Scientist Stories: Anna Greka, From Genes to Mechanisms to Medicines

A very good evening, everyone. My name is Namrata Sengupta, and I'm a science communications officer here at the Broad Institute of MIT and Harvard. It is my pleasure to welcome all of you in the room and all our online audience who are watching from YouTube. This is the fourth talk of the Broad@15 series. So welcome. The Broad Institute came into being in the year 2004. Since then, we've witnessed revolutionary changes in the fields of both biology and medicine. These talks The Public Talks of Broad@15 series will celebrate the amazing pace of scientific progress over the last 15 years and the parts we at Broad have played in it. It is my honor to introduce tonight our speakers, two very inspiring women in science who several young scientists in the room and all over Broad look up to, Dr. Flo Wagner and Dr. Anna Greka. Flo Wagner is an Institute scientist here at the Broad. She's the Director of Chemistry at the Center for Development of Therapeutics and the Stranley Center for Psychiatric Research. Anna Greka is an Institute member at the Broad, where she directs the Institute's Kidney Disease Initiative. Anna is also an Associate Professor at Harvard Medical School and an Associate Physician at Brigham and Women's Hospital. Together, Anna and Flo will talk about the journey of drug discovery, reflecting on the past, present, and the future. They will also share some interesting stories about how scientists are translating genetic insights into much-needed therapies, and how biologists and chemists are collaborating to develop treatments for patients. If you have questions at the end of the session for Ana or Flo, please raise your hand and our mic runners will come to you with the mics. Or you could text your questions with the number displayed on the screen. If you're watching online on YouTube, you can ask your questions with YouTube's chat feature. If you're tweeting, please use the hashtag #Brodit15. If you're posting about our event on social media, Tag Broad Institute so we can reshare your posts. And without further ado, Flo Wagner and Anna Greka.

So thank you very much for sharing part of your afternoon with us, or evening with us today. And Anna and I are really excited to take you on a journey for small molecule drug discovery. And with the help of our drug huntress, Diana, we're gonna reflect on the past, present, and future of drug discovery. This is a journey that takes between 10 and 20 years from understanding a disease at the molecular level, finding a molecule and optimizing a molecule that can then be tested in disease-relevant models, such as animal models, potentially getting into the clinic, and then hopefully reaching the patients. But before we start on our journey, I would like to talk a little bit about the definition of what is a drug, what is a medicine. So when I think about drugs and medicine, typically I'm thinking about our local pharmacy and those long shelves full of bottles and, and boxes. And there's actually over 1,500 drugs that have been approved by the FDA currently. When I think about this number, I think, huh, that's a lot of different drugs. But then when I think a little bit further, there's so many diseases that humans are afflicted with, it's actually not that many drugs to treat all the disease. And so I think we have a lot of work ahead of us, and we really have our cutouts cut out for us. So what is a drug? Well, a drug is a chemical agent represented by those little pills here that interacts with a biological target represented by this drug target right here. And it changes this biological target. There's different therapeutic modalities. Four of the main ones are small molecule, Those are the typical drugs such as aspirin, for instance, that we tend to use or all of us have used in the past. Antibodies and the most recent gene therapy as well as cell therapy. There's more, but the focus of our talk today is going to be purely on small molecule. So in this context, the small molecule is represented here by this blue molecule here. And our target, our drug target, is the protein here in gray. And so if you think about it, a concept that has been used in the past and introduced by Emil Fischer, it's a somewhat flawed concept, but it's still very accurate, I think. You can think about the drug as the key and the drug target as the lock. And the way that it works is that the key turns on or off, the molecule turns on or off, on or off the biological target or the protein of interest. So with that in mind, our ancestors were all drug hunters. By, through blind experimentation, they would chew or eat or apply roots and plants and different organisms to help their suffering and cure their disease. Of course, most of the time it actually didn't work. But through trial and error, a number of medicines have actually been discovered, and I'm going to give you a couple examples. So the berries of juniper have been used in traditional medicine to treat diabetes because it's lowering blood sugar. It's also been used to fight kidney and urinary tract infections. Poppy, so opium, has been used. It contains morphine. It's been used as a painkiller, so it's fairly well known. And of course alcohol is a psychoactive that hopefully most of us are using responsibly to decrease our inhibition and increase our sociability. So as our drug huntress Diana became more scientifically informed, serendipity still played a major role in drug discovery. And so I want to give you the example here of the discovery of penicillin in 1928. And so the story goes that Sir Alexander Fleming went into his lab basement in the St. Mary's Hospital of London, and what he saw there was this Petri dish Oops. This petri dish right here that contained a bacteria. And the bacteria was not growing because of a blue-greenish mold around it. The petri dish had been left open, and so the mold was able to enter the petri dish. And so using his observation and intuition, he was actually able to purify this mold and eventually found penicillin, which is the molecule that you see here and represented in 3D here. And so that was an incredible breakthrough in the treatment of influenza, and it really emptied hospitals at the time. The interesting fact about Sir Alexander Fleming is he was a poor communicator and a poor orator. So despite publishing his discovery, None of the scientists at the time were actually interested in this discovery, and it took actually many, many years before penicillin was used in the clinic to treat patients. And so one must wonder if Sir Fleming had YouTube or Twitter, you know, if his discovery would have been entering the clinic much faster. So another Scot, Sir James Black, was a physician and a base— a basic scientist, and he called himself a pharmacological toolmaker. So he is really, he was one of the pioneers of pharmacology. So pharmacology is the study of a living, the interaction between a living organism and a reagent, a chemical agent that changes either its normal function or its abnormal function. And so thanks to him and others, of course, we were starting to really build molecules rationally rather than taking a bunch of molecules and testing them and see, oh, What is it gonna do? And so Sir Black became really interested in the effect of adrenaline on the heart when he was at the University of Glasgow. And he postulated that maybe a small molecule would be able to completely counteract the effect of adrenaline. And his invention eventually led to the discovery of this drug, propranolol. And so if you look at the structure here of adrenaline, you see in red the similarity between those two molecules. Eventually, the development of this drug became a best-selling drug for the treatment of heart disease, and it was really a breakthrough treatment since the 1800s with the discovery of digitalis. So it was really groundbreaking, and it got him a Nobel Prize. For this discovery. So, now we are in the 20th century and pharmacology is definitely used a lot to design and optimize compound after a very particular target. And across the channel, there's a French surgeon named Henri Laborit that postulated that promethazine, this molecule right here, was actually stabilizing the central nervous system. And so he reached out to a French company called Rhône-Poulenc, and there, there was a very talented chemist, Paul Charpentier, using pharmacology that decided to design a few analogs, a few compounds that look very similar to promethazine, And one of them was chlorpromazine. And chlorpromazine was actually approved for use as an anesthetic booster for, you know, during surgeries.

