My LDL Was 192. Then I Found the First PCSK9 Pill.
In a Nutshell
The FDA has approved the first oral PCSK9 inhibitor (anacetrapib/Lipfenra), which lowers LDL 56-59 percentage points more than placebo by blocking PCSK9 from degrading LDL receptors. This breakthrough stems from human genetics showing that people born with reduced PCSK9 function have lifelong 15-40% lower LDL and 47-88% fewer heart attacks. For patients unable or unwilling to inject monoclonal antibodies like Repatha or wait for twice-yearly inclisiran, this daily pill offers a reversible, needle-free option—though long-term cardiovascular outcomes data are still pending until 2029.
These notes were generated by AI and may contain inaccuracies.
My LDL was 192, even though I felt completely healthy. My cousin had the same kind of shock, very fit, but also with high lipids. In my family, we see numbers like this everywhere. My father is still recovering from a heart transplant after a heart attack. My grandmother died suddenly due to cardiac arrest. On the positive side, we now have the medication to tackle tough inherited risks like mine. Today, I use evolocumab, brand name Repatha, a PCSK9 inhibitor I inject every 2 weeks. It works so well that I fully believe as a longevity physician that it's made a bigger difference for my personal longevity than any other intervention, period.
But, what if it were easy as a pill? Because now, for the first time, that pill exists. The FDA just approved Lipfenra or anacetrapib, the first oral PCSK9 inhibitor in the United States. In its pivotal trials, it lowered LDL by roughly 56 to 59 percentage points more than placebo. The pill is part of a much stranger story, a story that starts with a scientist who was not studying cholesterol at all.
At the Clinical Research Institute of Montreal, Nabil Seidah and his two colleagues were screening genes involved in neuronal apoptosis and liver regeneration when they found a new gene. It was highly expressed in the liver, but no one knew what it was doing there. They called the protein NARC1. At that point, it was a scientific curiosity from the wrong field. Then, within months, patients gave it an entirely different meaning.
In France, Marianne Abifadel, Karim Bouillo, and their colleagues were studying families whose cholesterol levels made no sense. Their disease looked like classic familial hypercholesterolemia, the inherited form of very high LDL, but the known genes couldn't explain them. So, they traced the mystery to variants in a newly described gene. NARC1 at this point had become PCSK9, and an obscure laboratory finding had become the missing clue in families with runaway LDL levels. The French variants made PCSK9 too active. Some made the protein overactive, others helped it grip the LDL receptor too tightly. Either way, LDL rose, sometimes to severe levels. Researchers still don't know exactly how.
At UT Southwestern, Jay Horton's group tried a blunt experiment. They forced mouse livers to make extra PCSK9. The LDL receptors disappeared, even though the messenger RNA used to make those receptors did not change, meaning the body is still encoding and telling the body to make these LDL receptors, but they're being taken away. Three different scientific groups reported versions of the same finding.
So, why does this all matter? It's because LDL receptors are the liver's clearance machinery for LDL. They're like little hands, they go and pull LDL particles out of the blood. Fewer working receptors means LDL accumulates. That suggested that PCSK9 was not preventing the receptor from being made, it was doing something to the finished receptor. So, Helen Hobbs and Jonathan Cohen made the reverse prediction. If extra PCSK9 removes LDL receptors and drives cholesterol up, then a broken copy of PCSK9 should produce the mirror image, more working receptors and unusually low LDL.
They had built the Dallas Heart Study as what Hobbs called a human biology laboratory. The team recruited systematically through Dallas census tracts and households. About half the cohort is black, about 15% was Hispanic. They began with the people at the extreme, those with the lowest levels of LDL. Among the 64 black participants whose PCSK9 genes they sequenced, 11 carried a variant that reduced PCSK9 function. Across the full black cohort, about 1 in 50 carried one of two variants that prevented a full working protein from being made. Hobbs later said they had hit paydirt right away. The value of having a diverse cohort is not small. It was the very reason this protective biology came into view.
