IMUNEXUS THERAPEUTICS LTD - How Imunexus Builds Next-Gen Antibody Medicines

We’re joined by Philippa Lewis, Chair and CEO of Imunexus Therapeutics, to break down a protein engineering platform that aims to “turbocharge” existing biologics like monoclonal antibodies, enzyme therapies, and even cell therapies. The idea is modular: attach small human protein components that can add new targeting, adjust immune activity, extend half-life, or enable multi-pathway action, while keeping the parent drug’s core function and manufacturability intact. For anyone tracking biotech innovation and the ASX biotech IPO pipeline, this is a clear look at how platform companies try to build repeatable value.

We also get into the business case hiding in plain sight: more than 100 FDA-approved monoclonal antibody drugs exist, and many are now off-patent. Imunexus argues that enhancing validated medicines can deliver differentiated next-generation biologics plus new intellectual property, giving pharma a way to refresh valuable assets as biosimilar competition grows. We talk partnering and licensing dynamics, why early preclinical deals can be meaningful, and what “capital-efficient” development looks like when you’re designing trials to generate fast, decision-grade data.

On the science side, the focus lands on IMX39 for multiple sclerosis, a market measured in the tens of billions of US dollars. Beyond relapse control, the discussion centres on progression, remyelination, and the possibility of repairing nerve damage, supported by preclinical results and a planned path to first-in-human studies in Australia under the TGA. We then zoom out to the wider pipeline, including IMX101 for small cell lung cancer, IMX113 for Gaucher disease with half-life extension, and a regenerative medicine angle for stem cell therapy enhancement.

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Transcript

Andrew Musgrave

Welcome again to ASX Briefs. And today we're joined by Philippa Lewis, the Chair and CEO of Imunexus Therapeutics Limited, a biologics company that has developed a proprietary plug-and-play protein engineering platform capable of turbocharging existing antibody and enzyme-based drugs with new therapeutic properties. Philippa, thanks for joining me today and welcome to the ASX Briefs Podcast.

Philippa Lewis

Thank you, Andrew. Pleasure to join you today.

Andrew Musgrave

Now, Philippa, for listeners that are new to the Imunexus story, can you explain how your platform works and what it means to turbocharge an existing biologic drug like a monoclonal antibody?

Philippa Lewis

Yeah, look, I think the best way to explain it is, think of the Imunexin platform as a plug and play, or more correctly, it's really a modular technology for biologic drugs. We engineer small human protein molecules, we call them imunexins, and they can be attached to existing biologics such as monoclonal antibodies, enzymes, or even a cell therapy, and it gives it a completely new therapeutic capability. So, for example, through the attached imunexins, we can add the ability to target a specific disease tissue, activate or suppress the immune system, extend the drug's half-life, and even enable it to act on multiple disease pathways simultaneously. But importantly, what we do when doing this is we're preserving the original therapeutic function and the manufacturability of what we call the parent drug. So, the result is essentially a next generation biologic that has the potential to be more effective than the original medicine, but while creating entirely new therapeutic applications and importantly, new intellectual property.

Andrew Musgrave

Now the FDA has approved over 100 monoclonal antibody drugs, many now off-patent. Why is that such a compelling opportunity for a technology that can add new therapeutic properties without disturbing the original drug?

Philippa Lewis

Look, it creates an enormous opportunity for us as a bispecific company. Over the past 25 years, you're quite right, there's been many, many monoclonal antibody drugs developed. The pharmaceutical industry has invested literally hundreds of billions of dollars developing these successful biologic drugs. Many of those drugs, by the way, work well, but they also have limitations, and an increasing number are now coming off patent. So rather than starting from scratch for us, our platform allows us to build on these validated medicines by adding new therapeutic properties while preserving what was their original and quite good therapeutic function. This can potentially improve efficacy and create differentiated new generation products. We also generate new patent protection around the enhanced molecule. So, for pharmaceutical companies, it offers a way to revitalize, if you like, valuable biologic assets. And for Imunexus, it creates multiple partnering and licensing opportunities across a very large and growing biologics market. So that application in terms of creating new intellectual property is quite critical for some of these blockbuster drugs that are around the monoclonal antibody market who are coming off patent and have a lot of competition from generics. So, we have the ability to attach an imunexin and create new intellectual property, but importantly to improve the efficacy of the drug itself.