But that—

so that's the pharmacology piece of it. But Henri Laborit didn't want to stop there, and he thought, well, I wonder if I could use this drug in psychiatric patients, in psychiatric wards. And so this is where the serendipity comes in a little bit. The story goes that Henri Labourit and one of his colleagues actually injected in another colleague, Cornelia Corti, chlorpromazine. So this is kind of a cowboyish experiment that certainly we wouldn't do here at the Broad or anymore. Well, while she noticed that there was a feeling of indifference, when she stood up, she actually passed out and fell to the ground. So it was kind of a failed clinical trial at the time. And the reason why she passed out is because of hypotension, which is a known side effect of this molecule called chlorpromazine. Well, despite this failed experiment, Henri Laborit continued to test this this particular molecule in psychiatric wards. I eventually ended up treating a 24-year-old manic patient who, after only 3 weeks of treatment, was actually released from the hospital. So now you have to understand that at the time when you had a manic episode, you usually would go into the hospital and not leave the psychiatric ward. And so the same way that penicillin actually emptied hospitals of people suffering from influenza, chlorpromazine really emptied those psychiatric wards and really changed the lives of many patients. But you had to be a little bit cowboyish about it to discover this. So now we are towards the end of the 20th century. And, you know, I've told you those 3 stories, and typically those discoveries were made by one man or a small team of scientists. And those discoveries, of course, were low throughput. They didn't happen fast enough. And so now, at this stage, drug discovery became a team sport, and really a lot of people across different disciplines were working on drug discovery at different phases. And so this model, this process of drug discovery really hasn't changed since the end of the 20th century. So you pick a disease, you pick a target, you're gonna test many, many compounds against that particular target or model. And then you're going to try to optimize a few of them to potentially enter the clinic if they're safe enough. In Phase 1, you're really determining if the compound is safe. In Phase 2, you determine its efficacy. And in Phase 3, you determine the therapeutic effect of the drug with the hope that at least one of them will be approved by the FDA and reach the patients. So this is our lab on the third floor. This is our high-throughput screen facility here. I reassure you, our scientists don't work this fast, but there's been a lot of automation that has happened over the years so that instead of testing one compound at a time— and, you know, if we do this, my great-great-great-great-greatchildren would probably see the effort that we we work on and finally a cure for something. Here we're able to test thousands and thousands of compounds in, you know, a few months and really test if those compounds actually modulate the particular biological target. And so the analogy that we use is testing those thousands and thousands of compounds, we're really looking for the needle in the haystack. And now we can do this more efficiently. More efficiently. And a lot of the drugs that have been approved at the time, about 50% of them, were actually discovered through high-throughput screens. So it's been a very efficient process. Okay, so now I have the needle. Well, that doesn't mean I have a drug. So I found a molecule that does something to a biological system, but I have to make this molecule drug-like, so safe, potent enough and efficacious, of course. And so the medicinal chemist like myself will use rational design in a structure-activity relationship. And so what that means is that we're looking at the structure of a molecule. So this is Celebrex. This is a painkiller. And, you know, the structure in itself, it really doesn't matter. But what the medicinal chemist does is that we cut this molecule in smaller pieces and we're gonna change each of those positions We're going to change them a little bit. And the reason why we do this is we want to improve the different properties that we're juggling with. So we're going to improve, for instance, potency so that you don't have to take, you know, a horse pill. So you take a smaller pill. We're going to try to improve the stability so that the compound stays in your body once it's entering your body, that it stays in there and it's not metabolized. Or we're going to try to increase the selectivity so there's not that many side effects. So there's a lot of things that we're juggling with to finally get a compound that is more drug-like. At the same time, we are looking at improving the drug exposure and safety. So I'll go a little bit in that. So one of the concepts is ADME. ADME stands for absorption, distribution, metabolism, and excretion. Excretion. So absorption, if I take a pill, will actually get in or will it be excreted right away? Distribution, if let's say I'm trying to treat a headache, will it get to the brain or will it actually not get to the brain? So we need to reach the organ of interest. Will it remain intact, right? So every time that we take, that we put something in our body, the body thinks, This is something strange. This is strange body that I need to get rid of. So the body will just chop it up in more polar pieces that can be easily excreted. So will it remain intact long enough for me to see an effect on the disease? And then finally, excretion, how fast am I going to release the compound from my body? So how long is it going to stay here? Toxicity, we're always balancing benefits and side effects. So I'm sure all of you have seen those commercials on TV where they say, well, I'm gonna treat your headache, but your knees are gonna hurt and you're gonna vomit, right? And so those are the side effects. What are the benefits compared to the side effects? If the benefits outweigh the side effects, then potentially we have a drug. No drug is a clean a clean drug. None. And what we use in drug discovery, we use a lot of preclinical models such as animal model to minimize the risk in humans. So now we have new challenges with all those new in vitro, in silico models that have been created at the end of the 20th century and beginning of the 21st century. Now we have a really successful with drugs that enter Phase 1. So remember Phase 1 is where we determine safety of the compound. So in Phase 1, now we have a high rate of success, about 64%. And so that's great. We're able to create molecules that are really safe. But then we see the attrition moving to Phase 2 and Phase 3. And this is where we measure efficacy. So why are those drugs that are safe, that we know are going to the target, why are they not efficacious? And so you see in phase 3, typically drugs lack— fail because of efficacy, not because of safety. And so, well, this is what we have right now, and this is a new challenge, and a lot of people are working on new technology to improve improve this. So we want to test the activity of those lead compounds in different disease-relevant models. And those disease-relevant models become more and more complex and more relevant to the disease. So we usually start with a purified protein here, then we go into a cell, and then we go into animal model. The problem is none of those models are actually humans. And so a lot of very smart scientists are working on improving this liability or this challenge. And so companies suffering from this attrition inefficacy have taken different routes to try to improve their pipeline. They acquire other drug pipeline from other companies. They collaborate with academia, with companies such as— or institutes such is just abroad. But also, the revolution in genetics has been key. And Anna is going to talk about this.

