Nucleus RadioPharma Appoints Former FDA Commissioner Dr. Stephen Hahn as CEO to Lead the Next Era of Radiopharmaceutical Innovation
Nucleus RadioPharma, a next-generation contract development and manufacturing organization (CDMO) focused exclusively on radiopharmaceuticals, has appointed Dr. Stephen M. Hahn as its new chief executive officer. The appointment represents a major inflection point not only for the company but also for the broader field of radiopharmaceuticals—a sector widely seen as one of the most promising frontiers in oncology.
By bringing Hahn on board, Nucleus RadioPharma is making a clear statement: it intends to accelerate the scale-up of infrastructure, supply chains, and operational models that are required to make targeted, minimally invasive cancer therapies broadly accessible to patients worldwide.
A Leadership Appointment with Strategic Weight
Dr. Stephen M. Hahn brings to Nucleus RadioPharma a career that uniquely blends regulatory authority, clinical expertise, and executive leadership. Most prominently, Hahn served as the 24th commissioner of the U.S. Food and Drug Administration (FDA) from 2019 to 2021, a role in which he presided over the agency during one of the most turbulent times in modern healthcare history. His tenure at the FDA coincided with the COVID-19 pandemic, a period that forced the agency to simultaneously manage urgent pandemic-related approvals while maintaining oversight of the broader pharmaceutical and medical device landscape.
Following his time at the FDA, Hahn joined Flagship Pioneering as a CEO-partner, where he co-led the launch of Harbinger Health, a biotechnology company focused on early cancer detection. Before entering the regulatory sphere, Hahn built his career as a physician-scientist, holding senior roles at the University of Pennsylvania and later serving as chief medical executive at MD Anderson Cancer Center in Houston, Texas, one of the world’s leading oncology institutions.
This blend of perspectives—spanning patient care, cutting-edge oncology research, regulatory oversight, and biopharma company building—positions Hahn as an executive uniquely capable of tackling the challenges that stand in the way of radiopharmaceutical adoption.
Radiopharmaceuticals: The Next Frontier in Precision Oncology
Radiopharmaceuticals are rapidly emerging as a transformative modality in cancer treatment. Unlike traditional chemotherapies, which circulate broadly through the body, or even some biologics, which can sometimes lack precision, radiopharmaceuticals deliver targeted radiation directly to cancer cells. These therapies harness radioisotopes attached to molecules that bind selectively to cancer markers, ensuring radiation is delivered precisely where it is needed—while minimizing damage to surrounding healthy tissue.
The promise is enormous:
- Greater precision in targeting tumors.
- Less toxicity compared to conventional chemotherapy and radiation.
- Improved quality of life for patients, given the minimally invasive nature of treatment.
Indeed, radiopharmaceuticals are increasingly viewed as the next wave of precision oncology, complementing immunotherapies, CAR-T cell therapies, and antibody-drug conjugates (ADCs).
But despite their clinical promise, access remains limited. Unlike traditional biologics or small molecules, radiopharmaceuticals face unique challenges:
- Fragile isotope supply chains – The global availability of key isotopes such as Lutetium-177 or Actinium-225 is limited, fragile, and prone to disruption.
- Specialized GMP-compliant facilities – Manufacturing radiopharmaceuticals requires infrastructure capable of safely handling radioactive materials, far beyond what most CDMOs or pharma companies currently possess.
- Distribution and operational bottlenecks – With short half-lives, radioisotopes must be manufactured, quality tested, and shipped quickly to treatment centers—something that traditional pharmaceutical supply chains were never designed to handle.
As Dr. Hahn himself put it:
“Radiopharmaceuticals are the next frontier of precision oncology care. But without the infrastructure to deliver these treatments, their impact is fundamentally limited. At Nucleus RadioPharma, we have an extraordinary team that is committed to breaking those barriers. Together, we will scale the systems and infrastructure needed to make these lifesaving therapies available to all who need them.”
Why Nucleus RadioPharma is Positioned to Lead
Founded in 2022 through a collaboration between Eclipse, a venture capital firm specializing in industrial and healthcare innovation, and the Mayo Clinic, one of the world’s premier medical institutions, Nucleus RadioPharma has quickly established itself as a specialized CDMO uniquely focused on radiopharmaceuticals.