So, the carriers had LDL levels roughly 40% below that of non-carriers. But, the Dallas study was too small to answer the question that mattered most. Did these people actually have fewer heart attacks? For that, the scientists turned to Eric Boerwinkle and the ARIC study. That's A R I C, whose participants had already been followed for 15 years. Among black participants with specific loss-of-function variants, LDL average 28% lower, while observed coronary heart disease was 88% lower. Among white participants with a milder protective variant, LDL was 15% lower and coronary risk, or heart disease risk, was 47% lower.
I wouldn't promise anyone, right off the bat, that you'd get an 88% benefit from a drug impacting this gene. That estimate came from a small carrier subgroup with a huge confidence interval. So, there's a huge variance possible. The more meaningful lesson to take away was the impact of time exposed to atherogenic particles. So, these people did not begin their LDL lowering at age 60, which is sometimes, unfortunately, when we start interventions like medications for our patients. Instead, these are people whose arteries had been experiencing lower LDL exposure from birth.
So, there is an evolutionary reason why these variants can persist. Except in severe inherited disease, clinically important atherosclerosis often arises after reproduction. So, there's less evolutionary pressure against passing those variants on. But, I would not call PCSK9 itself neutral. The gene is deeply conserved and may have carried other historical fitness advantages. Late cardiovascular disease is a weak evolutionary filter is the main point.
Then, the Dallas team found the clearest human test, a human with essentially no working PCSK9. So, a 32-year-old woman had inherited two different inactivating PCSK9 variants, one from each parent. She had no detectable circulating PCSK9. Her LDL was 14. The original scientific report described her as a healthy, fertile college graduate. Detailed evaluations over the following decade found no apparent consequence beyond that remarkably low LDL. A handful of people cannot prove that every drug or technology built around PCSK9 will be safe. They tell us about the target, not every way we might manipulate it. But, this woman turned an abstract target into a human possibility. A person could have essentially no PCSK9 without an obvious deficiency syndrome.
Human genetics had now run the experiment in both directions. Turn PCSK9 activity up and LDL rises. Turn it down from birth and lifelong LDL exposure falls. And remember, high LDL alone doesn't tell you that PCSK9 is a reason for it. Most people with high cholesterol do not have any sort of strange mutation with their PCSK9 gene. And, you know, that's the same case for me. I don't have any particular genetic mutation that's causing my own familial lipid story. My family history explains why I care so much about this number. These stories from these studies explain why drug developers care so much about this particular target.
So, the next question was, what exactly does PCSK9 do to the liver's LDL receptors? So, to provide some context, an LDL receptor is not simply used once and thrown away. After it pulls an LDL particle into the liver cell, the LDL cargo is released for processing. And upon that release, the receptor normally returns to the surface to work again. It's reusable. PCSK9 interrupts that recycling. When it binds the receptor, it redirects the receptor towards degradation, to the garbage can, instead of back to the cell surface. So, that means fewer receptors survive to clear LDL from the blood.
Think of PCSK9 as a disposal tag. It sends a reusable LDL receptor towards the trash. Block PCSK9 and more of those receptors survive to catch yet another LDL particle. So, this is not a drug vacuuming plaque out of the artery. It changes the upstream traffic. Fewer LDL particles remain in circulation, so fewer are available to enter artery walls over time. This might be obviously a fantastic target for a drug. But, scientists ran into a drug design problem.
PCSK9 belongs to an enzyme family that usually acts like molecular scissors. But, mature PCSK9 behaves mainly as a binding protein. It does not offer a tidy little pocket that makes most enzymes easy targets for a conventional pill. Instead, PCSK9 grips the LDL receptor across a broad protein surface. So, what can we use? It turns out while we can't use small traditional pills to do the job, antibodies are excellent at covering broad protein surfaces. So, that is why the first successful treatment was so large. It was by design.