So it's a pleasure to be with you today. Let's talk about genetics. How might genetics have helped us in developing new treatments for patients? How might they help us in the future? Well, we're standing in one of the world's preeminent genetics institutions, of course. And so it goes without saying that this is an area of great interest for us. So for those of us who may not be experts in genetics, I thought it would be good to take a crash course for a moment. Our DNA is basically comprised of a series of letters, actually 3 billion letters on each of our strands of DNA in each of our cells for all of us. And it's basically a series of letters that spell certain things that mean certain things to cells. We will get into that in a moment. More about that in a moment. But as you can see, the correct spelling in most cases has to spell something that makes sense for the cell. So in this case, for example, C-A-T or cat. But if there's a mutation or an error in the alphabet in the DNA, then you end up with a misspelling. For example, tat, which obviously means something different, right? So then DNA makes proteins. Proteins generally, along with some other things, make cells. Cells make our organs. If there's a defect in the DNA, you can see how this becomes a cascading event that ultimately leads to something going wrong in that organ, which is really how disease begins. And so of course, the fact that genetics has been contributing to disease has been known for a long time. For example, this is a picture from the medieval times when people knew that there were certain families in which, families in which members would over time develop this horrible chorea, as it was called, or dance. Chorea is the Greek word for dance. And it was just a very dance-like motion of people who developed this neurologic disorder. Of course, now we know that to be Huntington disease, and then they would ultimately pass away. And so it was known for a very long time that this was something that ran in families, but of course we didn't really know the actual cause of this until the discovery of the gene, which actually happens to be be the first gene to ever be identified as the underlying cause of a human disease. And in fact, this is what we call a monogenic human disease, so a disease that is caused by a defect in a singular, one gene in our genome. So it was eventually identified in 1983. It was, of course, confirmed to run in families and lead to death in early to mid-adulthood. And the treatments, think about, it was discovered in 1983. Of 2003 are just about now coming on the horizon. But of course it was known since many, many hundreds of years ago, and now finally with the advent of genetics, you can see how this now can become a reality. It can also make the point that it's rather slow, right? From the discovery of a gene all the way to a therapy, it's not so straightforward. It requires a lot of work and a lot of people working in this team sport that we do here, chemists and biologists and doctors working together. The second gene that was discovered ever was the gene for cystic fibrosis, identified in 1989. And of course, if you're following the news, you will know that just a couple of weeks ago we had this amazing FDA approval for a series of drugs that are actually extremely successful in treating this disease. For those who may not know, cystic fibrosis is an inherited disease that is life-altering and life-threatening for patients. It affects the lungs in young people as well as young adults. As well as the digestive system. And of course, the most amazing victory is that we now have a series of drugs that can basically treat most cases of cystic fibrosis. This is again a tremendous triumph of modern medicine and modern drug making based on a genetic discovery. There are about 8,000 rare diseases that are caused by defects in one singular gene in our genome. So we have a long way to go. By now, at this point, we have found the cause for about 4,000 of these 8,000 rare diseases. So we have a lot of work to do both in genetics but also in, in the process of identifying the next steps in developing treatments. So of course one could go gene by gene as was done in these cases, or one could look for a more systematic way to decipher all the genes in the human genome, create the roadmap that would ultimately allow us to build drugs for patients for all disease. And so of course, as you probably know, especially those of you who may have been here for our founding director's talk, Eric Lander, that of course the Broad had a major role to play in this. The Broad was a major site for the Human Genome Project. It was of course a 13-year process that resulted in basically us understanding all 3 billion base pairs that comprise the human genome. And we learned from that process that there are about 20,000 genes that are encoded by all— 20,000 proteins, rather, that are encoded by all these genes in our genome. So this was a long process. It was very ambitious. It cost a lot of money. Some people back then didn't see the point of doing this. But of course, there was a major point. And the point is, now we had a systematic way of looking at the entire human genome and being able to look for defects that may cause disease. And so now what? Now that we have this roadmap, what can we do with it? Well, this is the process or the topic of our talk today, from genes to ultimately mechanisms and ultimately to medicine. So we ask, what genes underlie and cause a particular disease? In some cases, as we are mostly discussing today, it would be defects in a singular gene. That's already a pretty hard task because then You have to go from the gene to what goes wrong in which cell, and ultimately can we find the right drug for the right patient at the right time. But there's also, of course, many other diseases, complex diseases that are caused by many genes working together. And right now in this institute, we are working really hard to try to find ways to find the meaning of all of those genetic mutations and how they ultimately lead to disease. That's gonna be a lot harder. In the process of monogenic diseases, though, we have had some significant success. And Flo and I would like to share with you a broad story, a story that starts from a