The 23rd International AIDS Conference (AIDS 2020) was held virtually for the very first time and featured discussion about the current direction and future prospects for HIV prevention, diagnosis, treatment, and even cure. During the official press conference on July 7, Ricardo Diaz, M.D., Ph.D., reviewed promising results of what might be the first adult with HIV to achieve long-term HIV remission without a bone-marrow transplant.
Diaz is an infectious disease–trained physician who conducts translational research in HIV/AIDS. He is a professor at the Infectious Disease Division and head of the Retrovirology Laboratory at Paulista School of Medicine, Federal University of São Paulo, Brazil. Diaz has over 150 articles published in peer-reviewed scientific journals. He is also a member of the Brazilian Consensus Guidelines for Antiretrovirals for Adults and Adolescents of the Brazilian Ministry of Health and acts as a consultant in the area of laboratory for the STI, AIDS, and Viral Hepatitis Department of the Brazilian Ministry of Health.
Diaz spoke with our correspondent, Terri Wilder, M.S.W., after the International AIDS Conference.
Terri Wilder: Dr. Diaz, can you start off by giving me an overview of the trial that was conducted?
Ricardo Diaz: We designed this trial a long time ago, 2012. And we started to recruit patients in 2014. At that time, we got the idea that we need to combine interventions in order to mitigate the number of HIV-infected cells of one person. So, this could solve two problems that we have with HIV infection, which is: the inflammation that goes on in spite of treatment; and the cure. Everybody thinks that if we reduce the number of the infected cells, we can get closer to the cure.
At that time, we thought that the barriers for that was the potency of the antiretrovirals that we currently use. There are some papers that say that 80% of patients on treatment still have a low-level viremia, with an average of 2.9 copies/mL. So if you are able to use a sensitive assay, you will still see viremia in those patients.
The other barrier would be the latency. So, we need to deal with latency.
We get 30 patients and we divide those patients into six groups; that’s five patients in each group. And we combined strategies. So, besides the control group, we intensified treatment for everybody. Everybody was under treatment, with viral load below detection limits for more than two years. Then we invited those people to get extra interventions that would be, in one group, just intensification with two drugs, dolutegravir plus maraviroc. That was the first time that dolutegravir was used as intensification therapy. And it was the first time that someone used two drugs for intensification. We also knew that maraviroc had an anti-latency property.
In the other group, we used the intensification plus nicotinamide. The other group, we used an intensification plus auranofin; it’s a gold salt that just kills infected cells. In the other arm, we used the intensification plus dendritic cell vaccine. In the other arm, we used everything. We didn’t use maraviroc in the vaccine arms. But in this group, Group 6, we used intensification with dolutegravir, nicotinamide, the gold salt auranofin, plus a dendritic cell vaccine; it’s a therapeutic vax.
What happened—it’s complicated. It’s kind of too many things. But we are trying to exploit which interventions could be good for the decrease of this compartment, which is the HIV DNA compartment in the cells.
It turns out that, in general, the arm that did better was the arm that we did everything. We got there, two post-treatment controllers. But when we interrupted treatment, those two post-treatment controllers got signs of the virus back. And although they were below detection limits, they got some virus in the cells. They were negative with the biopsies and the cells in the blood when we looked for HIV DNA by the end of the study. But after we interrupted [treatment], we saw that the virus was coming back. Then we would treat them again.
For our surprise, one patient from the group that got the intensification plus nicotinamide is still below detection limits. And he’s behaving in his immunity as the Berlin or the London patients, because he’s losing antibodies. He doesn’t have the cell immunity. And, pretty much, he’s behaving like those two patients. That’s the whole history. We think that we could show these results.
And of course we are going to follow up for more time, this patient, to see what’s going to happen.
TW: Did you say “gold salt”?
RD: Gold salt. It’s auranofin. The gold salt—it’s a heavy metal, of course—was used for rheumatoid arthritis in the past. We saw in animal models, a work by Andrea Savarino, that in animal models that used the gold salt, you are going to decrease the number of infected cells. Because this is going to kill those cells that harbor HIV. So, this worked in animal models.