Alirocumab and evolocumab bind circulating PCSK9 and stop it from attaching to the LDL receptor. The target moved from genetics to drug development unusually fast. Hobbs later said Genesis took a little while to understand the result, while pharmaceutical companies got it right away. They saw the opportunity. Michael Brown and Joseph Goldstein had alerted Regeneron to the work. Hobbs then presented the data to the company's chief scientific officer George Yancopoulos. Regeneron ran with it and developed the antibody that eventually became alirocumab. Amgen independently developed evolocumab.
Early human trials showed dramatic LDL lowering. By 2015, just 12 years after the French family report, Praluent, which is alirocumab, and Repatha, which is evolocumab, had become the first approved PCSK9 drugs. Then the studies FOURIER and ODYSSEY Outcomes showed that. But benefit went beyond just a simply better lipid report. Across more than 46,000 high-risk patients, the antibodies reduced cardiovascular events on top of background therapy. That's real heart attacks, real strokes that impact real people.
This is the version I use. Repatha brought my own LDL from 192 to roughly 40. Every 2 weeks I inject it and I move on. But a great target doesn't guarantee that every drug aimed at it will work. Bococizumab initially lowered LDL by more than 50%. Unlike the other drugs, the fully human antibodies, it was humanized. And many patients' immune systems unfortunately made antibodies against that drug. Goes to show that the more natural seeming something is doesn't make it necessarily better. The LDL response weakened and became unpredictable. So Pfizer ended up stopping their research program. Human genetics had validated a target, but it doesn't pre-prove every molecule.
Once the antibodies worked, the next question was obvious. Do we have to keep catching PCSK9 after the liver make it or could we stop the message before the protein even exists? So as a quick review, DNA is the basic instruction layer. It tells RNA a certain message which tells amino acids to construct proteins in a certain way. If you go upstream enough, you want to get to the genes. So inclisiran goes one layer upstream. Instead of catching PCSK9 after the liver releases it, inclisiran uses small interfering RNA to destroy the messenger RNA that liver cells use to make it. A GalNAc tag helps steer the drug into liver cells. Less of this message means less PCSK9 protein is made. After starter doses on day 1 and day 90, a clinician gives inclisiran every 6 months. Its phase 3 trials showed about 50% placebo-adjusted LDL lowering. Its dedicated cardiovascular outcomes trials are still in progress.
That schedule also solved a different problem. For some people, two clinic doses a year fit much better than a daily pill or a self-injection every few weeks. This kind of RNA interference answered how to dose less often. It didn't answer whether a molecule could grip PCSK9 like an antibody and still be swallowed. There's a lot of problems translating injectables to oral medications, a story which we hear a lot about in peptides. And remember, if you don't already know, peptides are just small proteins. So, this is a recurring story. So, drug developers had to return to the same broad protein surface that had defeated the oral drugs two decades.
So, what are they going to do differently? The surface where PCSK9 meets the LDL receptor is broad and relatively featureless. A normal small molecule has nowhere obvious to sit. For almost two decades, attempts at making an oral drug kept running into that geometry problem. At Merck, Douglas Jones and a large cross-disciplinary team used a technology called mRNA display. So, the idea is almost like evolution in a test tube. Each candidate peptide is physically attached to the strand of messenger RNA that contains its recipe. Expose the library to PCSK9, pull out the peptides that bind, read their attached recipes, and amplify the winners for another round. That let the team research chemical shapes conventional drug libraries could not reach. They added amino acids beyond the standard biological set, closed the peptides into rings, and used structural biology to keep improving that fit.
And at the end of this all, the molecule that emerged, MK-0616, bound PCSK9 with an affinity of roughly 5 picomolar, an extremely tight grip. So, the team had created an antibody-like recognition in a much smaller structure. But finding the molecule was only half the problem. The usual way of building peptides, adding one amino acid at a time on a solid support, could not efficiently produce every design that medicinal chemists wanted to test. So, Merck's chemistry teams learned to build fragments in solution and join them, opening up new designs and eventually supporting manufacturing at scale. The pill required two inventions, the molecule itself and a practical way to actually make it at scale.