Andrew Musgrave

Looking at IMX39, which was co-developed with the Baker Heart and Diabetes Institute, it has shown a 70% improvement in disease symptoms and restoration of motor function in animal studies and even outperform Gilenya®head-to-head. Can you unpack what makes IMX39 different from existing MS treatments, particularly its ability to promote nerve repair through remyelination?

Philippa Lewis

Yeah, sure. Look, most current multiple sclerosis therapies are designed primarily to suppress the immune system and reduce inflammation. And while they are effective at reducing relapses of the disease, generally they do not repair any damage that's already occurred within the central nervous system, nor do they have an impact on the underlying progression of the disease. So, though the treatments, there's many of them, it's a $27 billion US market, it's a great market to be in, and there are blockbusters in that market. The issue is they don't actually address what is the underlying cause of the progression of the disease. They also don't do any reversal of the disease. So, we're a first in-class application. IMX39 is a tri-specific biologic. It targets the upstream cause of the disease while an environment that supports the remyelination and damaged nerve repair. That's critical. That's the step change in the disease because we've seen in our preclinical studies compelling data that shows the remyelination occurs with the application of IMX39. And you're quite right, it demonstrated a 70 to 80% improvement in disease symptoms, restored motor function, promoted extensive remyelination, and has a greater than 50% efficacy than fingotamil, which is the active ingredient of Gilenya®, the drug you just quoted. Gilenya®is a popular diagnosed drug for diagnosed MS, particularly in the US. But interestingly, it's come off patent in the last couple of years and its revenues have dropped, as we say, they usually do, off patent. But we've got the capacity to actually attach an imunexin to Gilenya®and create an effectively new IP. So, getting back to IMX39, this demonstrated favourable preclinical safety study showed no toxicity at all. So, if these biological effects translate into humans, then IMX has the potential to represent a really meaningful advance over current approaches and indeed even the potential for some nerve damage repair. So quite an incredible, if you like, quite an compelling preclinical data for us to focus on, which is one of the reasons we picked it as our lead drug candidate.

Andrew Musgrave

Okay, and with the global MS market estimated at over 27 billion US dollars, as you mentioned, and growing, and a US addressable market alone exceeding US $5 million, how are you thinking about the path from these pre-clinical results through to phase 1B and 2A human trials in 2026 and 2027?

Philippa Lewis

Yeah, look, for us we selected IMX39 because it simply was an exciting, had such exciting and compelling data. So, we've selected it to take it through the clinic. Our strategy is to progress IMX39 through a really capital-efficient phase 1B/2A clinical program. And we're going to do that in Australia under the TGA's clinical trial notification pathway, in and we're going to commence that in 2027. Now, the study is designed to generate first in human safety, pharma kinetic, how the body affects the drug, that is, you know, and target the engagement data. So, together with early biological evidence of efficacy, very informative MRI and biomarker endpoints, we hope to be able to conclude a phase 1/2A clinical trial in 2027. Now we believe if we get meaningful data readouts, we may be able to achieve some pretty significant readouts in approximately six months. So, the study's been designed with an expansion option. If the six-month safety and MRI and biomarker data care data outcomes are positive, the patient cohort can be expanded to generate additional efficacy data without initiating an entirely new study. So, what we've got is a flexible, if you like, clinical study as a phase 1/2A. So, our objective is to generate sufficient clinical validation to support strategic partnering or licensing discussions, given the strong appetite among pharmaceutical companies for innovative multi-specific biologics. And the fact that many transactions can occur at the preclinical or early clinical stage. So, we believe this represents a logical value maximizing pathway for the company, and we want to actually execute on that as quickly as we can. So, we're expecting to see some very positive data in early 2027.

Andrew Musgrave

Now, beyond IMX39, you're advancing additional candidates, namely IMX101, IMX113, and IMX114. Can you give us any information on these candidates and what they're targeting, how these are progressing and how they are being developed?

