6 ms·

So, umm, how do you test this vaccine? Are the participants expected to have unprotected sex with HIV-positive people?

ProjectArcturis 5y ago
No, you give it to 10k people, and give a placebo to another 10k, and let them live their lives, and after 5 years or so you see how many of each group have contracted HIV.
- jdavis703 5y ago
  The participants can have unprotected sex with HIV+ people if they want. It’s like the COVID-19 vaccine trials. The study designers didn’t set any parameters around mask use, social distancing, etc. It’s up to each participant to apply harm reduction practices as they see fit.
  - koheripbal 5y ago
    Notably covid vaccines were approved early because idiots in both arms didn't wear masks, and those in the control arms got very sick and died soon after the trial began.
- missedthecue 5y ago
  What is the statistical likelihood of someone in a 10,000 sample size of people catching HIV in any 5 year period? Probably less than 1%?
  - icegreentea2 5y ago
    Depends where you sample from. In the USA, estimated new HIV infections in 2019 35k. Assuming 350 million Americans, that gives a very rough estimate of 1 case out of 10,000 per year. You can enrich this by shifting target population. You could do this in the USA by targetting high risk communities, or by moving the trial overseas. An trial in the USA with 10k in each arm could very likely be constructed to generate at least 10 cases per year. Likely up to 50. https://www.hiv.gov/hiv-basics/overview/data-and-trends/statistics https://www.hiv.gov/hiv-basics/overview/data-and-trends/stat...
- tannhauser23 5y ago
  They're asking for 50-ish volunteers ATM.
  - icegreentea2 5y ago
    Yeah, it's a phase 1 trial. In phase 1 they aren't even really looking at if the vaccine is effective, they're making sure that it's safe/side effects are reasonable, and maybe getting some dosage information out of it.
JBorrow 5y ago
What you just described is a 'Challenge Trial'. These have been avoided for COVID and would likely be avoided for other diseases too on ethical grounds. For a common cold, or other lower-impact disease, you could do a challenge trial.
dempedempe 5y ago
The Bug Chasers would make good volunteers. https://en.wikipedia.org/wiki/Bugchasing https://en.wikipedia.org/wiki/Bugchasing
- cblconfederate 5y ago
  Looks like finding participants for a challenge trial won't be hard.

No, you give it to 10k people, and give a placebo to another 10k, and let them live their lives, and after 5 years or so you see how many of each group have contracted HIV.

jdavis703 5y ago
The participants can have unprotected sex with HIV+ people if they want. It’s like the COVID-19 vaccine trials. The study designers didn’t set any parameters around mask use, social distancing, etc. It’s up to each participant to apply harm reduction practices as they see fit.
- koheripbal 5y ago
  Notably covid vaccines were approved early because idiots in both arms didn't wear masks, and those in the control arms got very sick and died soon after the trial began.
missedthecue 5y ago
What is the statistical likelihood of someone in a 10,000 sample size of people catching HIV in any 5 year period? Probably less than 1%?
- icegreentea2 5y ago
  Depends where you sample from. In the USA, estimated new HIV infections in 2019 35k. Assuming 350 million Americans, that gives a very rough estimate of 1 case out of 10,000 per year. You can enrich this by shifting target population. You could do this in the USA by targetting high risk communities, or by moving the trial overseas. An trial in the USA with 10k in each arm could very likely be constructed to generate at least 10 cases per year. Likely up to 50. https://www.hiv.gov/hiv-basics/overview/data-and-trends/statistics https://www.hiv.gov/hiv-basics/overview/data-and-trends/stat...
tannhauser23 5y ago
They're asking for 50-ish volunteers ATM.
- icegreentea2 5y ago
  Yeah, it's a phase 1 trial. In phase 1 they aren't even really looking at if the vaccine is effective, they're making sure that it's safe/side effects are reasonable, and maybe getting some dosage information out of it.

JBorrow 5y ago

What you just described is a 'Challenge Trial'. These have been avoided for COVID and would likely be avoided for other diseases too on ethical grounds. For a common cold, or other lower-impact disease, you could do a challenge trial.

dempedempe 5y ago

The Bug Chasers would make good volunteers. https://en.wikipedia.org/wiki/Bugchasing https://en.wikipedia.org/wiki/Bugchasing

cblconfederate 5y ago
Looks like finding participants for a challenge trial won't be hard.