Radiopharmaceuticals, also known as radioactive tracers or medicinal radiocompounds, are drugs containing radioactive isotopes that have been in use to treat cancer for over 80 years. Radioisotopes share chemical properties with stable isotopes of the same element, but emit small amounts of radiation, which can be detected by specialized imaging equipment as they bind to the surface of cells across various tissues in the body. This allows medical professionals and researchers to visualize the internal workings of the body and identify any abnormalities or diseases. These compounds are not limited to their use in nuclear medicine to diagnose, monitor, and treat diseases; Radiopharmaceuticals are also a vital component of clinical research, enabling researchers to study biological processes and track the effectiveness of treatments.

The global market for radiopharmaceuticals was US$6.1 billion in 2019 and is expected to reach US$12.6 billion by 2027. As research continues to progress, the use of radiopharmaceuticals is expected to grow even more. Read on as we explore the fascinating world of radiopharmaceuticals and how they are used in the medical and clinical research fields!

The Significance of Medicinal Radiocompounds in Clinical Research

Radiopharmaceuticals have become increasingly important in modern medicine due to their ability to provide precise, non-invasive diagnostic and therapeutic procedures. They are widely used in the diagnosis and treatment of cancer, cardiovascular disease, thyroid disorders, and more. Radiopharmaceuticals can also be used to study diseases and their progression, helping researchers to develop new treatments and therapies. The use of radiopharmaceuticals in clinical research has provided significant breakthroughs in disease diagnosis and treatment, as well as providing an essential tool for studying the efficacy of new treatments and therapies for a variety of diseases.

Applications in Clinical Research

1. Disease detection and monitoring

One of the key applications of radiopharmaceuticals in clinical research is the use of PET (Positron Emission Tomography) scans and SPECT (Single Photon Emission Computed Tomography). The radioactive isotopes used in these scans are absorbed by the body’s tissues and organs and emit gamma rays. By detecting these gamma rays, clinicians and researchers can create detailed images of the body’s internal structures that are not visible with traditional imaging techniques and identify any abnormalities. This technology is widely used to track the progression of disease and the effectiveness of treatments. For example, because iodine-131 concentrates in the thyroid gland, liver, and parts of the brain, it can be used to monitor diseases of these organs, such as goiters, tumors, and Grave’s disease. Liquid solutions containing sodium-24 can also be injected systemically to help clinicians identify areas of obstruction in blood flow, particularly in the case of heart disease.

2. Therapeutic applications

Additionally, medicinal radiocompounds have uses in therapeutic applications when used at much higher doses. In cancer treatment, for example, radiopharmaceuticals are used to deliver radiation therapy directly to cancer cells. This is called targeted radiopharmaceutical therapy or molecular radiation therapy, and it is more effective than traditional radiation therapy because it is well-equipped to target specific receptors of cancer cells and limit the damage done to surrounding healthy cells. Because this form of therapy is effective both for localized and metastatic tumors, a wide range of patients can benefit and are likely to experience fewer side effects and better outcomes.

The following drugs are examples of radiopharmaceutical therapies approved by the United States Food and Drug Administration (FDA):

• Radium-223 dichloride (Xofigo®) for metastatic prostate cancer in the bones (May 2013)
• Sodium iodide I-131 (Hicon®) for thyroid cancer (1971)
• Lobenguane iodine-131 (Azedra®) for adrenal gland tumors (July 2018)
• Lutetium-177 (Lutathera®) for somatostatin receptor (SSTR) positive gastroenteropancreatic neuroendocrine tumors (GEP-NETs) (January 2018)
• Yttrium-90 (Zevalin®) for non-Hodgkin lymphoma (2002)

Safety Considerations of Radiopharmaceuticals

Radiopharmaceuticals may pose some risk to patients, healthcare providers, and the environment due to their radioactive properties; therefore, strict safety measures need to be implemented when handling and using these drugs. Personnel involved in the preparation, administration, and disposal of radiopharmaceuticals must be adequately trained and certified to handle them safely. These include minimizing exposure time, maximizing the distance from the radiation source, and utilizing personal protective equipment (PPE) such as gloves, gowns, and face shields. The use of radiation monitoring devices and the implementation of radiation safety protocols are also necessary to ensure that radiation exposure is within safe limits. Although the importance of proper preparation and safety cannot be overlooked, the current literature supports the potentially lifesaving benefits associated with exposure to radiopharmaceutical tracers and diagnostic nuclear medicine as outweighing its safety risks.

