Background and Importance Clinical trials (CTs) involve different procedures in which Pharmacy Service (PS) participates. Difficulty evaluation of these activities is important to analyse global CTs complexity, which could be used as a measure of resources needed in each CT by PS.

Aim and Objectives To assess the complexity of the CTs in which PS participates, depending on the CTs’ characteristics.

Material and Methods Observational retrospective study which includes CTs started from 2014 to August 2023 when CTs unit was founded as an independent area in PS. CTs’ characteristics were collected: medical service involved, pathology, uni/multicentric and phase. Complexity scale from Calvin-Lamas et al., 2012 was used. Complexity punctuation was assessed according to the procedures where PS is involved (investigational products (IP) receipt, conservation, assignment, preparation, conditioning and dispensation; randomisation and blinding). Complexity levels were established: low (until 10 points), moderate (11–19 points) and high (more than 19 points). Complexity analysis was calculated for global, medical service, pathology and CTs’ phase. Information was obtained from Fundanet®.

Results 101 CTs started during the studied period. Distribution between medical services was: 48.5% (49) oncology, 21.8% (22) infectious diseases, 20.8% (21) neurology, 5.9% (6) rheumatology, 2.0% (2) surgery and 1.0 (1) psychiatry service. Pathologies more investigated were related to human immunodeficiency virus 16.8% (17), breast cancer 12.9% (13), Parkinson’s disease 12.9% (13), colorectal cancer 7.9% (8), Alzheimer’s disease 6.9% (7), lung cancer 5.0% (5), gastric cancer 5.0% (5) and rheumatoid arthritis 5.0% (5). According to CTs’ phase, 1.0%; 25.7%; 67.3% and 5.9% corresponded to phases I; II; III and IV, respectively. 99.0% were multicentric and 52.5% (53) were unblinded.

CTs which required two pharmacists represented 37.6% (38). Aseptic preparation was needed in 47.5% (48) and dispensation to the research team was needed in 74.3% (75).

Overall average complexity was moderate (15.1±4.0). 16.8% (17) presented low complexity, 70.3% (71) moderate complexity and 11.9% (12) high complexity. The higher complexity corresponds to neurology CTs. Pathologies with higher complexity were gastric cancer (20.2±2.6), Alzheimer’s disease (18.1±2.2) and lung cancer (18.0±3.3). Average complexity was moderate for all CTs’ phases, being the punctuation higher in phase II CTs (16.6±2.3), followed by phases I (16.0±0), III (15.1±4.2) and IV (12.2±4.8).Classifying by triennium, median CTs complexity has gradually increased:11.0±1.0 for 2014–2016,13.7±8.9 for 2017–2019 and 15.3±5.2 for 2020–2022. In 2023, complexity remained at 16.8±2.4.

Conclusion and Relevance The complexity of CTs has increased over the years, although most CTs have a moderate complexity regardless of their phase. The most complex CTs correspond to oncological and neurological pathologies. Carrying out this type of evaluation is important to optimise resources and to know in which PS procedures it is necessary to invest new resources.

References and/or Acknowledgements 1. Calvin-Lamas M, Pita-Fernandez S, Pertega-Diaz S, Rabunal-Alvarez MT, Martín-Herranz I. A complexity scale for clinical trials from the perspective of a pharmacy service. Eur J Hosp Pharm.2018 Sep;25(5):251–256.

Conflict of Interest No conflict of interest.