gene that was discovered here and is going all the way to a possible therapy which we hope to bring to our patients. And this is a story of a rare kidney disease called mucin-1 kidney disease. It is a rare inherited disorder. It's something we call an autosomal dominant disorder, which means it passes from from one generation to the next without fail. The mutation was discovered here at the Broad, and the reason that it was so hard to find it is because it's really a mutation that is hiding in the darkest corner of the human genome, in something called the variable tandem repeat region of this mucin-1 gene. And it took the entire firepower of the genetics folks here at the Broad, including Eric Lander and Mark Daly, who really brought a whole team of people together to try to find this mutation. Mutation, and ultimately they found it hiding in this very dark little corner of the human genome, as I mentioned, in the mucin-1 gene. I should say that the general area of the human genome in which the mutation was thought to be was known for 20 years, and so it really did take a lot of firepower and effort to get there. But now that we knew the mutation for this rare disease, we had so much more work to do. We had to understand what goes wrong in the kidney cells that causes kidney disease., and we of course were hoping to find a treatment to fix the problem. Before I tell you more about how we went about this, I wanted to share a story, a story of a specific family who have given me permission to tell you their family story about how they have been dealing with this disease. And it's really a story of 4 generations. It goes back to Rasmus Nielsen, back in 1849. He lived for 39 years and died from inexplicable reasons. As a relatively young man at the time. He had 3 children, Anna, John, and Andrew, who all died in their 30s, also for unknown, inexplicable reasons. Andrew Nelson had a son. His name was Roscoe Nelson. He was a surgeon. He served in the Second World War. He died at the age of 43. He knew, as he was a doctor, that he had kidney failure, but he didn't know the cause. The gene was not known. No one knew anything about this. He didn't know anything about his ancestors and what diseases may have afflicted them. Roscoe had a son, Richard Nelson, and he's the person who gave me permission to share their story. Richard actually developed kidney failure as a young man but was very lucky with the advent of modern medicine to receive the gift of life, a kidney transplant that has allowed him to live, and he's had a successful kidney transplant for the last 20 years. For 28 years. Well, the Nelson family now has made it their mission to partner with us to try to find the answers. And they were, of course, delighted that we had identified finally the gene that affects their family. And do you know why this is really important to them? This picture says it all. These are the siblings of Richard, who is here in the middle. His sister unfortunately passed away earlier this year from kidney failure. And these are the other siblings who have also been affected. These are their children who stand to be affected, and these are the grandchildren in this family who stand to be affected by this disease. So when you're faced with this, this is the enemy for this family. Of course, they want to partner with anybody who might be able to help them solve this fundamental disease in their family that has been really affecting every generation. So of course, the task at hand was we had the knowledge of the mutation, We wanted to know what goes wrong in kidney cells. What is it that affects the kidney cells and leads to ultimately kidney failure? That was the job. We took this task on. This is some work that we have recently done, and this is work that was done by a talented young scientist in the laboratory, Morand Vella. She asked, can I make a mouse model that looks like the humans, that can be used as a way for us to study to study this human disease. And so what you see at the top is actually what the human kidney looks like. You appreciate these holes in the patient biopsy of a kidney. This is a slice of a kidney that has been stained so we can look at that. And then you can see that when you look at the mouse model that carries— we took out the mouse gene and replaced it with the human mutant gene. You can see that the mouse develops the same kind of disease, these holes in the kidney that obviously don't belong there. This was good. Not good for the mouse, but it was good for our research that we could actually develop a mouse model in which we could study the disease. And so we went on to try to figure out what's going on with these holes in the kidney. And what we found is that the mutation is causing the accumulation of a toxic protein precisely where the holes are created, suggesting that this protein, this toxic protein, had something to do with how these holes in the kidney were formed. So with additional work, we were also able to find this true in cells. We were able to get cells from a patient with this disease, kidney cells that we were able to grow in the petri dish, and confirm the idea that there was indeed a toxic protein, as shown in green, that accumulates where it doesn't belong inside these kidney cells and ultimately kills them. So we had now a mouse model and also a cell line. That allowed us to understand how the disease happens, what the mechanism of this disease is. Remember the second box in our arc of discovery? So we knew that there was a mutant gene. We knew that there's a toxic protein that accumulates in kidney cells. We knew that the cells die as a result of this toxic protein. And this is what causes the holes in the kidney and leads to kidney failure. And so what I'm describing in just a singular slide is actually the work that took all— took many years to complete. But this understanding actually now gave us a way to ask the very important question, can we find a drug, a small molecule that will make this mutant protein go away? Can we clear this mutant protein away from the kidney cells? Well, I am a doctor and a biologist, but I absolutely needed the work of a chemist in order to develop the tools and resources that are needed to answer that question. So Flo will tell you what happened next.

