5PSQ-059 Case report: unexpected adverse reaction to (⁶⁸Ga)Ga-DOTATOC

<h3>Background and Importance</h3> (⁶⁸Ga)Ga-DOTATOC is a radiopharmaceutical preparation (composed of gallium-68 and a radiopharmaceutical kit, SOMAKIT TOC) used in positron emission tomography (PET) for imaging somatostatin receptor overexpression in patients with gastroenteropancreatic neuroendocrine tumours, in order to localise primary tumours and their metastases. Data on adverse drug reactions (ADRs) associated with this preparation are scarce in the literature.^{1 2} We report a case following administration of (⁶⁸Ga)Ga-DOTATOC that has not been previously described in the literature. <h3>Aim and Objectives</h3> This study explores the case of a patient who presented to the nuclear medicine department for this examination. The patient reported a metallic taste in the mouth immediately after the administration of (⁶⁸Ga)Ga-DOTATOC with no prior history of this symptom. <h3>Material and Methods</h3> Our pharmacovigilance centre was notified and we searched the European pharmacovigilance database, EudraVigilance to investigate a possible link between this symptom and (⁶⁸Ga)Ga-DOTATOC. <h3>Results</h3> The patient’s general condition remained stable and this symptom did not recur. An investigation into other possible causes, including excipients and radiolabelled impurities (with a free gallium content of 0.52%, within the ≤ 2% recommended threshold), was conducted. Based on the chronology of the event, our pharmacovigilance centre deemed the reaction probably imputable to (⁶⁸Ga)Ga-DOTATOC. However, the radiopharmaceutical preparation was not contraindicated for this patient. EudraVigilance, the European database for adverse drug reaction (ADR) reports, has identified 60 individual cases of SOMAKIT TOC up to 29 September 2024. Two of these cases reported dysgeusia with this drug. <h3>Conclusion and Relevance</h3> This symptom, a metallic taste in the mouth, is probably an ADR associated with (⁶⁸Ga)Ga-DOTATOC. Pharmacovigilance plays a crucial role in identifying and documenting rare ADRs that have not yet been described in the literature. The use of the European database, EudraVigilance, and the World Health Organization’s global database, VigiBase, can provide valuable insights into the safety profiles of diagnostic or even therapeutic radiopharmaceuticals. <h3>References and/or Acknowledgements</h3> Somakit Toc - European public assessment report - Product information. https://www.ema.europa.eu/en/documents/product-information/somakit-toc-epar-product-information_en.pdf Summary of product characteristics for GalliAd, 0.74 −1.85 GBq, radionuclide generator. https://www.ire.eu/medias/296/UK.pdf <h3>Conflict of Interest</h3> No conflict of interest