Many people die due to a bad drug/vaccine given to everyone?

Hi guys, I remember seeing the intro of a movie a long time ago, whereby there are a few survivors and they ask what happened, and they said that the reason why so many people died was because everyone took some sort of anti-cancer drug, and it later turned out that it caused deaths.

Now, my memory is pretty bad, so it may not have been an anti-cancer drug, it might have been a vaccine. Also, I'm not sure if people died from it, or if people simply were unable to reproduce.

If I had to guess I'd say the movie was probably made within the last 5 to 15 years ago.

Any ideas?

Thanks in advance!

There was an episode os Sargate SG1 where an alien race befriend humanity and provide a drug to cure disease and provide longevity to the human life span but the drug makes it virtually imossible to conceive. This is the aliens prefered conquest method as the population slowly dies out and they win a planet without waging a war.

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Did you know that in the 1980s movie PREDATOR the titular character was not originally portrayed by Kevin Peter Hall. It was in fact Jean-Claude Van Damme donning a much more insect inspired full body suit before he left the production which then led to the recasting and redesigning of the famous hunter.

I Am Legend?

Yes. Measles vaccine used to create a cancer cure.

I thought it might have been Children of Men, but the cause of that calamity wasn't exactly explained.

Do you remember if it turned them into Zombies too? There is a Zombie movie where a cancer drug/treatment cure was found and that's what caused the trouble. I'll try and find t if the Zombie card was played ! The start of the film I have in mind had a woman on a TV interview saying she has a cancer cure.

Just guessing... Mayhem 2017 ?

Maybe... just maybe is this one of REC movies!

Is it The Facility:

Unfortunately I don't think any of those are the movie that I saw, but I appreciate everyone's help.

The Stargate SG1 episode might be the closest, I'll have to give that a watch to be sure, but I have doubts that's it.

The way that the characters discussed the situation almost sounded like they came from the past/future to discover what happened, but I could be wrong. I remember the scene looking dystopian, very grayish and deserted. I think the characters were in military uniform.

12 Monkeys fits the going back in time to find the original virus so they can make a vaccine. The future is underground because of the virus on the surface, so it does look grayish and it's definitely dystopian. The surface is deserted/abandoned. There were guards below and they wore a uniform.