Thank you.

So we needed to bridge that gap between understanding the disease at a molecular level, having actually those models, and we needed to find the molecule that was going to eventually change and rescue this particular disease. And so working here at the Broad Institute, with world-class investigators such as Anna and also other investigators that create really transformative novel technology. We're using all of those within the Center for the Development of Therapeutics to try to bridge the gap to find molecules that can then be tested in the clinic and potentially reach patients. And so there are a lot of technologies that have been developed for the in the past 15 years, and there's no way for me to address all of them. We don't have enough time for this. But I'll focus on one that is particularly relevant to Mukwon disease, and that is repurposing. So this is a picture of our fridge upstairs that contains close to 1 million different small molecules. And so we could test all of those molecules against the particular model that Anna has created. But what we decided to do is we're gonna first look into a smaller AStack that is called the drug repurposing hub. So what I told you earlier is that most drugs that enter the clinic do not fail because of safety. They're totally safe. They just fail because of efficacy. So what if we could use those drugs that are shown and have been shown to be safe safe, and we can actually repurpose them for a different indication. And so there's a collection that's been put together by Stephen Corsello and Todd Golub of about 6,000 compounds that have been either in the clinic or that have been optimized for a particular target. And so this was the particular model that Anna has created was tested against the drug repurposing library. But first, what are the prior examples of drug repurposing success?

What does—

what do you mean by repurposing? So I'll give you 3 examples. The first one is aspirin. The old indication is pain. Well, now it's actually used for coronary artery disease as well. Sildenafil, also better known as Viagra, was actually first developed as a hypertension drug. But during the clinical trial, they noticed very interesting side effects, and now this is used for erectile dysfunction. And finally, the last one, thalidomide, has a terrible, terrible history. Some of you might remember that this was used to treat pregnant women for morning sickness, and unfortunately, babies born from those mothers had really severe deformation. So it was removed from the market, obviously. But just recently, it was discovered that it could be used to treat multiple myeloma. So really transformative reuse of this compound that had a tragic side effect. So we ended up screening those thousands of compounds from the drug repurposing library and collecting thousands of images against the model that is here. So remember, the toxic protein here is in green. And so in this patient cell with the toxic protein in green, we added that one molecule, and as you see, the green is gone. And the good protein that is necessary to fight infection is still there, and that was key.

