How Leyden Labs is revolutionizing flu protection with its intranasal antibody spray
Episode
32 min
Read time
2 min
Topics
Remote Work, Investing, Startups
AI-Generated Summary
Key Takeaways
- ✓Vaccine efficacy gap: Traditional flu vaccines average only 13% effectiveness against infection and perform even worse in elderly and immunocompromised populations — the groups most at risk. Leyden Labs' passive immunity approach bypasses this limitation entirely by delivering pre-formed antibodies directly into the nasal cavity, making protection independent of the recipient's immune system function.
- ✓Broad-spectrum antibody coverage: Leyden Labs' lead asset, PanFlu, uses the CR9114 antibody to neutralize all influenza A and B strains, with in vitro data also showing activity against C and D strains. This breadth means the spray does not require annual reformulation to match circulating strains, unlike conventional seasonal flu vaccines targeting only three subtypes.
- ✓Mucosal delivery mechanics: Administering antibodies intranasally coats the upper respiratory tract before viral replication begins, blocking infection at the portal of entry. Published data in Science Translational Medicine confirmed antibodies remain structurally intact and biologically active inside the human nose, resolving a key scientific uncertainty about whether nasal enzymes would degrade the molecules.
- ✓Preclinical efficacy validation: In nonhuman primate challenge studies using high-dose H1N1 administered intranasally, daily PanFlu spray produced sustained antibody trough levels and prevented viral replication in the upper respiratory tract. Consistent protection was also demonstrated across H5N1 and influenza B strains in mouse models, supporting progression into Phase 2 human trials.
- ✓Pandemic preparedness application: Because the spray delivers broad pre-existing antibody coverage, it can be stockpiled and distributed to households before a pandemic strain is identified. Leyden Labs received €20 million from the European Investment Bank via HERA, the EU's pandemic preparedness body, specifically to develop this rapid-response capability against novel influenza and coronavirus outbreaks.
What It Covers
Koenraad Wiedhaup, co-founder and CEO of Leyden Labs, and CSO Clarissa Kosch explain how their intranasal antibody spray delivers broad-spectrum protection against influenza and coronaviruses directly at the nasal entry point, addressing critical gaps left by traditional vaccines, backed by newly published preclinical data and €50 million in European funding.
Key Questions Answered
- •Vaccine efficacy gap: Traditional flu vaccines average only 13% effectiveness against infection and perform even worse in elderly and immunocompromised populations — the groups most at risk. Leyden Labs' passive immunity approach bypasses this limitation entirely by delivering pre-formed antibodies directly into the nasal cavity, making protection independent of the recipient's immune system function.
- •Broad-spectrum antibody coverage: Leyden Labs' lead asset, PanFlu, uses the CR9114 antibody to neutralize all influenza A and B strains, with in vitro data also showing activity against C and D strains. This breadth means the spray does not require annual reformulation to match circulating strains, unlike conventional seasonal flu vaccines targeting only three subtypes.
- •Mucosal delivery mechanics: Administering antibodies intranasally coats the upper respiratory tract before viral replication begins, blocking infection at the portal of entry. Published data in Science Translational Medicine confirmed antibodies remain structurally intact and biologically active inside the human nose, resolving a key scientific uncertainty about whether nasal enzymes would degrade the molecules.
- •Preclinical efficacy validation: In nonhuman primate challenge studies using high-dose H1N1 administered intranasally, daily PanFlu spray produced sustained antibody trough levels and prevented viral replication in the upper respiratory tract. Consistent protection was also demonstrated across H5N1 and influenza B strains in mouse models, supporting progression into Phase 2 human trials.
- •Pandemic preparedness application: Because the spray delivers broad pre-existing antibody coverage, it can be stockpiled and distributed to households before a pandemic strain is identified. Leyden Labs received €20 million from the European Investment Bank via HERA, the EU's pandemic preparedness body, specifically to develop this rapid-response capability against novel influenza and coronavirus outbreaks.
Notable Moment
Wiedhaup reframes the pandemic preparedness argument by pointing out that a nasal spray with pre-built broad protection could be shipped directly to people's homes at the first sign of an outbreak — potentially keeping economies open without waiting for a strain-matched vaccine to be developed and distributed.
Episode Transcript
Hello, and welcome to Beyond Biotech, the weekly podcast from Le BioTech. I'm Dylan Khesain, and this is episode 189 for the podcast. Today, I welcome Koenrad Viethhorpe, cofounder and CEO of Leiden Labs, and Clarissa Kosch, the company's chief scientific officer. Leiden Labs is pioneering a revolutionary non vaccine approach to combat respiratory viruses like influenza and coronaviruses. Recently, they published groundbreaking data in science translational medicine demonstrating that their intranasal antibody spray is safe, well tolerated, and delivers sustained protection right at the virus's entry point, the nose. This innovation addresses the shortcomings of traditional flu vaccines, which average just thirteen percent effectiveness against infection and provide even less for vulnerable groups like the elderly and the immunocompromised. We dive into the science, the company's journey since its 2020 founding, and their recent €50,000,000 European funding boost amid US biotech challenges. I hope you enjoy my conversation with Konrad and Clarissa of Leiden Labs. Konrad, welcome. Tell me a little bit about your background in life sciences, Delft and Leiden Universities, Columbia Business School, and now co founding Leiden Labs. Yes. And great to be here, Dylan. Thank you for hosting us. Yeah. So I have a background in, in from academia and biotechnology from actually, I'm here in in Leiden, sitting quite close to a deformer automata, where I studied life sciences across universities of Delft and Leiden. I was always intrigued in the application of these different technologies to how can we actually help people, to, to become better and also then the business side of that. So, after that, I worked briefly at a biotech company in the Bay Area, which I truly enjoyed in the business development. So already making that that jump towards the the business side. And then I started at McKinsey, working there in the biotech and life sciences practice. So serving large pharmaceutical companies but also a lot of, you know, smaller mid sized biotechs over the time. Was there for about twelve years both in The US and then in Europe. And on the side, I was always also working with smaller biotechs to help them start up, grow and was fascinated by that also from my experience at the time that I had in San Francisco at the biotech. And through that, I met my co founders at Leiden Labs who were the people behind Crucel. So that I embarked on the next journey towards Leiden Labs. Clarissa, it's great to have you here as well. You've built your career in immunology and virology. What drew you to join Leiden Labs and what's your role there? Yeah. Thanks, Dylan. And also seconding, Coonrad, thank you so much for having us. Yeah. So I think, if I think back, so, really, this opportunity came about really in the height of the COVID nineteen pandemic. At the time, I was actually working in pulmonary critical care at Northwestern Chicago at the time. So I was very aware, kind of, if …
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“Published data in Science Translational Medicine confirmed antibodies remain structurally intact and biologically active inside the human nose, resolving a key scientific uncertainty about whether nasal enzymes would degrade the molecules.”
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