Building the path to 3D-printed organs, Cellbricks raises €10M for biofabricated tissue implants
Berlin-founded biotech startup Cellbricks Therapeutics has raised €10 million to advance its goal of 3D-printed organs, beginning with biofabricated human tissue implants.
If successful, Cellbricks is not just building better implants — it is laying the groundwork for manufacturing living human organs.
The financing includes a €7 million seed round and more than €3 million in additional non-dilutive funding currently under negotiation.
For patients with severe soft tissue loss, complex wounds such as full-thickness burns or blast injuries, and reconstructive defects, medicine still too often relies on compromise: invasive grafting procedures, synthetic implants and solutions that restore shape imperfectly but rarely restore living function.
Cellbricks Therapeutics has developed a proprietary biofabrication platform capable of producing vascularised human tissue implants. Combining human cells with biomaterials, it creates tissue constructs designed to be implanted into patients.
In the longer term, Cellbricks aims to build the biological and manufacturing capabilities needed to produce fully functional, implantable human organs.
I spoke to Alexander Leutner, Co-CEO and Co-Founder, Cellbricks Therapeutics, to find out more.
A personal turning point into regenerative medicine
Leutner describes himself as “an entrepreneur at heart and an engineer by training.”
Earlier in his career, he built the metrology startup Apodius, which was later acquired by Hexagon AB. He stayed on to lead the "Vision Systems" metrology business unit but admitted that the startup life was still calling.
At the same time, it was clear that he would need to donate a kidney to his younger brother. He began looking at startups in regenerative medicine, where he found Cellbricks Therapeutics.
The company was originally founded by Dr Lutz Kloke following his PhD, during which he developed and globally patented the light-based process that underpins the platform. Dr. Klokeliked the idea of bringing in an experienced entrepreneur, so that he could focus more on the scientist, and Leutner recalled:
“When I joined, the company was working heavily on the bioprinter itself, while also exploring the broader space of tissue models for drug development. Together we quickly said: Let’s go for the really big opportunity. Let’s focus on human tissue implants.”
From bioprinting tools to human tissue implants
Today, Cellbricks has two main areas. One is adipose tissue for wound healing and breast reconstruction, which is less complex than liver tissue. The focus on tissue bioprinting serves as a key validation programme, enabling the company to demonstrate that its platform can produce human tissue that can enter the clinic and function properly. At the same time, it's also working on the moonshot, which is organ tissue, including liver tissue.
The decision to start with tissue therapeutics is strategic. Leutner explains that as the company continues to develop its capabilities, tissues and programmes, it is also spinning out applications that can help patients sooner, while serving as validation milestones on the path towards tissues with organ function.
“It builds step by step. In wound healing, for example, we are targeting very complex wounds, including severe full-thickness burns in which the damage extends far beyond the skin surface.
We are not simply producing a superficial cover. This is where we develop the full platform and show that we can produce something large, viable and functional that works in large animals and, later, in the clinic. At the same time, it is a strong business case because there is currently no product on the market that truly solves these problems for patients. There are wound dressings, but they do not really solve it. There is autologous skin grafting, but that is extremely burdensome.”
From there, the next step is breast reconstruction, which uses much the same material but at a much larger volume and with even greater vascularisation requirements.
It's a process of solving the biology, engineering and translation challenges tissue by tissue. Living implants that survive, vascularize, integrate and function in the body are the essential stepping stones.
“You can see how that starts to lead towards organ tissue, which also requires larger, highly vascularised constructs. So we are building one stage on top of the other as we advance our platform,” explained Leutner.
A fully integrated approach to biofabrication
Leutner describes one of his biggest contributions as bringing in more pharmaceutical expertise:
“I hired a very experienced co-CEO, someone I would describe as a biopharma silverback, and he helped us set up the programmes properly. We also brought in a lot of new talent. Our team now includes 13 nationalities, with people coming from all over the world to Berlin to work on this."
While there are several bioprinting startups, Leutner sees Cellbricks as possessing a core competitive advantage:
"We have everything in-house — expertise across cells, biomaterials, the bioprinter, software, maturation, and now the translational capabilities needed to bring this into the clinic. I would say there is no other company in the world with all of that under one roof, and certainly not in Europe.
