Comment by abeppu | Hacker News Reader

Comment by abeppu | Hacker News Reader

I'm a bit confused by the timing of this. Here's a press release from only a couple months ago, in which a Moderna partnership on an mRNA vaccine showed some benefit in macaques, but mostly in delaying infection (i.e. most macaques in the treatment group still got SHIV). Only two of seven in the treatment group actually remained uninfected. It sounded like researches wanted to refine and validate their protocol before moving to human trials.

> “We are now refining our vaccine protocol to improve the quality and quantity of the VLPs produced. This may further increase vaccine efficacy and thus lower the number of prime and boost inoculations needed to produce a robust immune response. If confirmed safe and effective, we plan to conduct a Phase 1 trial of this vaccine platform in healthy adult volunteers,” said Dr. Lusso.

I interpreted "If confirmed safe and effective" to mean that more animal tests would happen.

https://www.nih.gov/news-events/news-releases/experimental-m...

2 out of 7 macaques didn't get infected after 13 weekly (anally administered) exposures to SHIV. The other 5 averaged 8 exposures before infection took place vs 3 exposures in the control group.

That's actually pretty good at preventing infection - 28.5% avoided infection completely, with the remainder clearly having a much more robust immunity than control.

I mean, it seems like it did _something_ meaningful. But if you were part of an at-risk population, how promising would you really consider an animal trial that, for most treatment subjects, delayed infection by 5 weeks? Note, these animals had received multiple vaccines/boosters spaced out over a year before they were exposed to SHIV, i.e they spent 10x as long being vaccinated as they resisted infection.

Better than nothing. Maybe not enough for me to stop whatever other practices I'm doing to reduce risk, but it seems like a good shield in case one of those others fail.

But the alternative isn't nothing.

E.g. one class of alternatives is PrEP which is very effective, well-tolerated in many patients, and depending on country, pretty affordable. Oh, maybe for various reasons, regularly getting and taking pills is difficult for some populations, and a series of injections makes more sense? Subdermal injections for PrEP are also in the works and look like they would work for more than a year.

I would love there to be a really highly effective vaccine. But PrEP sets the bar relatively high for a vaccine to actually be an improvement, right?

https://www.cdc.gov/hiv/risk/prep/index.html https://www.aidsmap.com/news/mar-2021/reformulated-islatravi...

Sort of. There are side effects, which might or.might not be bad for any individual. And of course you can forget to take daily medication. Can the vaccine be combined is an open question.

I’m curious how that compares to PrEP but I suppose both would be better than one.

"PrEP reduces the risk of getting HIV from sex by about 99% when taken as prescribed," according to the CDC: https://www.cdc.gov/hiv/basics/prep/prep-effectiveness.html

It’s hot tech, maybe driven by the desire to pump share prices.

Reply on news.ycombinator.com