Anna? Okay. So the chemists So this helped us develop an assay, and we found a drug that had some promise. It's amazing, right, what you can do in cells. But the real question is, could it do anything beyond getting rid of the mutant protein in the cells? So we, of course, asked that question. Can we do anything about the mouse? And so here, of course, is the evidence in the mouse that actually this compound, this drug-like molecule, had some promise.. So as you can see here, here's a mouse that has the mutant toxic protein massively accumulating in their kidney. This is a sibling of this mouse that received the drug for one week, and this is a control mouse, a mouse that does not have the disease, as a comparator. And I'm sure you would agree with me, even from the back of the room there, that you can see that the mouse that received the drug looks much more similar to the mouse that does not have the disease. So we really were able to bring down the amount of toxic protein that accumulates in the kidneys of these mice. This was really good. But of course, I aspire to be a person doctor, not a mouse doctor, although it's nice to have this evidence in mice. And so we asked the question, is there any way without doing a clinical trial, because we were not anywhere near that yet, remember we have to establish safety, is there any way that we can get some confidence in the idea that this could actually work in humans? And so this is where this new technology comes in, technology that we also are building here at Brown, and that's mini kidneys in a dish, otherwise known as, properly known as human kidney organoids. This is an example of such a system. As you can see, it's a, you know, kind of round structure that actually contains, as is shown in these different colors, all the fundamental components of what a human kidney would be like. It contains the filtering units in red, and in cyan and green, the tubular compartments of the kidney. You may have to take my word for it, but to say that this is actually a system that is now a human mini kidney. And it looks something like this. If you look at a dime, it's about this size. This is the size of your kidney in your body. So it's actually not a real kidney, but is an excellent model system in which to test compounds and ask the question, is it possible that this drug-like molecule can work in the human kidney system? And so we, of course, asked that question, or I wouldn't be telling you. And this is what we found. So these are 3 patients. These are the tubules, the specific cells in their kidney organoids that are accumulating a lot of this toxic protein. This is one of the siblings, the brothers or sisters of these patients who do not carry the mutation. Mutation, do not have the disease. Just to back up for a moment and tell you how these patients were able to partner with us to build this model, it involved them coming in, consenting to do this, giving us a vial of blood. We took cells out of their blood that are called erythroblasts. We took those cells and turned them into pluripotent stem cells. And then we took those pluripotent stem cells and turned them into these kidney organoids. That's how this process worked. And these patients were able to donate their blood for us to be able to build this system and be able to test the efficacy, how well our drug is working in this system. So as you can see, it worked pretty well. After 3 days of treatment, these are, remember, mini kidneys in a dish. We applied the drug in the dish, and we could see that in 3 days, the mutant green protein had disappeared from these human kidney organoids. This is as close as we can get to getting evidence for the fact that One day when we build a drug that looks something like this one that we just discovered, we might be able to remove the toxic protein from patients' kidneys as well, which is of course our goal. So with this understanding and a lot of other work that I'm summarizing very rapidly here, we of course had the most fundamental question, which is how can we now take these discoveries, all the work that is going on upstairs, and actually bring them to the clinic? What is the ingredient or the component that is needed for us to be able to make that translation happen beyond all the equipment and all the scientists and all the teams of experts that we have here? And of course, the answer is our patients. All of you potentially, or all the people out there who partner with us to solve these clinical conundrums and problems. This is just to highlight that the Broad in recent years has been part of a revolution. And that's the revolution of going directly to patients and asking them, do you wanna be involved in our research? Do you wanna donate your time, your samples, your family's history, your stories, your tissue? Anything that might help us to accelerate our research. And the answer has been a resounding yes. And there are several projects that have been launched here, some of them in cancer, the Count Me In initiative, which some of you may have heard. And there's also another direct-to-patient project that I have been involved in. This is the Rare Genomes Project. This is not just for rare kidney disease. It's for all rare disease. It's for any person out there who has a family member who themselves suffer from a disease they cannot explain, they do not have an answer for. And we can offer to test them and find out if they have a genetic mutation that may be a driver for their disease. So we call this the Rare Genomes Project, and what I say is that it's the complete democratization of having access to a world-class institution like this where we do genomic research, it can hope to solve such puzzles. It involves having internet and a mailbox, and anyone can participate in any corner of this country in this project. And indeed they have participated. This is a map of all the people who have signed up for the Rare Genomes Project to date. And as you can see, every— almost every state is represented, and there are many, many people who are saying, yes, count me in, I want answers to my questions, and I wanna participate in this research. And it's a numbers game. The more patients we're able to recruit into this project, the more we will be able to decipher and solve puzzles, genetic puzzles. And so this is just the beginning, scratching the surface of this project, but we hope to continue to push on this and, of course, work on rare kidney diseases, but several other rare diseases that are out there. Remember I told you there are 8,000 of them. And we may have an answer to about 4,000 of them. So we have a long way to go. So with this in mind, what did we do for this rare kidney disease? Well, of course we partnered with patients, right? And so as I told you earlier, back in the 1990s, we truly had just a handful of families who were known to have this disease and who were known to have a mutation that carries this disease, but the mutation was not known. In 2013, Mark Daly, Eric Lander, and several others here discovered the cause of this disease, and since then we built a diagnostic test which which we make widely available to anyone, anyone in the world who wants to be tested for this disease, usually in partnership with a clinician who suspects that they may have this disease. And this allowed us to launch a registry together with valuable clinicians who are part of our team, both at the University of Cyprus where there turns out to be a founder effect on that island, meaning there were a lot of people who were marrying each other in a small area and so the gene had a higher chance of being, propagating in that patient population, as well as other doctors all around the world. And the idea was, now that we have more patients, now we can understand much more about the disease. We can understand when most people tend to develop kidney failure and what might be a marker, something that can tell us that they are developing kidney failure earlier, before their kidneys fail. This is the work that builds toward developing a biomarker for this disease. To the disease, which is almost as important as developing a drug. We need to have a way to know and read the effect of a possible drug on the disease, on making hopefully the kidneys better. So we have launched a clinical trial to exactly find the biomarker that might help us solve this disease. And of course, I'm proud to say that even though we started with a handful of patients, since the discovery of the mutation, largely because of the contributions of the Broad, we now have a registry that has 1,487 patients in it for an ultra-rare disease in the short 3 years that we've been doing this. This is an amazing victory. And we, of course, hope to build more and recruit more patients into the registry. But of course, as with the most amazing things in science, this has been the greatest privilege of my career as a scientist so far, is that when you make a discovery, it usually is, as is in this case, the case just the tip of the iceberg. And what I mean by this is we discovered a drug-like compound that removes a toxic protein from a kidney cell and hopefully can help those patients with this rare kidney disease. However, there are several other diseases that are caused by toxic proteins that accumulate in different cell types, and of course, naturally, we wanted to know, does our drug work, our drug-like compound work in any of those?. And indeed we have some early evidence that there's a common form of blindness called retinitis pigmentosa where our drug may have an effect. And we are very interested in testing this in several other diseases which collectively we understand and call them toxic proteinopathies. Some of them affect the brain and of course we're very keen on trying to understand all of those diseases. So again, the great privilege of being able to do science is that you can ask all these questions and and going to places where you never thought you would be and you never thought were possible. It's really one of the most amazing things about the work that we do here. So our discovery is only the tip of the iceberg, but we of course have so much more work to do before we can bring even this one therapy for this one disease to the clinic. Bridging this gap, starting from Diana and following the path of drug discovery all the way to actually coming into the clinic. We have a lot of work to do to follow exactly this path that we described for all those other diseases out there, both the monogenic, the ones caused by a singular gene, as well as the more complex diseases caused by many defects in several genes working together to cause a disease. There's a lot of work our colleagues are doing in this building exactly building toward that future. And of course we all aspire that there will be a time when we can actually develop treatments for all human diseases. Human disease. And so with that, Flo and I wanted to leave you with a final reflection. Women in biomedicine. We are very, very keen on the fact that of course there are two women here, two women scientists talking about the work that we've been doing here. Just a few years ago, just based on the pictures you saw from the history of drug discovery, there weren't many women doing that work. So we're very proud of course to be doing this.. And we're very astutely, keenly aware of the role that we play as role models for the next generation.