Philippa Lewis:

Yeah, of course. Well, as I mentioned, Imunexus is a platform technology, plug and play, as we say, and we have quite a growing pipeline of additional candidates. IMX101 is an oncology strategy. It's a T cell engaging bispecific antibody for small cell lung cancer. Now, small cell lung cancer is an unmet need, and the mortality rate is extremely high. In fact, people diagnosed with this disease really only get seven or eight months of life. So, there's a lot of interest in small cell lung cancer. Now we have very compelling animal data, similar to IMX39, in fact, and that compelling animal data showed 100% tumour killing capacity. We're really interested in this one because there's been one or two bispecific deals done with small cell lung cancer, enormous in size, by the way, and done at preclinical. So, we think our IMX101 is a very good target to progress through into preclinical, compelling animal data, and then commence some discussions with big pharma, who have already had a bit of a watching brief on IMX101 and have actually asked us, once we've produced that compelling animal data, to re-engage with them. I think that particular application has a big future. The second application that we're working on is called IMX113. Now, 113 is an enhanced enzyme replacement therapy for a rare paediatric disease called Gauchet's disease. It's an inherited disease, and babies and children are born with this disease. It's a highly reimbursed therapeutic disease, if you like. So, it's a quite a nice target commercially to look at. So, it's rare, but it has a high reimbursement through the FDA. IMX113, we've developed a particular imunexin that is what we call our half-life extension imunexin. A lot of drug candidates, a lot of drugs, I should say, monoclonal antibodies and other therapeutic drugs, work, but one of their limitations is they don't last very long in the body. Now, the current treatment for Gaucher's disease does not last very long in the body. And so that affects the, if you like, the dosing application for that particular therapy. So, our half-life extension, we've done some preclinic work on that with our half-life extension IMX, Imunexus, and it's proved to be very promising. So, we want to do a little bit more work on 113 and again introduce our data for preclinical to big pharma because their interests are in enhancing the current Gaucher's treatment, particularly because of that half-life extension opportunity. And then lastly, we we're also targeting the stem cell therapy. We have an imunexin that's been demonstrated through discovery activities to have an enhanced application for mesenchymal or stem cell therapies. We've developed to that to improve the therapeutic potential and regenerative part of stem cell medicine. So together, each of these programs I think go a long way to demonstrate the versatility of the Imunexus platform because it's across neurology, oncology, rare diseases, and regenerative medicine. So, we see Imunexus not just as a simple single drug company, but as a platform biotechnology company with the potential to generate multiple high-value therapeutic programs which lead to strategic partnerships and licensing opportunities over time.

Andrew Musgrave

And how is the company approaching partnerships? Do you have a strategic or commercial partnership model?

Philippa Lewis

Yes, we do. We have a partnership model with a listed biotech right now that we're doing some work with on the mesenchymal stem cells. And the model is also, as I said, it's well tread globally. Typically, a company like us, we could be quite small as we are. But if we have a platform, we have multiple targets and we do some discovery and preclinical work, and that discovery and preclinical work then creates sufficient data, usually, for a larger company to come and say, look, we'll fund your research now on that target. In funding that target for us, the R&D and the extended preclinical work, it triggers, if you like, an option to license. And so, this is where these early deals are done, and they're done at exceptionally high value. So, we have a table of deals that have been done over the last five years. Most of these deals are done at preclinical or at discovery, and they're done with at sort of early phase down payments of tens of billions of dollars, and the actual milestones are usually up in the billions. So, we're working in a very interesting area of biotech. So, we're working in a very in a very interesting area where biotech companies can commercialize their assets early and commercialize them in partnership or under licensing deals with big pharma. And those models, that business model, as I said, is well trodden. In other words, we're a follower, we're not a leader of that. And we've got, say, in the last four years, at least 20 deals well publicized that have been done in exactly that process as I described it, which is early engagement with big pharma, development of your preclinical targets, some good assets in terms of data being created, and then entering into a co-development and licensing program. So, there are examples of companies like us who have continued to develop their targets. They've picked one or two and they've taken them right through the clinic. But the way they've done that is they've done two or three very big deals with early-stage targets. So, we have the opportunity to run, as I say, a parallel strategy with Imunexus to develop our own targets to a certain point and out license, or perhaps select one or two and take them right through.

Andrew Musgrave

And looking at the finances, the company has completed a $2 million capital raise alongside the conversion of shareholder loans and convertible note options into equity. So, how has this reshaped the balance sheet heading into the new financial year?