And then we decided to do this in humans. So, the first time that this was done in humans. When I decided to do that, Andrea Savarino, that had done the work in animal models, just came to Brazil and said, “Oh, I want to be here to see it.”
He sat down and he said, “In Italy, nobody had the courage to do this. And you’re doing this. I want to participate.” So he’s coming sometimes with us, just to be part of the group.
TW: What is nicotinamide? I have never heard of it before.
RD: It’s a vitamin. It’s B3. It’s a vitamin. And so we, at that time, in 2012, we think that the first latency reversals were HDAC inhibitors. We saw deacetylase valproic acid; it’s an HDAC inhibitor.
So, the HDAC inhibitor; it’s like that. Chromatin is inside the cell. And there is an anchor there that’s the histone. Because we need to transcribe proteins, and the chromatin is not free; it’s just anchored by a molecule called the histone. Vorinostat is the name of the HDAC inhibitor which we use for some skin cancers.
Then when the histone deacetylase that is enzyme, the deacetylase, the histone, the chromatin is going to regrow, this molecule. And this is latency. In other words, if you inhibit this histone deacetylase you are going to prevent latency. And there is another enzyme that is a methyltransferase that makes a histone, the chromatin, just to be back again, and also revert latency.
Then, when we are studying, we saw that the nicotinamide was an HDAC inhibitor that was being described. We said, well, we have something here. That potential was not explored. But it does a thing: It can inhibit the histone deacetylase. So it can maybe reverse latency.
And we also saw that this drug can stimulate the methyltransferase by another mechanism, and can also stimulate the HIV protein, that stat, to restart the replication inside the cell. So now we know that probably we have three mechanisms from nicotinamide to wake up the virus, to interrupt latency, which is the HDAC inhibitor property, the methyltransferase stimulation, and also to prep that protein for the virus to start to replicate. Then we went to the bench, in the lab, and confirmed that.
We just published this not long ago, because we saw the need to publish this in order to convince people. But we saw back there that this drug was doing the job, on the bench. So, we get cells from patients that were HIV positive. They have been treated for a long time. Viral load was below detectable. So we got those cells. When we treat with nicotinamide, the virus just pops up, showing that we’re able to reverse latency in vitro.
Then we decide to use this in vivo. At that time, we saw some evidence. Now that evidence is confirmed. Another someone has studied that maraviroc was also reversing latency. And now we know that it does by a distinct mechanism, by stimulating the—everything has a name and a surname (that’s called biology). So, there is—it activates the NF kappa B in the cell. When it does this, it’s going to increase HIV replication. So, maraviroc also reverses latency.
It looks like right now that this combination is powerful to reverse latency; in vitro, when you combine it, this is powerful. And in this group of patients we saw signs in three out of five patients during the study of viremia. One was this patient. So, three out of five get signs of viremia. So, they are taking five antiretrovirals. They had no history of viremia before. And we saw this in their regular viral loads.
We still need to do more testing—that’s something called cell-associated RNA—to see if the virus is making proteins. OK? If you have the cell-associated RNA there. So, we are going to use this, too. But, actually, we don’t need [to]. We saw viremia in those patients. We got samples from those patients every four weeks for 48 weeks. So we had plenty of samples. And we have done viral loads every four weeks for those patients, during a 48-week period of this study. And we are able to see that.
So, that’s the history of nicotinamide. Nicotinamide has been used in the past for the cardiologists to treat high cholesterol. But now they do not do this anymore, any longer. It’s been an adjuvant for skin cancer, melanoma. There is some evidence in murine melanoma that when you treat the cell with nicotinamide you are going improve the CD4 and CD8 together with the tumor, showing that perhaps we are increasing the cell immunity with nicotinamide. And you are immune because we’re increasing CD4, as well. So, it has this thing with immunity, as well.
TW: What can you tell me about this patient that’s now being called the Brazil patient?
RD: Well, this patient—well, he’s probably different. Because we used this in five patients. And he’s the only one that got this result. We think we know why he got this result, but we don’t know why the others didn’t. So. He may be a little special.
He got HIV between 2010 and 2012, because he had a negative test in early 2010 and a positive test late 2012, in October. So it was somewhere in between.