Inclisiran is a macrocyclic peptide, an engineered ring-shaped molecule. The ring is large enough to grip PCSK9's broad binding surface, yet compact and stable enough to put it into a tablet. Then swallowing added a third problem. The GI tract, or the gastrointestinal tract, is built to break peptides down and keep large molecules out. Think about it. Every time you eat a bite of steak or a bean, a soybean, we break it down, right? So that we can use the amino acids as nutrients. What do you do when you have an oral protein, essentially, that is meant to stay in one shape? So what they did was they added to the tablet sodium caprate to help Inclisiran cross the intestinal wall. Even then, only about 1% actually reaches the bloodstream. 1% sounds like a failed drug, but in this case it is enough.
So Inclisiran binds PCSK9 so tightly that the small amount reaching circulation can reduce free PCSK9 by more than 90% near peak concentration. The molecule had solved binding, manufacturing, and just enough absorption to do the job. The clinical question was whether that clever chemistry would actually lower LDL. The trial, ORION-10, enrolled 2,904 adults with prior cardiovascular disease or increased risk. Almost everyone was taking a statin. In 24 weeks, LDL fell 56 percentage points more with Inclisiran than with placebo. And apoB fell about 50% more. In 303 adults with the more common one-copy form of inherited high LDL, all on statins, LDL fell 59 percentage points more than with placebo. The pill had won the LDL problem.
But what about outcomes? We actually care about whether people are not getting heart attacks and strokes. Lipendra, which is the brand name of anlecitide, doesn't get to inherit the cardiovascular outcomes evidence of Repatha or Praluent simply because it reaches the same target. Coral Reef Outcomes is still ongoing. It's following 14,500 high-risk participants with the primary completion estimated all the way out in 2029. So, the evidence boundary is pretty clean. Lipendra's LDL and apoB lowering is proven. It's ability to prevent heart attacks, strokes, or cardiovascular death is still not yet proven in a product-specific outcomes trial. That being said, I think if we follow first principles, it follows that we probably will see lower effects, but we've got to wait till the trials say so.
Also, I want to bring up that the engineering victory creates a practical inversion. Turns out a pill can be more demanding than a shot in some cases. Taking a pill every day, first of all, it's every day, not a shot every other week. Plus, with this particular finicky situation, to take the pill every morning on an empty stomach with water, black coffee, or plain tea. Then you have to wait at least 30 minutes before eating or drinking anything else. If you take it after a meal, that can cut the already low absorption by roughly half. If needles are the deal-breaker, that routine might be just fine. But, if you forget daily medication or if you just need to eat the second you wake up or you just want milk in your coffee, an injection every few weeks might actually be easier.
Okay, so you're probably wondering, what are the downsides? Perhaps there's side effects. It turns out that in the larger trial, adverse reactions and discontinuations were similar with Lipendra and placebo. So, in the smaller inherited high LDL trial, dizziness was reported in 9% versus 4% and diarrhea in 7% versus 2%. That's a very reassuring first-year result, but it's not a lifetime safety records, and that is why phase four trials exist. For what it's worth, I've been on Repatha for a year plus, maybe a couple years now, and I have never had bad problems with it, no adverse symptoms. And I am somebody with the genetics to have a lot of adverse effects. For example, with statins, not to go down that rabbit hole, I had pretty severe muscle aches.
Leqvio is not a Repatha shot translated into tablet form. It's a completely new way to copy the same protective biology with a different set of compromises. The pill finally solved the oral problem while remaining reversible, which opened the next consequential question in the story. If nature has already proven to us that less PCSK9 could be protective, why keep taking a drug at all? Why not make this change once, make it permanent? After all, we already have this other injection that you can take once every 6 months. What about something that you only have to take once ever?