So, Flo? Yeah, so the data that you're seeing on this slide show that there is significant progress but still not yet parity. So while 61% of the students in undergraduate degrees, scientific undergraduate degrees, are women, when it's time to go to graduate studies and in the biochemical or the life science field, only 48% of women represent the students. 39% only become faculty in a 4-year institution, and only 21% of them actually full professor. And so we really hope that through this talk we are inspiring other women or other girls in high school to go into the field of science, stay in the field of science, and lead wonderful projects such as the one that Anna has been leading here at the Broad. So, thank you very much for your attention, and we'd be happy to answer any questions.

Thank you. Thank you, Anna and Flo, for the brilliant talk. For the audience, the floor is now open for questions. If you have a question, please raise your hand. Our mic runners on both sides will bring a microphone to you.

You could also text us questions.

Thank you for the very interesting and inspiring talk.

I have a question.

How does your small molecule actually affect the toxic protein so as to rid it from the cell?

That's an excellent question. We have done work to try to identify the target, you know, the protein target that Flo was talking about earlier, and we have identified a candidate target for this compound as being a molecule called PMed9, otherwise known as a cargo receptor. So when a protein is made, and this is now, I don't know, specialized a little bit in terms of the terms that I will be using, but a protein is made and goes into something called the secretory pathway. So a place where it can be packaged in order to be delivered to its ultimate destination. In certain cases, it would be delivered to the plasma membrane or the surface of the cell, for example. In some cases, it will be utilized and then it will be turned into the lysosome, which is basically the trash can for the cell. So in the case of a toxic protein, of course you would like it to go into the trash can. If you can, but it seems that the kidney cells have no capacity to really do that. So our compound essentially is able to facilitate by affecting the properties of this cargo receptor that I mentioned, this target, TMED9. It allows the mutant toxic protein to be promoted into trafficking through the cell and into the lysosome, the trash can. So it's essentially a way of getting rid of the protein by promoting its degradation, but in a novel way that we didn't know about before. That's what I mean, the beauty of science and discovering something that you never knew before. Now, of course, we have a lot of work to do to try to truly understand what this target is about, and we are partnered up to do exactly this kind of work now to take it to the next stage.

Thank you. Of course. Very interesting talk, very well presented. Thank you very much. I have two related questions. First is, when you find an effective chemical to attack this, do you— before it's fully gone through the FDA approval, do you offer it to those people suffering from the disease, the possibility of trying it, maybe low dose, you know, et cetera, realizing they're taking a risk? And the second question is, what— since you're able to develop so impressively, the organoids from blood cells. Can those organoids be developed into actual kidneys or partial kidneys? What is standing in the way, and how far along are we in that road?

Do you want to take the first question about trials? Yeah, so the first question, it's a complicated one to answer, right? So while we would like to offer those those drugs that have not been proved to be efficacious to patients, we first have to test the safety of the drug. So in Phase 1, typically people with the disease are not going to be enrolled in those clinical trials. In Phase 2, when we start to look at the efficacy of the compound, then people with the disease that volunteer to be part of this clinical trial can take part and actually take the drug. At that stage, Depending on how we set up the clinical trial, you may be taking the placebo or you may be taking the actual drug. In phase 3, then we go after a larger population that includes, of course, patients with the disease.

Absolutely. So yeah, in rare diseases, of course, that's the key point of developing this registry because we are going to go to those patients and find a way to populate our trial with patients to volunteer after informed consent, of course, to be a part of that phase 2 study, ultimately phase 3 study as well. So absolutely the partnership with patients is essential and it's a key component of what we do. To your other question about the organoids, this is a major aspirational goal for the field. As I mentioned in my talk, and I did that on purpose, if you compare the little mini kidney to a dime, you can see how small it is. So we have a long way to go to build an entire kidney. We don't even know how to hook up these things together so that they would form a functional kidney that actually takes blood and produces urine ultimately, which is what the kidney does. However, there are a lot of smart people working on this, basically all around the world. And there are several initiatives where people are trying to come up with new ways that we could try to use these technologies in order to ultimately be able to build a kidney. Kidney. There are several other initiatives to do this. One can use CRISPR technology, which the Broad had a big part in. And you can actually humanize, make human-like, a pig kidney. And some people are working on that approach as a way to replace human kidneys. So producing human-like kidneys in a pig and then being able to transplant those into humans. So there's an amazing array of different technologies that the Broad has contributed a great deal to. And I think the future is potentially bright, but we also have a lot of work to do before we can get there.