Philippa Lewis

Well, look, we've restructured the balance sheet and I suppose you could say tidied it up. When we do list, we'll have just under a hundred million shares on issue. Very few you know, one minor selection of convertible notes, but a very small amount, less than one percent of the of the holding. Currently we know that we'll have at least 40% of the stock will be escrowed. So, it's going to be a neat, clean share register. We've got some good lead shareholders, and we'll expand that that base of solid, experienced biotech investors to raise the capital. So, yeah, look, we've got as I say, we've got it we've got a neat register, tightly held, and no other real complications, if you like.

Andrew Musgrave

And touching on the proposed IPO, what will an ASX listing mean for the company's ability to fund its pipeline and platform partnerships going forward?

Philippa Lewis

Oh, look, it's critical to for us to IPO. As everybody probably knows, biotech’s typically have raised capital by listing. Of course, we've raised private capital to get where we are, but there is an inflection point, if you like, when you are wanting to take a company like this to maximize its destiny, let's say, fulfill its destiny. And its destiny is to run a number of different targets, run that parallel business strategy in terms of early licensing and also the development of our own in-house targets. Now, the listing allows us to access public money, which is which is really important. Importantly, the capital we will raise at the listing, a vast majority of that capital is going to be applied to our clinical trial. Prohibit us from pursuing some preclinical work on those other targets, but the vast majority of our focus is to maximize the clinical outcomes on the MS   IMX39 target, because we know that data, if that data is good, that's going to create an enormous opportunity for investors and for the company to transact, if you like, an early out license at a you know higher value, let's say. So being listed, of course, gives us public scrutiny. Where we become well governed, of course, as a publicly listed company. and we also create a stronger, if you like, global profile. We'll have watching briefs created with a number of big pharma companies who have expressed interest over the years and once we're listed and we're funded well, I think that gives us a certain validation and it opens the doors for us to access that capital and to build out some shareholder value. So, the listing is a very important strategy for Imunexus and it's timely because we're ready, if you like, we're a company that's really ready to be a listed company now. So, for us it's a very important step towards our future.

Andrew Musgrave

And finally, Philippa, with a planned ASX listing, clinical development plans to advance IMX39 towards human trials and expansion of your clinical pipeline, what are some of the key messages you want to leave with investors over the next six to twelve months?

Philippa Lewis

Oh look, I think we're an exciting company. We're one of the first drug development companies to hit the exchange for a number of years. We're the only bispecific company that we're aware of in Australia, so we're a homegrown Australian bispecific company. We're keeping company, though, in an area of biotech that is, you'd have to say, is some of the most exciting products coming forward. And because we're a platform, I think we're a lower-risk biotech because we have many shots of goal and we have a very flexible, novel, and I think a very elegant technology. And we have the capacity, I think, to engage in commercialization in ways that are not so common coming out of Australian biotech’s. And that's because the area we're in, in that whole area of in biologics, improving current biologics and working, if you like, off the back of validated medicines, does create, I think, a better risk profile for us as a company for investors. I think we're a company that's going to have a lot of activity. And as a listed company, I'm hoping and planning that we'll have a very active calendar of announcements. And the reason for that is that many, many biotech’s they list, and they raise some capital, and then they're going very headlong into the clinic to take that drug through the clinic. And they’re announcements and their positive news can take a long time to come through. With Imunexus, I think we're going to have a lot of interesting news and of and strong news flow because the company's activities are going to be really quite dynamic. So, I think for investors, we're an exciting-looking company. We're unique in many respects in Australia, but not unique in the world, but our applications have been carefully selected to be part of big marketplaces of oncology, paediatric diseases, inflammatory and autoimmune diseases, etc. So, I think for investors, we're a good company to have a look at for those reasons.

Andrew Musgrave

Okay, Philippa, with compelling clinical pre-data behind IMX39, a promising pipeline and an ASX listing on the horizon. It's shaping up as a defining year for the company. So, thanks for joining me today on the podcast, and we look forward to further updates in the upcoming months.

Philippa Lewis

Very, very grateful for your time today. Thank you.

Andrew Musgrave

That concludes this episode of ASX Briefs. Don't forget to subscribe, and we look forward to catching you on our next episode.