For one particular scientist trying to answer that question, the appeal is personal. Verve co-founder Sekar Kathiresan was already a cardiologist and cardiovascular geneticist when his seemingly healthy 42-year-old brother, who had been training for a race, suffered a heart attack and died. Kathiresan later said he tried to turn that negative energy into Verve. The ambition was to prevent that kind of surprise without asking people to navigate a daily treatment for the rest of their lives. However, as you might imagine, a one-time treatment's got to pass a very, very high safety bar. You can't take it back.
Studies Verve 102 and YOLT 101 use adenine base editing to change one DNA letter and switch PCSK9 off in liver cells. Gene editing. They deliver the editor in a liver-targeted lipid nanoparticle, making the liver one of the most tractable organs for this kind of in-body treatment. This is somatic editing, so it targets liver cells, not the eggs or sperm, so the intended change is not designed and cannot be passed to future children. These editors are not usually repairing the mutation that caused someone's high LDL. Most people with high LDL do not have a PCSK9 mutation. They're introducing the positive kind of mutation to turn off normal PCSK9 and recreate part of the protective biology that nature and some of the other studies had revealed.
In the heart two phase one interim analysis, 35 people received one infusion of Verve 102. At the highest dose, mean PCSK9 fell 88% and mean LDL levels fell 62%. That's miraculous. There were infusion reactions and temporary liver enzyme elevations, but investigators reported no dose-limiting toxicities in that interim data set. YOLT 101 has an even smaller report. Six people total with only three at the highest dose. So, these studies combined show that editing can lower PCSK9 and LDL in humans. They cannot yet establish the long-term safety of a change intended to last for years, perhaps for life.
Then, researchers posed a subtler version of the same question. Can we silence PCSK9 without changing the DNA letters at all? Epigenetic editing changes whether the gene is read, not by changing the genes. In mice, PCSK9 silencing lasts a year and persists after liver regeneration. Reversing it required a second targeted intervention, but it's reversible. STX1150 is now recruiting for phase one trial. We don't have the human LDL-lowering results quite yet, but what a crazy, miraculous story. This natural human experiment began at conception. These technologies would intervene later, adding delivery systems, unintended changes elsewhere, and durability questions that the genetic outliers that we see in nature can't answer for us.
If you could remove your PCSK9's function, would you do it? What if you couldn't undo it? For severe inherited disease or repeated failure of chronic treatment, durability might justify that harder exit. But, a one-time edit now has to compete with a put-in-pill that can be stopped tomorrow. So, pill or permanent solution that we don't really understand fully for a lifetime. I want to bring this back to my personal experience and that of many, many people all around the world. The problem with lipid issues is that you simply cannot feel them until it's too late. And for so many of us, we're doing everything right, we're exercising, we're eating well, and yet our family history is the trump card. That's not to say to completely give up and have a terrible lifestyle. It should, however, help you pay attention to your family history much, much more. And to get labs checked, to get your heart scanned, to do whatever you can to determine what your personal risk is so that you can take action.
After all the chemistry and the biotech talk, the decision is still how aggressive should you be given your personal risk? Which option has the best evidence and which route can you realistically sustain for the rest of your life? So, now we've got this oral PCSK9 inhibitor. It's still not at market, but it's been FDA approved. Would I switch? Maybe, eventually, but that's not the most interesting part of the story. Repatha brought my LDL to roughly 40. I tolerate it, it has direct heart outcomes evidence, and 26 injections a year is very manageable. But the bigger impact is for somebody who would never start an injection at all. They might now be willing to take a pill every single day, even if it has to be on empty stomach, and that has a high likelihood of saving their life or decreasing the likelihood of a terrible illness later.
This mystery began with families whose cholesterol made no sense. It turned when researchers found people at the other extreme, born with no PCSK9 and extraordinarily low LDL levels. If you want more first principle stories about drugs, tests, and technologies changing preventive medicine and longevity, subscribe here. And tell me below what matters more to you, avoiding injections, avoiding daily medication, or preserving an easy exit.
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