Maxime Klausen, Young Researcher Starting Grant 2025 : Developing smart medicine to target tumours

The PSL Young Starting Grants Call for proposals is aimed at early-career researchers who have recently been recruited or are about to join Université PSL. It provides funding of up to €150,000, designed to help them launch their research projects and prepare an application for an ERC grant.

Could you introduce yourself? 

The core of my academic training is in chemistry, although my path has been strongly shaped by interdisciplinarity and collaboration across scientific fields. I completed a Masters degree in Macromolecular Chemistry followed by a PhD in Organic Chemistry at the University of Bordeaux, before moving to the UK where I worked as a Research Associate, first at the University of Edinburgh, and later at Imperial College London and the University of Oxford. All these roles have led me to see chemistry as a “keystone” science in interdisciplinary research, in the sense that a well-designed molecule or material can hold together “building blocks” of biology, physics, and engineering, to build a functional architecture that can benefit people’s lives. Conversely, a keystone’s full meaning is perceived through the bricks around it.
Today, I work as an Assistant Professor at Chimie ParisTech - PSL University in the institute of Chemistry for Life and Health Sciences. Our research group specialises in therapeutic molecules for precision medicine, and I am currently building my research theme on “smart” materials for healthcare. My hope is to make a difference on some of the many unaddressed healthcare challenges in this world. One way to do this is to develop more targeted, less invasive, and ultimately more effective therapies, which is the core of the project I proposed.

Your project in a few words 

The project’s overarching objective is to make treatments for rare and/or aggressive cancers smarter, safer and more tolerable for patients. Although cancer research has made huge progress over the last decade, nearly 50% of cancers are still treated with toxic metal-containing chemotherapy drugs. These drugs can be very effective, but they attack both cancer cells and healthy cells indiscriminately, which causes extremely detrimental side effects that often make treatment intolerable over time. Our aim is to rethink this approach by creating “intelligent medicine” that is initially inactive and non-toxic when administered to a patient, but can be activated on demand, when and where they are needed, inside the tumour cells. To achieve this, we will design molecules that trap the chemotherapy drug in an inactive “caged” state. This cage then needs a combination of two specific keys to be opened. The first key is a specific biological signal, present only in cancer cells, which concentrates the chemotherapy in the right place. The second key is light: by shining light on the area to treat, the drug is released onto the cancer cells and unleashes its therapeutic action on target without side effects. The project will focus on preparing the best combination of metal-based drug, photo-cage and biomarker and optimise their molecular properties to achieve the best therapeutic results. Although these “smart” molecules will be developed at a fundamental research stage, the long-term vision is that it could one day allow doctors to activate a cancer drug precisely at the right time and place simply by shining light on the cancer. Light has a lot of therapeutic potential; we’re hoping projects like this can be a step towards fulfilling this potential and generating precise, patient‑friendly medicine. 
 

Why is this research question important today?

Cancer still causes 1 in 6 deaths in the world, so improving treatments remains a major research priority. New innovative therapies are continuously developed, but toxic metal-containing chemotherapy remains a standard treatment. The associated side-effects represent a huge burden on the physical and mental health of patients and their families, often exacerbating health inequalities and even leading to treatment withdrawal. Aggressive and rare cancers, that are difficult to treat, often require very high chemotherapy doses administered over a short period, simply because the body would not tolerate the treatment longer. This means many people suffer as much, or more, from the side effects than from the disease itself, but also that the cancer may not have been treated long enough, which increases the risk of relapse and treatment resistance. This is a real “vicious circle” that ends up being a key factor in low survival rates, in pancreatic cancer for example. We therefore need to rethink how we administer such drugs so they can be more selective and effective in the long term, but also more humane, and designed for a better quality of life. By using light and biological signals as triggers, we aim to take a step towards a new generation of treatments that give patients more precise, sustainable and equitable care. This is not only a scientific challenge but also a societal one.

How does the funding impact your research? What does the grant concretely enable you to do in order to carry out your project?

This grant is very important to help me launch my independent research programme as a young investigator. Experimental research, particularly at the interface between several scientific disciplines, is expensive to sustain day to day. This funding will allow me to acquire the chemicals and specialised equipment needed for our light-activated molecules, all the way from their design to testing them in biological models. It will save a lot of time and create a favourable research environment to pursue more ambitious scientific ideas. Most importantly, it will also allow me to build a small team fully dedicated to this project. Thanks to this support, I have just recruited my first postdoctoral researcher who will be a key team member bringing experimental leadership and supervision support for the students working on the project. Above all, this grant will give us the stability to focus primarily on science. It’s a major boost of trust, responsibility, and motivation to drive these ideas forward.
 

Why did you choose PSL to pursue your research?

Université PSL offers one of the best academic environments in the world. At Chimie ParisTech - PSL, I am lucky to work alongside talented and inspiring researchers, renowned for their work in medicinal chemistry and metal-based therapeutic molecules, which synergises perfectly with my background and research goals. Beyond the immediate environment of our research group, the wider PSL ecosystem brings together experts in engineering, physics, biology, and even cancer specifically with the Institut Curie, which is a unique asset to generate translational technologies with a real impact on healthcare. 
 

What are the next steps?

For the project, the next steps will focus on building and testing our first “smart drug” prototypes and validate how these compounds behave in the lab. Once we identify the most promising candidates, we hope to move on to biological testing in tumour cell models, in-vitro, then in-vivo. On a more personal level, I’m hoping to build upon this dynamic to come up with new exciting ideas that address unmet medical needs. This implies applying for other young researcher grants, in France and at the European level, and continuing to grow my independence as a scientist. In the long term, like many researchers in my domain, I’m very driven by the hope of making a real difference on global health. Smarter treatments are one way to do this, but there are so many more challenges and inequalities to tackle, from rare diseases to early diagnostics, or solutions for populations with limited access to healthcare facilities. My goal is to drive my research in directions where chemistry can make a real difference for people.

Any advice for those considering applying to the PSL Young Researcher Starting Grant call?

I think it’s important to build a project that reflects who you are. Choose an area of research where you feel confident, focus on ideas that genuinely excite you, and add some vision and curiosity by pushing them beyond the beaten path. Trust your instinct too; if something does not feel right as you write your project, reviewers will probably feel it. Don’t overlook aspects that will make your proposal credible and tangible: concrete timelines, deliverables, success criteria, and a detailed budget. And of course, all this is easier said than done. So perhaps the most important piece of advice is to surround yourself with good mentors and colleagues. Don’t be afraid to ask for their feedback, all it can do is strengthen your proposal.