That is what makes us unique and gives us a real competitive advantage. Our scientists can, for example, say that to achieve fully vascularised tissue implants that work properly, we need to slightly adjust the biomaterial or the printing parameters, and we can do so directly. We have built a dedicated system for producing human tissue."
Further, Cellbricks stands out for its ability to produce tissue in the lab at speed.
“Because we use light-based bioprinting, we can work around 15 times faster than other bioprinting approaches,” explained Leutner.
“We have demonstrated that we can produce large volumes of tissue at high speed while maintaining full vascularisation. Our technology enables the creation of large tissue constructs that remain healthy and viable over time, as the cells receive sufficient nutrients and oxygen. That is what we are most proud of: producing large, vascularised tissue constructs that function in vivo.”
Solving the cell supply challenge
When it comes to 3D bioprinting, Leutner explained that historically, one of the biggest questions was where all the cells would come from:
“For organ tissue, for example, you cannot simply replicate liver cells from a patient at the scale required.”
But breakthroughs in cell biology, particularly in pluripotent stem cells such as iPS cells, have changed that.
“Large quantities of cells are becoming available, and many companies are emerging in that field. We can partner with those companies and secure the cell supply.”
Partnering with pharma to reach the clinic faster
For adipose tissue, Cellbricks uses patient-derived cells because that offers a faster regulatory pathway and development route. The liver programme uses stem-cell-based allogeneic cells, which can work across many different patients without severe issues. However, the real challenge now is scaling.
“Producing tiny tissue sections in the lab is no longer the main issue. Many groups can do that,” shared Leutner.
From hospital printers to pharma partnerships: the path to market
But what does the business model of 3D tissue (and later organ) printing look like in practice?
Leutner admits that from the visionary founder perspective, “ignoring time for a moment, the ideal future would be that the technology sits close to every hospital, perhaps even inside every hospital, and hospitals can produce their own tissue implants for patients."
"Later on, that could extend to tissue with organ function as well, not necessarily full organs immediately, but functional tissue.”
But today the company wants to partner its lead programme with a large pharmaceutical company. Canadian company Aspect Biosystems has already done something comparable with Novo Nordisk to develop cellular therapies for diabetes using stem-cell–derived islet cells in a deal worth $2.7 billion for one programme.
Leutner explained that for a small biotech, that model is attractive because it creates early revenue.
“There is an upfront payment, potentially worth tens of millions, followed by milestone payments as the programme progresses. The pharmaceutical company then launches the product, and the smaller company receives royalties. That is what we are aiming for, and we are already in discussions with two large pharmaceutical companies about those kinds of partnerships.
That model means we do not need to raise hundreds of millions of our own funds to commercialise the therapy independently. We can move forward through partnership, generate revenue earlier, and potentially even pursue an IPO on the back of that in a few years. That is our strategic path today.”
Berlin vs Boston: cost meets speed
Celbricks has offices in both Berlin and Boston. I was curious about the differences between the biotech ecosystems.
Despite the disadvantage that Berlin has no direct flights to Boston, Leutner sees speed as the biggest difference.
“A good example is regulatory approval for a small animal trial. In Germany, that can take between six and 12 months. In Boston, it can take around six weeks.”
Conversely, Boston is significantly more expensive, with higher labour costs, pricier lab space, and more costly professional services.
However, with most of the team based in Berlin — where laboratory setup is more affordable — the company can balance costs while benefiting from Boston’s faster, more innovation-driven ecosystem, particularly in areas such as regulation and clinical translation. For a small biotech, this combination is highly attractive. Funding will accelerate preclinical validation and enable Cellbricks Therapeutics to move from promise to proof, demonstrating that engineered human tissues can perform in clinically relevant models. This includes advancing its lead adipose tissue implant programme, launching up to three preclinical animal studies, and generating the necessary data to progress towards human trials.
Lead image: Cellbricks executive leadership team. From left to right: Dr Tobias Lam (CTO), Michael Kring (CFO), Dr Kathy Kordy (CMO), Alexander Leutner (Co-CEO), Dr Simon MacKenzie (Co-CEO).
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