[♩INTRO].

More than eighteen hundred people have died so far in the second largest Ebola outbreak in history. But doctors on the front lines now have a new weapon.

Two of them, actually, because a clinical trial in the Democratic Republic of the Congo revealed two new treatments which can cure the disease. The Ebola virus kills about three-quarters of people who don't receive medical care. And obviously, that's a lot.

But what's really scary how many still die with treatment. The standard treatment is a drug called ZMapp, but it only brings the average mortality rate down to 49%. So in November of 2018, researchers started a clinical trial to test several new drugs.

One was an antiviral compound called Remdesivir, which is designed to gum up one of the main proteins the virus needs to replicate. The other two attack the virus with antibodies: proteins made by the immune system which grab onto potential pathogens so they can be destroyed. Antibodies can be very effective treatments if you can get them to stick.

The trouble with Ebola is that it can change shape and mask itself from the immune system, so it's been hard to find an antibody that always works. So, one biotech company used special animal models to develop three different antibodies, which they then combined to make REGN-EB3 or just EB3. Other researchers looked for solutions in living people.

They managed to clone an antibody from someone who survived an Ebola outbreak in the 90s, and called that mAb114. The trial compared these three new treatments to ZMapp in nearly seven hundred patients over the past nine or so months. And unfortunately, the antiviral didn't do much.

The antibodies, though—they were amazing. A single dose of the lone antibody brought mortality rates down to 34%, and one dose of the EB3 cocktail dropped them all the way to 29%. But an even bigger win came for patients who were treated with one of these within three days of getting sick — between 89-94% of them survived!

That's so effective that the researchers decided to call off the trial right there so they could give everyone the potential cures. Now, doctors will start a new trial with just EB3 and mAb114 to see how they compare, and both drugs will be made available to people who aren't part of the research. And Ebola isn't the only deadly disease we've gotten closer to curing.

Just last week, the US FDA approved a new treatment for antibiotic-resistant tuberculosis a critical step towards getting the drugs to where they're needed most. Tuberculosis, or TB, is a bacterial lung infection. And we've had vaccines and antibiotics for it for years now.

But about ten million people around the world still get TB, and one particular strain is resistant to our usual treatment methods, making it extremely deadly. The vast majority of people who contract drug resistant TB die before they're even diagnosed, and even with treatment, only 34% of them make it. Plus, that treatment involves taking upwards of 40 pills a day for up to two years, and can have some serious side effects.

Obviously, it'd be great if we had an easier, more effective option. But developing new antibiotics is really expensive, and few companies are willing to make the investment, especially when the majority of people with TB are poor and can't afford expensive drugs. Luckily, nonprofits like the TB Alliance have stepped up.

And it's thanks to their influx of cash that the antibiotic which just won over the FDA, called pretomanid, was developed. A clinical trial of the drug which began in 2015 found that, when pretomanid was combined with two other antibiotics, almost 90% of people recovered in six months. And patients only have to take five pills a day!

That overwhelming success convinced the FDA to approve of the three-drug regimen. And when the FDA approves of something, international organizations often follow suit. But there are still challenges ahead.

Bacterial infections like TB are more common in impoverished areas of the world, so antibiotics need to be priced in a way that poorer patients can afford them. And even non-profits with the best intentions can run out of money. So they need to get manufacturers to agree to price the drug reasonably.

Those negotiations are going on right now, so let's all keep our fingers crossed. Thanks for watching this episode of SciShow News! But before you go, there's one more thing I'd like to mention.

It's not exactly news, but if you're the kind of person who likes to jazz up your jacket or backpack with an awesome pin, you might want to head on over to DFTBA.com/scishow. Our August Pin of the Month, which features the Curiosity rover, is only on sale for another week! And I know you don't want to miss out on such a stylish, adorable tribute. [♩OUTRO].