{"id":919389,"date":"2026-10-07T12:24:22","date_gmt":"2026-10-07T12:24:22","guid":{"rendered":"https:\/\/www.newsbeep.com\/au\/919389\/"},"modified":"2026-10-07T12:24:22","modified_gmt":"2026-10-07T12:24:22","slug":"show-me-the-error-bars-before-you-sell-me-longevity","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/au\/919389\/","title":{"rendered":"‘Show me the error bars before you sell me longevity’"},"content":{"rendered":"

Deerfield\u2019s Jim Flynn on shrinking error bars, cutting through longevity hype, and why AI needs better loss functions. <\/p>\n

The Deerfield Managing Partner calls longevity \u201ca misnomer\u201d, is building a not-for-profit longevity center in New York to cut through the noise, and thinks AI models that can\u2019t run their own experiments won\u2019t learn much. He spoke to Longevity.Technology on the sidelines of ARDD 2026.<\/p>\n

Jim Flynn has spent 38 years in what he calls \u201cthe observation business\u201d. As Managing Partner and CEO of Deerfield Management<\/a>, the New York healthcare investor, he backs companies from university license to commercial launch, and has just watched one of them, Nuvalent<\/a>, go to GSK for around $10.6 billion. <\/p>\n

When the longevity sector asks whether big healthcare money is coming, Flynn is a useful person to ask. His answer is nuanced: he is skeptical of \u201clongevity\u201d as a frame, enthusiastic about healthspan, and building a not-for-profit center designed to tell people what actually works.<\/p>\n

Shrinking the error bars <\/p>\n

Deerfield\u2019s edge, Flynn says, starts with a simple idea: every investment reduces to an analysis of probabilistic cash flows.<\/p>\n

\u201cNo number that you collect, no survey that you do, no scientific information that you get is an exact number. It all has variance around it,\u201d he says. \u201cAnd if you have no certainty at all around what your return would be, your job is not to get better numbers, but to reduce the error bars. Our entire information apparatus is designed to reduce our uncertainty.\u201d<\/p>\n

Genetics is one concrete example. In 2015, GSK\u2019s head of genetics, Matt Nelson, published work in Nature Genetics showing that genetic support for a drug target roughly doubles the probability of clinical success. Deerfield hired Nelson and built a genetics team around him to sharpen its read on whether a trial will work.<\/p>\n

The rest of the Deerfield model covers the end market: how many people have the disease, how many are diagnosed, what payers will pay, how long and how costly recruitment will be. That analysis is the same whether a drug is in discovery or on the market, Flynn says. What changes is the work needed to push a company to its next value stage.<\/p>\n

De-risk first, build companies later, embrace China <\/p>\n

At the early end, Deerfield has tried to rework the classic biotech start-up. The usual route is to license a target, lease a lab and hire a team. \u201cAs soon as you do that, it\u2019s really hard to fail for less than $50 or $100 million,\u201d Flynn says, \u201cyet these are all 95% likely to fail when you license them in.\u201d<\/p>\n

Deerfield\u2019s answer is to own the labs and the discovery team, spread their cost across every program, and only form a company once a target is de-risked. That work sits in a New York building it calls Cure, which houses preclinical and clinical development teams, its own labs and around 30 university partnerships. Ideas come from those partners, from Deerfield itself and, increasingly, from China.<\/p>\n

Flynn sees no reason to treat Chinese assets as a threat. Chinese groups have advanced molecules against a very broad range of targets, he says, but most cannot take them to the US themselves. \u201cI see it as hugely synergistic. It doesn\u2019t have to be a competitive US-versus-China thing. It\u2019s drugs against targets that matter, and the job of the rest of us is to advance that and get it to people.\u201d<\/p>\n

\"\"Jim Flynn at ARDD 2026 (credit Michael DeStefano) Healthspan first, longevity later <\/p>\n

Asked whether the longevity movement merits Deerfield\u2019s time, Flynn is blunt. \u201cI just see it as a misnomer.\u201d<\/p>\n