Regulatory Considerations of Radiopharmaceuticals

In the U.S., the Centre for Drug Evaluation and Research (CDER), a department within the FDA, and the Nuclear Research Commission (NRC) are the two main federal regulatory agencies overseeing the control of radiopharmaceuticals. Radioactive Drug Research Committees (RDRC) also contribute to providing guidance for clinical trials involving radiopharmaceuticals. Recent examples of these guidelines include the following:

• Microdose Radiopharmaceutical Diagnostic Drugs: Nonclinical Study Recommendations, 2017
• Compounding and Repackaging of RPs by State-Licensed Nuclear Pharmacies and Federal Facilities, 2016
• Clinical Trial Imaging Endpoint Process Standards Guidance for Industry, 2015
• Investigational New Drug Applications for Positron Emission Tomography (PET) Drugs, 2012
• PET Drug Applications – Content and Format for NDAs and ANDAs, 2011

These regulations ensure that the drugs are safe and effective and that they are used appropriately. The FDA regulates the development and approval of investigational radiopharmaceuticals for diagnostic and therapeutic use in medical research, whereas the NRC aims to ensure the safe use of radioactive substances in research. RDRCs are responsible for reviewing and approving studies involving the use of radioactive drugs in humans.

Environmental Impact of Radiopharmaceuticals

The use of radiopharmaceuticals can also have an impact on the environment; therefore, proper disposal of radioactive waste in accordance with all local, state, and federal regulations is essential to prevent contamination of the environment. Aside from the FDA and NRC providing safe waste disposal guidelines, the Environmental Protection Agency (EPA), the Occupational Safety and Health Administration (OSHA), and the Department of Transportation (DOT) are also responsible for governing radiopharmaceutical use.

Conclusion

Radiopharmaceuticals are revolutionizing clinical research by providing accurate and precise imaging and targeted therapy. Their increasing importance in modern medicine has led to significant advancements in the diagnosis and treatment of various diseases. The application of radiopharmaceuticals in clinical research has led to a better understanding of the body’s biological processes and has contributed to the development of new drugs and therapies. Although safety and regulatory considerations must be considered to ensure their safe use in clinical research, there are exciting new developments in the application of radiopharmaceuticals to look forward to in the future of clinical trials and medical advances.

Leveraging CRO Partnerships in Radiopharmaceuticals Clinical Trials

Radiopharmaceuticals have enabled innovative advancements in the study of numerous diseases, including cancer, heart disease, and thyroid dysfunction, to name a few. However, clinical trial sponsors looking to work with this unique class of drugs must address complex considerations, as well as determine the appropriate applications for the disease in question. Navigating these types of studies may present unique challenges, but they can be circumvented by enlisting the aid of full-service contract research organizations (CROs) with years of experience across each of these disease indications.

Vial is a next-generation, global CRO equipped with a curated team of industry-trained clinical professionals across nine therapeutic areas: Oncology, dermatology, ophthalmology, gastroenterology, central nervous system (CNS), cardiology, medical device, rare disease, and digital therapeutics. As a tech-forward organization, Vial CRO offers the latest digital tools and clinical trial management solutions to drive efficiency across complex clinical trials, such as those involving radiopharmaceuticals, across a variety of diseases.

Visit Vial CRO’s website or contact a Vial representative today to discover how we are empowering scientists and helping people live happier, healthier lives!