But he had a full Western blot with seven bands. There is one band in the Western blot that’s the p31. The p31 is negative the first six months of infection. So he had more than six months of infection. But this is not a known infection. Because he was negative, a little bit more than two years ago.
When he first appeared, he was with a CD4 a little higher than 350, and a viral load of about 20,000 copies—not a very high viral load. And his CD4 was not a very high CD4, showing that he was progressing. Probably he was more a progressor than a controller, probably.
Then he started treatment. He started treatment at that time in Brazil, with AZT, 3TC, and efavirenz, in November 2012. Then soon, he changed to tenofovir, 3TC, and efavirenz. And his viral load was below detection limits.
Our inclusion criteria for this study was to have a viral load below detection limits for two years, because we’re checking for adherence, and also showing that we are not increasing the pool of HIV-infected cells. We paralyzed them. Also, a nadir of CD4 higher than 350. Because we wanted these patients—we didn’t want patients that have a very large pool of latent cells.
If you look at the RIVER trial or the trial from the NIH with vaccines, they always get patients in primary infections. We were not able to get patients in primary infections, but we wanted a nadir of CD4 higher than 350. So, he was like that.
And so, he was being followed in another place. I went to this other place, and then showed the project and said, “Well, if you can refer patients to me, you may.”
And this patient was referred from another site to me because he fulfilled all those characteristics. And when he started in the study, I was kind of worried. Because, as he had that blip of viremia, I thought he was not adherent. But he’s always saying that he was pretty much adherent. He came to all visits. Sometimes people, it’s one or another visit; but he came to all visits.
And then after we finished the study—that was 20 weeks—he just kept the regular treatment. So, in our study, patients came using antiretrovirals, three drugs. Then, on the top of this, we gave more. In these cases, we gave more, three drugs. But we finished in 48 weeks. We just took out the three extra drugs. And he was, again, back to his original treatment.
He was there for almost three years. That was when we decided to do the analytical treatment interruption (ATI). Because I was gathering some information to see how safe it was to do ATI in those patients, the analytical treatment interruption.
It turned out that it’s not very harmful. And, importantly, it’s the only way that we have so far to test if patients are going to be controllers, is to interrupt treatment. We don’t have an x-ray that is going to say there’s no virus in this body, or there is some virus in this place; we don’t have this.
So what to do? It’s to interrupt treatment. And we have done this for everybody—even for patients that are from the control group. The control group, they were there. And they were assigned just to do everything, but don’t take any extra drugs or interventions. They would get rectal biopsies, cells, blood, saliva, urine every month; but they didn’t get anything else.
And everybody agreed to interrupt treatment. Because, think about that—if you have a controller in the control group, this is a proof that this was not our intervention that’s doing good for the patient. So, we need to compare just something like that.
After we interrupted treatment; that was interesting. Because when we finished the 48 weeks, this patient had DNA of HIV in PBMCs [peripheral blood mononuclear cells] and in rectal biopsy. Two patients from the other Group 6 didn’t have; they declined and disappeared. But this patient had.
And when he came back, almost three years after, to do the ATI, we saw that the DNA in the PBMCs were negative. We didn’t find DNA there. So something happened in this between.
The titer of antibodies during the study was declined, to half. And then when he was in that interval between the treatment and the ATI, the titer of antibodies was still going down. And after the ATI, from 17 months to now, it’s still declined, which—something’s going on. He’s losing antibodies.
That’s the paradigm of infectious disease. If you don’t have any antibodies, you don’t have an antigen.
And also, we are doing now the ELISPOT to see the cellular immunity. But we have done, with 12 weeks of ATI, the ELISPOT of a number of patients from the other groups; and we included his sample. And he’s negative. All the other patients are positive. So what we have to do now is to prove that from the beginning he had some cellular immunity, and he might be losing [it] now.
But we have this little piece of evidence that he also does not have the cell immunity at that point. But we have got the results soon. We are doing this since yesterday.
TW: How old is he?
RD: He’s 35 now.
TW: Why do you think he enrolled in the trial? I know he was referred. But somebody had to talk to him about it. What was his motivation for being in the trial, do you think?