He does see investment opportunities in healthspan, but he has noticed a pattern in longevity biotech presentations: companies hunting for drugs that might extend healthspan, \u201cbut which they can get approved for something else first\u201d.<\/p>\n

\u201cIt\u2019s an interesting admission,\u201d he says. \u201cThey\u2019re talking about something they can\u2019t really measure or define well enough to have a clinical endpoint relevant for approval.\u201d An investor, therefore, has to believe the acute indication is worth enough on its own, with any longer-term upside coming from later observation.<\/p>\n

Longevity.Technology\u2019s own modeling of the small- and mid-cap longevity biotech pipeline values it at $230 billion a year<\/a> in risk-adjusted peak sales on approved indications, with a further $173 billion a year of upside once a gerotherapeutic regulatory pathway opens.<\/p>\n

Should investors price that option in? Flynn wants something concrete. Multi-factorial biology means a \u201cmuddy drug\u201d, the antithesis of a gene therapy that replaces one missing protein. Gene therapy is \u201ckind of a straight line\u201d, he says; this is not. \u201cFrom an investment standpoint, what are my error bars? How do I assess that?\u201d<\/p>\n

On exits, Deerfield\u2019s rule is equally clear. \u201cIf someone will pay above our probabilistic value, it\u2019s gone. Private, public, it doesn\u2019t matter. If it\u2019s below, we\u2019ll keep building it.\u201d Nuvalent shows the logic: Deerfield founded it, owned 100% for five years, floated it at around $800 million and held it for four more before GSK\u2019s multi-billion acquisition.<\/p>\n

Flynn finds BioAge\u2019s exercise-derived research, partnered with Novartis, \u201creally interesting\u201d, but adds: \u201cIt will probably take a really long time to get a drug that you know what it\u2019s for. I just don\u2019t know how I would practically invest in something like that.\u201d<\/p>\n

For Flynn, the most underrated part of healthspan is mobility. \u201cWhen you look at exercise physiology and activities of daily living, your ability to actually engage and be mobile is super, super important. But where is that in a cellular clock sort of thing? It doesn\u2019t really come up.\u201d He reads mobility partly as \u201ca code name\u201d for very large markets such as osteoarthritis and cartilage repair.<\/p>\n

A \u201ctrue north\u201d longevity center <\/p>\n

Flynn is not content to observe. He is building a longevity center in New York, built around what is actually known.<\/p>\n

\u201cAlmost everybody who\u2019s in this space is selling something,\u201d he says. \u201cShould I take this peptide? Should I be micro-dosing GLP-1? Cold plunges, cryo, infrared \u2013 where do you go for a true north review of what has been shown biologically in humans, in terms of healthspan? What has been done to even show that this is safe?\u201d<\/p>\n

The center will start with a digital platform giving people neutral information. Users will be able to upload their own diagnostic data and work with an agentic system that tailors options to their profile and constraints \u2013 \u201cI have four hours to exercise a week, I hate this, I love that\u201d \u2013 with \u201cno bias behind it\u201d. The physical center will then let people access those interventions. <\/p>\n

Deerfield is also building a compounding lab within Cure, both to guarantee what is delivered and to run trials on it. \u201cWe intend to actually test this stuff,\u201d Flynn says. \u201cNone of this is for profit. This is all for true north information \u2013 and it\u2019s mostly because I\u2019m just really tired of all the misinformation.\u201d<\/p>\n

The digital layer should be low cost and widely accessible; physical services will be tiered and paid out of pocket. Full build-out is 18 months to two years away, with capacity aimed at thousands of people. In his view, clinical findings such as hypertension, an occluded artery or a tumor need a path into primary care, while the healthspan side is different but complementary. \u201cYour bone density is not going to be improved by going to the physician. It will be improved if you jump a lot.\u201d<\/p>\n

Prevention isn\u2019t new <\/p>\n

The longevity sector often holds up GLP-1s as proof that preventive therapeutics can become blockbusters. Flynn isn\u2019t persuaded the story is new.<\/p>\n