Thank you for your question. Thank you very much. Just a quick follow-up on the first part of the question. Those patients who end up with placebos in the trial, are they then offered the actual medicine unless it's found to be not good?

Yes, they are. Oh, hello. Thank you.

Um, uh, yes, right here. Oh, hi. Yes, um, so, uh, when you were talking about the phases and about how some of the drugs don't make it, uh, in the phases, uh, you mentioned something about a lack of efficacy and not safety, and I was wondering if you can expand a little bit more about the difference between safety and efficacy, if that's possible.

Yeah, sure. And so safety is, uh, about— so if you take this Is it going to be safe for you to take it? Or is it going to lead to maybe some toxicity that you're not going to tolerate? So that's all the, the safety trial that happened to make sure that this drug can be given to a large population. For efficacy, so you can have a really safe molecule that actually does bind to the target of interest. However, it's not going to stay there long enough in your body, for instance, or it's not going to go into the cell of interest. And so the efficacy here, the molecule is actually not doing what it's supposed to do. So if you think about the key and the lock, it seems like the molecule, the key is actually going in the lock, but it's not able to turn it off or on.

That's the efficacy issue. Thank you so much. Hi, very inspiring talk. Thank you. So in the first part of your talk, you talked about like the timeline to go from bench to bedside. And while the techniques that we use in preclinical drug development have changed tremendously throughout the last decades, it seems like this timeline hasn't moved at all. And the price, like the dollar amount to go from bench to bedside, even skyrocketed. I'm wondering if there is, in your opinion, a perspective for a scientific solution to this scientific regulatory problem. This is a really hard question.

I'm sorry. So yes, it does take a really significant amount of time because, you know, we are not doing blind experimentation. Patient anymore. And we want to make sure that we are creating the right drug for the right patient at the right time. And so it does take a lot of work from different team and different expertise to deliver such a compound that is going to reach the patient. In terms of cost, you know, I showed you the graph where about only 10% of the drugs that enter clinical trial actually are approved by the FDA. So a way to think about it is that when we buy a drug from the pharmacy, we're also paying the cost of all the drugs that have failed to reach approval.

And this is something that is key as well. Perfectly said.

I have nothing to add. There's a question which came in from text messaging. Somebody asked how exactly was the causal gene identified?

I'm assuming they're asking about Mach 1. Mach 1, yeah, so there's of course a paper published in Nature Genetics about the saga of identifying the mutation in the Mach 1 gene, but if you actually go right now and look into the Human Genome Project, you, in the sequence that's available, you will see that that area is a black box, and the reason for that is because Next-generation sequencing, the kind of modern technologies that were built to sequence the human genome at the scale that we had to do it, it still took 13 years, but nevertheless, those technologies fail to sequence through the VNTR region of mucin 1. So it was really heroic efforts by several scientists here at the Broad using old-fashioned Sanger sequencing and piecing together bit by bit that area of the DNA until the mutation mutation was identified. The mutation that was identified is a single letter insertion, a single C letter that is inserted in a string of Cs actually in the genetic code, and that causes a frame shift so that now instead of reading cat, for example, you would read at and then go from there. So the whole code is shifted by one letter such that at the end the protein that is produced from that genetic code is gibberish. And so that's how this toxic mutant protein is produced.

Thank you very much for a very educational talk and all the questions too. So my question is related to your very last slide that really made me feel very, very hopeful and Smile about the repurposing your drug to cure RP. And so my question is, when do you think you will begin a clinical trial for that? And is there any particular requirement for a particular type of RP? Because many, many different types of genes are involved. And I'm particularly interested because I'm working with many kids in India who have this disease, and some of them are going to come here. So I wanted to put that time, that thing in the time capsule that in 10 years from now, do you think this RP will be resolved?

I hate the question of time because it's always such a tricky one. The retinitis pigmentosa version that we are interested in at the present time is mutations in rhodopsin that cause a form of retinitis pigmentosa. There's a specific family of mutations that lead to that. There are several others, as you mentioned, and we simply have not looked at that yet. I thank you for your work with children who suffer from visual impairment or blindness. It's a terrific, huge problem. So I think that, of course, we're highly motivated to bring a therapy to all patients with all different diseases wherever we think that our treatment might have a positive effect. I think that we're quite far away because we're just beginning to do the work in cells, just beginning to do the work in mice just about this past week. Week we were looking at that. But we're very hopeful that the more that we learn from one disease might help us with our understanding of the next. And so while I cannot promise you a specific timeline, what I can truly promise you is that each and every one of us in this building is absolutely committed to bringing therapies for patients, and that's really important.

Okay, we've reached the end of the program, and just respecting everyone's time, we will not possibly be able to answer all the questions that came in through text. So we could try our best to get Anna and Flo to answer these questions offline, and the communications team can figure out a way to get those responses to you. But thank you, Anna and Flo, for a wonderful talk. Thank you, all of you in the room who attended today and our online audience on YouTube. Hope you will be able to join us for our next Broad@15 talk on genome editing on January 21st.

2020.

That will also be the first talk of the next year.

Thank you.