Over the last few months, a drug has found its way into the headlines  in the US on a regular basis.

Mifepristone has been the subject of laws and court cases centering on  its role in medication abortion. Some people are calling for the  drug to be banned altogether, with one argument being that it  poses a safety risk to patients.

That argument has made it all  the way to the US Supreme Court. However, some abortion rights advocates and patients say that if anything,  the drug should be easier to get. After all, they argue, why should  mifepristone be tightly regulated when it’s actually safer to take  than many other drugs on the market?

And the talking point they’re using  is “Mifepristone is safer than Viagra? So today we’re going to try and get to the  bottom of this particular talking point. But we’re also going to look at the science behind why we know mifepristone, or any drug, is safe. [♪ INTRO] Mifepristone is sold under  the brand name Mifeprex, and it’s the first pharmaceutical in a pair  typically used for medication abortion.

It has other uses too, but  this is the one we’ll focus on. It blocks the effects of progesterone,  a hormone that’s important in pregnancy. Without progesterone, the fetus  detaches from the uterine wall, and the pregnancy is terminated.

A patient will typically take mifepristone  and then follow it up immediately or up to 48 hours later with a series of doses of  misoprostol, which causes contractions. Taking mifepristone and  misoprostol together can be up to 98% effective if taken early enough in pregnancy. A second dose, as needed, makes  that number more like 99% overall.

This combo is also used for  managing early miscarriages. When a miscarriage happens in the first trimester, a patient has three options: medication  management, a physical procedure, or just waiting for it to  pass naturally from the body. Doctors used to only use misoprostol if  a patient selected the medication route, but in about 30% of cases, the patients would need further doses or a physical  procedure to pass their miscarriage.

So now doctors prescribe the  mifepristone and misoprostol combo as the standard of care, and  it’s much more effective, even though this technically isn’t an  FDA-approved way to treat miscarriage. So mifepristone definitely works, and is used to provide care to a variety of people who need it. But that’s only half of what scientists  and regulators want to know when deciding if a drug should be made available to folks.

The other half is whether it’s safe to use, and regulatory processes are  designed to find that out. Mifepristone was developed in  the 1980s and first approved in China and France in 1988. After reviewing studies conducted here and abroad, the FDA approved mifepristone  in the US in the year 2000, and it’s currently approved  in more than 90 countries.

And in the US, medication abortions  account for over half of all abortions. Which creates a ton of opportunity to  collect data on the safety of mifepristone, which should make it easy to know  if it is actually safer than, our thesis here, taking Viagra. Except it’s not quite that simple.

Because no one does clinical trials,  or even indirect comparisons, between two totally different drugs  used for two different purposes. Comparing Drug A for Use A to Drug B  for Use B would cost a lot of effort and money, and wouldn’t tell doctors  anything that would help patients. Instead, clinical studies often compare whatever intervention is being tested  to the standard of care.

Standard of care can mean a lot of things,  but in the case of abortion medications, we’re generally looking at  the other things that may happen to patients who are pregnant:  surgical abortions and live birth. And what shakes out from that research  is that medication abortion has a slightly higher rate of  complications than surgical abortion, and a much lower rate of  complications than giving birth. In case it is not clear  here, I should emphasize that no one is saying that one of these  outcomes is better than the others.

It’s simply a way of looking  at the risk to patients who are in similar situations to one another. So compared to the other options for pregnancy, we know that mifepristone is safe. So where does Viagra come in?

The FDA keeps track of adverse  events after taking a drug, that is, the times and ways people were harmed. This database is available to the public. It’s called the FDA Adverse  Event Reporting System, or FAERS.

And it is not a perfect system. For one thing, while drug companies  have to report any adverse effects that they know about, like ones that  happened during clinical trials, there’s no rule that doctors or  patients have to report events. So it’s likely that FAERS undercounts  adverse events, especially minor ones.

It also doesn’t have any way of teasing apart whether the adverse event was caused by the drug. It simply says that someone was taking  a drug, and then a bad thing happened. But if you actually want to compare the safety  of two totally different types of drugs, FAERS is probably the most objective way to do so.

So as of June 2022, the FAERS database  reports 28 deaths in patients in the US who had taken mifepristone in the more  than 20 years since it’s been approved. However, about half of those  were due to things that were not directly related to the drug  itself… including several homicides. The deaths that seem more  likely to have potentially been related to the drug were  from things like infection.

