and if the numbering code is revealed and researchers discover that those who came down with the virus were the ones who did not receive the live vaccine—and others who did receive the drug being tested remained healthy—then assumptions can be made that the vaccine works to protect.


It’s not that simple, but it really is. Yet now, some complications.


Two vaccine trials from two different companies have been put on hold because of “safety concerns” by one company and “unexplained illness” in a trial participant by another company racing to bring their vaccine to save the world and allow us to find a new normal in a post-COVID world.


Because these newly developed vaccines have never been used on people (normally vaccines are tried out in test tubes first and then on animals), unexpected complications may occur. Unanticipated side effects such as numbness and tingling, decrease in memory and judgment, and abnormalities in blood tests and on the tracing from the electrocardiogram (a heart test).


So when a trial participant comes down with an illness or other condition, researchers need to determine if the illness was caused by the vaccine itself (if this person received the active potion) or was caused by something else entirely unrelated to the vaccine.


When there is a serious complication, trials are paused to determine what happened. Until the question is answered, no additional volunteers enter into the trial.


You may have heard the pause referred to as using “an abundance of caution.” If it is determined that the side effect is life-threatening or a serious complication, the trial may be closed, the drug abandoned, and additional research is undertaken.


The very fact that two large vaccine trials from two different companies halted the trial clearly implies that the side effect or complication was of such a magnitude that additional patients would not be tested, nor the vaccine approved for general use, until this issue is clarified.


Despite political posturing, it seems highly improbable that a safe and effective vaccine will be available for the vast majority of us until mid-2021.


In the meantime, to protect ourselves and our families, we need to continue our personal vigilance, make smart decisions, and avoid risky situations—even when others don’t. At the end of the day, these volunteers clearly understood the importance of safety, recognized that there are uncertainties, and have helped to make our world safer. Thank you to them.

© 2020  Edward T. Creagan, MD, and Write On Ink Publishing