Radiopharmaceuticals: Status, Regulatory Landscape and Future Perspective.

Radiopharmaceuticals are biologically active molecules labeled with radionuclides that have advanced the possibility of the nuclear medicine. They support non-invasive, high-resolution diagnostic imaging of molecular and physiological processes in vivo. The techniques such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT) utilize short-lived β⁺ and γ-emitting isotopes to generate highly sensitive, three-dimensional assessments of biological function. In therapeutic applications, radionuclides that emit β⁻ particles, α particles, or Auger electrons enable targeted delivery of cytotoxic radiation to diseased tissues, while limiting off-target exposure to the healthy cells. The choice of radionuclide is guided by decay characteristics, half-life, production feasibility, and cost, and is coupled to a small molecule, peptide, antibody, or nanoparticle via bifunctional chelators that ensure in-vivo stability and precise biodistribution. Recent approvals highlight this clinical momentum, including Copper-64/Copper-67, a chemically matched theranostic radionuclide pair that reduces chelator-related variability and streamlines diagnostic therapeutic supply chains, Lutetium Lu-177 dotatate, an FDA approved radioligand therapy, and Lutetium Lu-177 vipivotide tetraxetan, a prostate cancer targeted radioligand therapy illustrate the clinical momentum of this field, yet hurdles remain in large-scale isotope supply, formulation robustness, and regulatory harmonization. This review highlights key innovations in vector design, radionuclide production, and formulation; explores how artificial intelligence is transforming imaging and therapy planning; and clarifies the shifting regulatory landscape for clinical translation. By highlighting both current achievements and future research priorities, we provide a comprehensive framework by integrating productions challenges, formulation considerations, and regulatory harmonization into a unified perspective that deliver precision imaging and personalized therapy.