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Doctor said Prep is only 40% effective

Oct 24, 2018

Hello Damon, this is my first time posting a question here. I have been very strict on my PrEP regimen for about 1 year already. Today i went to see my HIV specialist and he told me that PrEP is only 40% effective and that Gilead is lying to us about them wanting us to believe the 92%-99% effectiveness. He throws at me this very upsetting news, after a whole year of taking the medicine. I am 23 years old and have been a little more open to having unprotected sex. He told me he has seen countless of patients come in while taking PrEP as directed and still turn out to be HIV positive. This was all a shock to me and its very upsetting. This made think about stopping Truvada. Whats the point of taking Truvada if my doctor said its only 40% effective? I need some insight, is this really true? I thought only a handful of guys have caught HIV while taking Truvada but my doctor says he has seen many more cases.

Response from Mr. Jacobs

I am going to begin by recommending to you and anyone reading this to REPORT any doctor who is giving out such patently false and dangerous information. It is partly because of these myths and lies that PrEP uptake has been relatively low. PrEP can play a major role in ending the epidemic globally but not if healthcare workers are going to obstruct progress by stating such unscientific facts. Let's break down your doctor's irresponsibility point-by-point:

(1) There is no science nor data that has ever suggested that PrEP is 40% effective. HOWEVER -- when Iprex was first published in 2010, it did state that PrEP reduced HIV acquisitions by 44% in that study. Why so low? Because not everyone who was given the drug took the drug. When doctors talk about PrEP they are often using the "Relative Risk Reduction (RRR)" numbers which average an entire group's protection whether they took it or not. In Iprex - when they averaged the amount of protection offered by Truvada by those who took it 7 days a week, with those who took it zero days a week, they came up with 44%. But not one HIV transmission took place in any person who took the drug four or more times per week (

(2) Gilead doesn't state that the drug reduces risk by 92%-99%. They have no marketing materials that state this, as there is no grand conspiracy at work here. Those were the numbers offered in 2012 by the Iprex researchers after the data had been analyzed ( There is a big difference in data offered by scientists versus data offered by pharmaceutical companies.

(3) After even two doses of using Truvada you stopped having "unprotected" sex. PrEP is the most protected sex an HIV negative person can use to be in control of their HIV status. The more accurate term is that you are having protected sex because you are taking PrEP daily (

(4) Doctors are ethically bound to report any suspected HIV transmissions on PrEP ( Failing to do so is an ethical violation, once which deserves to be reported to their licensing board. BUT - my guess is that this provider isn't reporting them because he knows it's not true, that his patients are not scientifically exempt from the other 376,700 people in the world using PrEP without incidence. Preferably he is also reporting any adverse events to Gilead ( and Dr. Bob Grant ( The fact that he hasn't done so just confers that he is not being truthful.

(5) How do we know that PrEP is more than 99% effective at reducing risk if taken daily? Again - we have the stats I showed above in section (1) in which 12,301 people took PrEP under supervised conditions in efficacy trials with zero infections with actual use. Then we have 8478 more people in demonstration projects with zero seroconversions with verified use (, then we have 356,700 more people in the real world - only 3 of whom acquired HIV with verified use ( Three out of approximately 376,700 people is much higher than 99%!

If I were you, I would seek another provider. It's one thing for a doctor not to know things about PrEP. It's quite another to intentionally distribute unsubstantiated lies resulting in you and likely other consumers quit using PrEP. If you are in the U.S., I would consider letting the AMA know about what you have been told ( Outside the U.S. you may have to Google which licensing board they are accountable to.

I use the term "consumer" very consciously here, versus "patient." As a consumer of medical services you have a right to seek care from someone who practices based in science, not stigma. You have a right to receive medicine, not morality. I'd strongly encourage to consider ways to do that if you can.

To learn more about the science, facts, research, data, and real-world experiences of using PrEP, please feel free to join my Facebook "PrEP Facts" group at There you will see informed consumers as well as providers discussing facts that are based in data, not cruel dogma.

I hope this information will help you to make fact-based decisions about your health and pleasure. And thank you for bringing these errors to the attention of our readership. Take good care!

Non sexual Transmission concern- may seem crazy
Anal sex, HIV positive and PEP?

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