RD: I think that everybody’s motivation was the possibility of getting rid of the virus. This is so strong that even patients from the control group agreed to be in the control group, because they knew that if you have holdover, they would be there. I think that was the motivation. It was not hard to recruit those patients.
And now he’s extremely happy, because he’s—you know what? When he was with the old viral load below detection limits, he went by himself to the testing center, in the Brazilian anonymous testing center. And he had the rapid test. And it came negative. And he sent me the pictures. He wrote, “It’s negative. And now what?”
I said, “Well, this test is not sensitive enough. It means that you have low titer of antibody. Just this.” We didn’t have the results of the titer of antibodies. But I said, “Well.”
So, that’s his motivation. He went by himself to be tested. And I know he’s happy.
TW: Was there anything else unique about him? I mean, I’m just kind of curious about his health history, in general. Did he have any other comorbidities? Did his parents have good health? I mean, was there anything about his history that is particularly unique that you can think of that might explain this?
RD: Yeah. We’re looking. But we can’t find. We know that he is CCR5 wild type. We are doing HLA now to see if he has any HLA profile that is going to prevent progression. But, not. He progressed. He was kind of low CD4. And he has something—he may have something—special. But we don’t know why he is behaving like that. And we don’t know what this is.
But nothing. We keep talking to him. There is nothing different.
TW: How long do you think it will be before you can truly determine that he’s, quote, cured?
RD: If you look at the Berlin patient, he’s losing the Western blot bands. So that’s something that is telling me not about the quantity of the antibodies, but the quality of the antibodies. So, this was going to be a good evidence for me.
Right now, he has all the bands of the Western blot. If I look carefully—I need to be devil’s advocate—but if I look carefully, perhaps the GP120 is a little less intense. It’s faded. But I’m not sure about that.
So, I think that the quantity of antibodies is declining. We need to see if the quality is going to change. So, if he starts to lose some Western blot bands, this would be something that is more indicative to me. But, no. He’s controlled infection, not very impressive.
TW: So, how long do you think you’re going to follow up?
RD: We didn’t find HIV DNA in the cells. Not very impressive. His declining antibodies—this is impressive to me. The cell immunity is going away. This is impressive to me. If he loses the Western blot bands, then I’ll say, well; maybe that’s it.
TW: So what’s your plan? How long do you anticipate following him?
RD: Forever. But, you know, the Mississippi baby caught viremia almost five years after.
Those two patients that had the bone-marrow transplant in Boston, the Boston patients? It takes longer. One, three months; and the other, six months. Well, he’s 17 months. It’s longer than the Boston patients. But we know that if you decline that reservoir the virus may come back.
It’s like throwing dice, OK? How many times do you need to throw to get the number 6? When you get the number 6, the infection is going to pop up again. If you have 10 dice, your chances are higher than if you have only one. So, maybe he has still dice; and it’s only one. We need to wait a little more.
TW: So what’s next? Are you going to do a larger trial? What’s next for you in terms of the research?
RD: We now have funds to do a larger trial with 60 patients, with the strategy that we think works better. And that includes the cessation of maraviroc and nicotinamide, based on his case, the intensification, based on his case, as well; and the gold salt plus the vaccine, based on the other group, Group 6, that had statistical significant decay in the DNA in two patients where there was very low DNA, that we’re not able even to find DNA.
So we are going to go with this design. As I mentioned to you, this group that had the best results did not have maraviroc. That would be a better outcome, to have maraviroc, as well.
So we are going to recruit 60 patients. What we are going to do—those patients that are still being followed with this study, we are going to offer them to redo everything with something that we think is going to work better. Then we are going to recruit the extra patients, just to see. That would be interesting, because we are going to see on top of the old treatment, if the new strategy is going to do better or worse. And we can compare with people that never interrupted treatment, for instance.
TW: Great. I think this is amazing. And fingers crossed that it continues to be successful. I love that you describe him as being very happy right now.
TW: And I’ve seen often that Timothy Brown says it’s very lonely to be part of this group, and that they want more people to be part of it.
RD: That group [is the group] of people no longer living with HIV.