Since inception, the company has raised $72 million in funding, with notable participation from AstraZeneca, signaling strong biopharma industry interest in this emerging therapeutic category.
Infrastructure Strategy
Nucleus is actively building a network of advanced facilities designed specifically for radiopharmaceutical research, development, and commercial-scale production. Key sites include:
- Mesa, Arizona – A state-of-the-art facility designed to integrate research and production capabilities.
- Spring House, Pennsylvania – A hub for both R&D and commercial manufacturing.
- Rochester, Minnesota – Currently undergoing GMP-readiness, this facility will play a critical role in supporting clinical trials and early-stage production.
These facilities represent more than just bricks and mortar. They symbolize an attempt to create an end-to-end radiopharmaceutical infrastructure that can move seamlessly from isotope production and drug development to clinical trial supply and eventual global distribution.
Industry Reaction to Hahn’s Appointment
Hahn’s appointment has been met with strong endorsement from the oncology and venture communities.
Justin Butler, partner at Eclipse and board member of Nucleus, underscored the significance:
“Steve’s experience as both a physician treating patients and as a leader at the FDA brings an unparalleled perspective to Nucleus as the company works to build the infrastructure needed to accelerate the widespread availability of radiopharmaceuticals. His new role is a major indicator to the oncology community that radiopharmaceuticals are the future of precision cancer treatment, and that Nucleus is poised to lead the next era.”
Meanwhile, leaders from the Mayo Clinic expressed confidence in Hahn’s ability to advance radiopharmaceutical innovation:
Dr. Cheryl Willman, Executive Director for Mayo Clinic Cancer Programs, stated:
“With one of the largest cancer theranostics practices in the world, we have a responsibility to drive continual innovation and develop new targeted diagnostic and therapeutic radioisotopes for our patients. With Steve’s exemplary leadership skills and expertise as a cancer physician and scientist, our future could not be brighter.”
Strategic Roadmap Under Hahn’s Leadership
In his first year as CEO, Dr. Hahn plans to focus on several core initiatives:
- GMP Readiness in Minnesota – Completing regulatory readiness at Nucleus’s Rochester facility to ensure compliance and accelerate clinical trial support.
- Expansion of R&D Capabilities – Investing in discovery and development pipelines that can bring new radiopharmaceutical candidates to market more quickly.
- Data Platform Launch – Rolling out Nucleus’s proprietary data platform, which will support clinical and operational insights to streamline development and improve patient outcomes.
- Strategic Partnerships – Establishing collaborations with pharma, isotope suppliers, and healthcare systems to expand access and distribution.
Looking ahead, Nucleus aims to dramatically increase manufacturing capacity over the next five years while simultaneously advancing initiatives that improve global patient access to radiopharmaceutical therapies.
The Broader Implications for Oncology
The appointment of Dr. Hahn comes at a critical moment in oncology innovation. In recent years, radiopharmaceuticals have demonstrated clinical efficacy in diseases such as prostate cancer, neuroendocrine tumors, and hematological malignancies. Regulators, payers, and providers alike are beginning to recognize their potential.
Yet, as the sector moves from early clinical validation to commercial expansion, manufacturing and distribution bottlenecks threaten to slow progress. Nucleus RadioPharma’s mission—to build the infrastructure necessary to solve these barriers—could prove pivotal in determining how quickly radiopharmaceuticals move from experimental therapy to mainstream oncology care.
If successful, Nucleus and companies like it could reshape cancer treatment standards in the same way immunotherapy redefined oncology over the past decade.
The arrival of Dr. Stephen M. Hahn as CEO of Nucleus RadioPharma is more than a leadership change—it is a signal to the oncology community that radiopharmaceuticals are entering a new phase of maturity. Backed by strategic investors, anchored by partnerships with leading institutions like Mayo Clinic, and guided by an executive with rare regulatory and clinical experience, Nucleus is positioning itself at the forefront of the precision oncology revolution.
As Hahn himself emphasized, the promise of radiopharmaceuticals is not limited by science but by infrastructure. By tackling these challenges head-on, Nucleus RadioPharma is seeking to ensure that the next generation of cancer treatments is not just discovered but delivered—to every patient who needs them.