Byetta, the GLP-1 drug Amylin brought to market with Lilly around 20 years ago, was approved for type 2 diabetes, needed twice-daily injections and delivered far less weight loss, he notes; today\u2019s drugs refined an idea that had been around for well over a decade. Big pharma largely shunned the obesity space for years after fen phen, whose fenfluramine component was sold by American Home Products, was linked to heart valve damage and triggered multi-billion-dollar litigation. \u201cEveryone ran away from the obesity space. GLP-1 is not a new idea at all. I\u2019ve been in this observation business 38 years, and it doesn\u2019t seem new to me.\u201d<\/p>\n

That doesn\u2019t make him dismissive of prevention. \u201cIf someone comes up with something that prevents osteoarthritis, that is going to be a colossally huge drug.\u201d But he argues it need not be a drug at all.<\/p>\n

A foundation model of the joint <\/p>\n

Deerfield has been working with the Hospital for Special Surgery (HSS) on foundation models of the joint. As with Parkinson\u2019s disease, Flynn says, joints let you link imaging with clinical histories, biomarkers and genetics to build generative models that are highly predictive.<\/p>\n

He offers a striking statistic: a 16-year-old girl is significantly more likely than a 16-year-old boy to tear her ACL in the same sport. The reason is anatomical variation, and how that variation combines with the way someone runs, cycles or moves through daily life. \u201cThat doesn\u2019t matter whether you\u2019re taking a drug or not. It\u2019s actually the combination of your daily activities and how you do them.\u201d <\/p>\n

Link a foundation model to a wearable and it could deliver haptic feedback that corrects movement. \u201cIf you want to prevent osteoarthritis in ways that might require knee replacement, an ACL tear or hip replacement, it doesn\u2019t have to be a drug. It could be a wearable.\u201d <\/p>\n

That is different from today\u2019s consumer devices, he stresses. \u201cThe problem with Oura Ring and Whoop is they\u2019re giving you information relative to averages. It has no idea how much sleep you need.\u201d <\/p>\n

Mobility suits this approach because much of it is physics. \u201cYou can create functional predictive models that course-correct where you end up, in a way that may be much more profound than a drug.\u201d<\/p>\n

AI needs a loss function <\/p>\n

Flynn\u2019s most pointed view is on AI drug discovery, including the wave of foundation-model companies setting up their own labs. His critique: they can\u2019t create a useful loss function. <\/p>\n

\u201cWhat made ChatGPT work was that they used words rather than letters. When you look at chemistry, it\u2019s very hard to use atoms for the same reason.\u201d Mining historical data won\u2019t get you far, he argues. A model has to make a prediction, have that molecule made and tested, learn whether it was right, and repeat. \u201cNo matter how they build their lab, it\u2019s going to take them three-month cycles to make anything. They\u2019re not going to learn anything for ages. So our approach is to focus on high throughput tokenized synthesis of molecules so that you can actually have a loss function that a foundational model can actually learn from.\u201d<\/p>\n

The bigger prize may be in the clinic. Flynn expects foundation models of disease to create a new generation of trial endpoints, accepted by the FDA, that compare patients against a neutral digital model. Measuring a qualitative sign such as tremor in Parkinson\u2019s requires long trials with many patients. Asking instead whether a patient is ahead of or behind where the model says they should be could mean \u201csmaller trials, faster trials, more accurate trials\u201d.<\/p>\n

For a sector still fighting to define its endpoints, that may be the most useful message Flynn has to offer.<\/p>\n

Read more of our on-the-spot coverage of ARDD 2026 \u2013 CLICK HERE<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"Deerfield\u2019s Jim Flynn on shrinking error bars, cutting through longevity hype, and why AI needs better loss functions.…\n","protected":false},"author":2,"featured_media":919390,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[34],"tags":[486292,486293,64,63,487631,137,500,487632,352568],"class_list":["post-919389","post","type-post","status-publish","format-standard","has-post-thumbnail","category-healthcare","tag-ardd","tag-ardd-2026","tag-au","tag-australia","tag-deerfield-management","tag-health","tag-healthcare","tag-jim-flynn","tag-nuvalent"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/919389","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/comments?post=919389"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/919389\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media\/919390"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media?parent=919389"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/categories?post=919389"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/tags?post=919389"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}