Turns out they did on both mice and primates.
Unfortunately the brain development data is unconvincing
And the side effect is only evaluated after the treatment:
Another potential concern, however, emerged about 1 month before Mei was treated: the final conclusions of a primate toxicology study conducted at PriMed. The company’s report, dated 17 February 2025, concluded all four monkeys that received the therapy, whether at low or high doses, developed moderate to severe liver damage.
DougPiranha42@lemmy.world 1 day ago
How? I mean the way every drug for example is tested for safety, they give it to people (healthy volunteers) in escalating doses, and watch them for adverse effects.
For some treatments, such as gene therapy, it’s not ethical to ask a volunteer to just try it to see if it’s safe. So they look for sick people, who are consenting to risking a new treatment with unproven safety, because their other choice is to not be treated.
This is how it’s always done. I wonder what you mean when you say the treatment should be tested for safety before giving it to patients.
frongt@lemmy.zip 1 day ago
A virus that doesn’t actually do anything is how. Or a test injection that doesn’t have any virus at all, if the reaction was to something else in it.
ColeSloth@discuss.tchncs.de 23 hours ago
It has to be the exact virus or it’s irrelevant, and it kind of can’t be done.
The virus has to get to the brain and spread around and “infect” cells in order to edit the DNA. It’s why it had trillions of the virus. It needs a slow and unprepared immune response so it can do the editing.
If they did a small dose test, you just vaccinated her against the virus. Her immune system would more quickly go after and destroy the virus. They expected her to get sick. They didn’t expect it to get that bad. She needed more powerful immunosuppressants beforehand.
DougPiranha42@lemmy.world 1 day ago
Neither of those things is what the patient received. Do you mean they should test the vector without the payload on the patient? If the adverse reaction is to the vector, the patient would then experience the negative effects without a chance of getting any benefits. So why not give the real thing then? If you mean a control vector should be tested on healthy volunteers, idk, maybe, but it’s hard to come up with a relevant control that certainly doesn’t do anything to dna.
frongt@lemmy.zip 1 day ago
Yeah but she wouldn’t be fucking dead.