Radio-pharmaceuticals Are Changing the Rules of Cancer Therapy
Radiopharmaceuticals are rapidly moving from niche to mainstream in oncology research, with steep growth in the number of programs entering preclinical development over the last five years. This modality promises a highly specific, highly potent approach to tumor killing and is attracting interest not only from research teams but also from investment teams.
But there’s a gap between promise and execution. Radiopharmaceutical programs don’t struggle because the concept is unclear. They struggle because of the practical realities, such as targeting approach, radionuclide supply, biodistribution profile, and study design, are often underestimated or addressed too late.
To explore where programs succeed, where they stall, and what it really takes to move forward, Big4Bio spoke with the radiopharmaceutical and nuclear imaging team at Oncodesign Services, who shared a candid view of the opportunities and the realities shaping this fast-moving field.
May 14, 2026
Q. Why are radiopharmaceuticals getting so much interest?
Let’s start with the obvious: “By using a targeted approach, it becomes possible to concentrate a potent radiotherapy effect on cancerous tumor tissue while strictly limiting exposure to healthy organs and collateral damage,” explains Eftychia Koumarianou, Head of Molecular Radiotherapy and Preclinical Imaging. As she notes, this approach can help minimize the side effects typically associated with conventional oncological therapies (i.e. chemotherapy, immunotherapy), with clear implications for both efficacy and tolerability.
Outside of the obvious, Pierre Adumeau, Head of the Study and Research Team, explains that theranostics, a branch of radiopharmaceuticals coupling diagnostic imaging with a radiotherapeutic, offers something that conventional therapies do not: the ability to see where the drug is going, almost in real time. “You can visualize in the body exactly where the substance has gone,” he adds, “and that’s a powerful treatment tool.”
Q. What are the most common stumbling blocks and misconceptions in radiopharmaceutical development?
“There are a lot of misconceptions around scalability and reproducibility when moving from ‘cold chemistry’ to ‘hot chemistry’. It’s not implicit that the behavior of a molecule will transition seamlessly between the two,” says Senior Study Director Sarah Belderbos. Expertise in ‘cold’ chemistry (regular non-radioactive chemistry) does not imply expertise in ‘hot’ or ‘radiochemistry’. “When working with radioactivity, you need to know exactly what you’re doing,” Belderbos confirms.
“Supply is another big one,” Adumeau adds. “You need to know which radionuclides you want to work with, and then secure supply for the program. Only then can you set up the logistics. Production of radionuclides can only be done by a small number of facilities worldwide, and it requires specialist equipment and processes, and a large amount of energy.” Simply put, no radionuclide supply, no program.
“Program planning and logistics,” says Koumarianou, “is probably one of the biggest points of failure. Radionuclides typically have relatively short half-lives. You cannot just run a day late. Your tumor volume must be at the correct size and your models ready to go when the radionuclides arrive onsite. Because radionuclides are not easy to produce or transport, this all needs to be minutely planned and coordinated well in advance. Take Astatine-211 as an example: it has a half-life of seven hours. There is no room for error or delay. You need a research team that enjoys adrenaline!”
Q. Why is Astatine-211 getting so much attention at the moment?
Recently added to Oncodesign Services’ radionuclide supply chain, Astatine-211 is an alpha emitter that delivers high linear energy transfer (LET) over a very short path length, creating the potential for highly localized, potent effects at the tumor site. Unlike some other alpha emitters, it quickly decays to a stable or very low activity isotope, a major advantage in terms of off-target dosimetry estimations. “Furthermore,” Koumarianou adds, “it has potential for a more significant abscopal effect over some beta emitter-based therapies.” The abscopal effect is a radiation-triggered immune response to metastatic tumors.
“It has huge potential, but it comes with constraints,” Belderbos says. “The short half-life limits how far it can be transported and how it can be used, and as with every radionuclide, it has its own unique development challenges. It’s still early days for Astatine-211.”
This reflects a broader pattern in radiopharmaceutical development: the most promising tools are often also the most demanding in terms of planning and execution.
Q. Do complex logistics slow down radiopharmaceutical programs in the race toward IND?
“Actually no,” confirms Koumarianou. “Radiopharmaceuticals can feel complex and intimidating but because they do require an incredible amount of forward planning and tightly timed logistics, this tends to naturally remove the ‘white space’ from a program.”
And with a validated targeting molecule in-hand? “It’s possible to reach IND-readiness in about 18 months,” she advises. “Remember, radiopharmaceuticals are compact programs. The challenge is to successfully get the radionuclide specifically to the target. Once it’s there, the radiation does the work.”
Q. Just how important is the role of supply chain in early development?
It’s clear that radionuclide sourcing is a challenge that can’t be solved at the last minute. Koumarianou explains that the rising interest and investment in radiopharmaceuticals has increased pressure and focus on supply chains, leading to increased efforts to scale production over the last three or four years.
“But it’s still not as easy as ordering lab supplies,” she says. “As Pierre mentioned earlier, if you don’t have a reliable supply locked in and production and delivery aligned with your research timelines, there simply is no program.”
This also extends beyond early development. Supply must be in place to support clinical trials and to facilitate treatment when a drug successfully reaches the patient population. “Production scale-up is critical. This is another reason why the targeting molecule has to be high quality and translatable in early development. Supply is limited. Focusing the available supply on the truly progressible molecules will ultimately get new targeted radiotherapies to patients faster.”
Q. What should teams have in place before they begin?
“The characterization of the targeting molecule is critical,” Adumeau explains. “If binding is not selective enough or biodistribution is not appropriate, the entire program is compromised. No amount of radioactivity will compensate for a molecule that does not reach the right tissues in the right way.”
It is therefore key to have thoroughly screened the candidate, and target engagement and specificity should be confirmed. “You need a clear understanding of how the molecule behaves biologically: where it distributes, how stable it is, and whether it can realistically deliver the radionuclide to the intended site of action,” says Belderbos.
If targeting is not robust, the rest of the program cannot compensate for it. Biodistribution and translational relevance must be considered early. It is clear that these are not late-stage questions, but central to whether a program is viable.
Q. Any parting advice for teams interested in exploring this space?
“Forget everything you know from ‘cold’ chemistry and find the right people to accompany you in your development,” is the unanimous opinion. If one thing comes across clearly, it’s that radiopharmaceuticals cannot be done well in isolation. Surrounding yourself with experienced people and access to a solid supply and research network are critical components for success.
Radiopharmaceuticals offer an exciting path forward in oncology, bringing together specificity and powerful tumor-killing in a way that few other modalities can. Success depends on aligning biology, supply, and study design from the beginning, and being realistic about where the challenges lie.
For pioneering teams willing to approach the field with the required level of rigor, the opportunity is significant.
About Oncodesign Services
Oncodesign Services is a preclinical CRO focused on helping biotech and biopharma teams make confident, translation-focused progression. With 30+ years of experience in oncology, 20+ years in imaging, and 10+ years in radiopharmaceutical development, the company combines deep scientific expertise with a pragmatic approach to study design. Its work centers on generating data that stands up to investor and regulatory scrutiny, supporting the advancement of complex programs toward the clinic.