So that shakes out to a death  rate of somewhere between 0.35 and 0.65 per 100,000,  depending on which cases you count. Drugs in the group that includes  Viagra, on the other hand, have a death rate of around 4 per 100,000 users. Eight times higher than mifepristone.

Again, though, comparing the  safety of two drugs used for completely different purposes is  kind of comparing apples and oranges. But the FAERS database is the best we  have when it comes to thinking about how the risks of the drugs we’re prescribing  every day stack up against each other. And it is a transparent way to look up  the risks of any drug on the market.

So if you want to use the “mifepristone  is safer than Viagra” talking point, just know that that is where it comes from. Mifepristone is definitely safe when  evaluated in the proper context, though. And its safety profile is tight enough that some healthcare advocates want  to loosen its restrictions.

See, in the US, mifepristone is currently  more regulated than most other drugs. It’s under what the FDA calls a Risk  Evaluation and Mitigation Strategy, or REMS. That program is meant to make sure  that providers are prescribing the most dangerous drugs safely and properly  monitoring the patients on them.

Let’s consider clozapine, an antipsychotic. That’s a needed treatment for some patients. But it can totally tank your  ability to fight certain infections, which could put those patients at risk.

So the REMS requires that  a prescriber be certified, the patient be made aware of the risks,  the patient’s white blood cell count be regularly checked and  reported to the REMS program, and any pharmacies that prescribe  it must also be certified. FAERS reports more than 23,000  clozapine-related deaths since 1989. REMS medications also include Turalio, an anti-tumor medication that can  cause severe and potentially fatal liver complications in around 2% of patients.

In addition to prescriber  and pharmacy certification, it requires frequent liver testing and that a  patient initially be given a limited supply. Under the REMS requirements, it used to  be that only specially-certified doctors could prescribe mifepristone,  and it had to be given directly to the patient by that doctor, in person. In the wake of the pandemic,  the FDA has made some changes that make mifepristone easier  to get, if it remains legal.

Patients can now get a prescription  through a telehealth appointment and receive the drug by  mail, and retail pharmacies can choose to become certified  to dispense mifepristone. While that doesn’t mean every corner  pharmacy now has it, these changes have made medication abortions  more accessible to many patients. Some hoops remain.

You have to find the right pharmacy if  you don’t want to go the mail-order route, and only certain healthcare  providers may prescribe mifepristone. Patients also have to sign a form saying  that they understand all the possible risks. None of which are necessarily bad things, but they are things that we  don’t do with most other drugs.

And the drugs we do do them with tend  to be much riskier than mifepristone; carrying a risk of addiction, for example. At this point, mifepristone has been  studied for more than thirty years in hundreds of thousands of people worldwide. This video has been pretty  America-centric because we’re the ones currently arguing about it, but mifepristone is being used safely in plenty of other nations too.

So if it was an especially  dangerous drug, we’d know, and either a regulatory agency or the manufacturer would likely have pulled it from the market. It does happen. Sometimes, despite our best  efforts, clinical trials will miss something important that  comes out after a drug hits the market.

For example, look at Vioxx, a  painkiller that was approved by the FDA in 1999 based on clinical  trials of about 5000 people. After it was approved, the manufacturer conducted a few studies to learn even more about the drug. Long story short, they discovered an  increased risk of heart attack and stroke, and the manufacturer pulled  Vioxx from the market in 2004.

But in the case of Mifepristone, all of the available evidence  points to the same place: it’s safe. Saying that it’s safer than Viagra is a splashy, but messy, way to make that point. But we know that there is  rigorous evidence that the FDA and medical providers are tracking to support  their policy and prescribing decisions.

Basically, the methods we use to approve and prescribe drugs are based on science. Science is a human endeavor, and  that means it is sometimes flawed. But it’s also the best thing we’ve got going to make sure things are safe for everybody.

The next step is to make sure they’re fair, too. We hope you enjoyed this video and  I hope that you know that it would not be possible to tackle tricky  subjects like this head-on without the support of our patrons. It might sound like I’m just saying  that, but I am not just saying that; you help us do what we do every day; you make this possible, especially  when it’s less ad-friendly!

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