Cancer is the leading cause of death by disease among children. Although research has raised the survival rate to over 80%, the results vary according to the type of tumour, and the side effects of treatments are still very severe. It is therefore important to maintain the research effort to develop more effective and less harmful treatments. The international non-profit organisation Innovative Therapies for Children with Cancer (ITCC) has analysed 61 phase I and II clinical trials conducted between 2003 and 2018. The results of this organisation, which brings together 63 paediatric oncology departments, including the one at Vall d'Hebron University Hospital, have been published in the Journal of Clinical Oncology and have shown a clear trend towards biomarker-based treatments and targeted therapies using a variety of molecules. This approach towards personalisation is limited by the slowness caused by administrative procedures, especially in trials originating from academic research.

Dividing the period analysed into two stages, from 2003 to 2010 and from 2011 to 2018, shows a substantial change in trial design. In the second phase, the majority of trials were oriented towards new biomarkers. This evolution responds to key discoveries, such as the fact that half of childhood tumours have treatable genetic variants and the success of therapies using inhibitors targeting the activity of ALK, BRAF, or TRK genes, among others.

At the same time, there has been an increase in combination treatments, including various targeted therapies or the combination of targeted therapies with chemotherapy or immunotherapy.

Another highlight is the increase in trials that include a Paediatric Investigation Plan (PIP) agreed with the European Medicines Agency (EMA), which enhances their potential to be recognised and replicated at the European level.

However, despite progress, there are still significant challenges to overcome. Approval times by ethics committees and regulatory agencies have increased. At the same time the speed of recruitment is very slow, especially in academic studies which take an average of five months to get the first patient, while pharmaceutical studies take an average of three months, but in both cases there is room for improvement. Given that paediatric cancers are minority diseases, one of the ways to reduce times would be greater international collaboration and to make it easier for patients to travel to receive treatment in centres of reference.

Another problem that has been detected is that despite leukaemia being the most prevalent cancer in children, there are twice as many trials dedicated to solid tumours than to this pathology. This trend has been maintained throughout the entire period analysed. The research team hopes that once the gap is established, future work will focus on this cancer to reverse it.

"This analysis shows for the first time the paradigm shift with phase 1 and 2 clinical trials in paediatric cancer, with new, more efficient designs, which will achieve faster results and be more beneficial for patients and their families. Through the trials we will improve the survival and quality of life of children and adolescents with cancer", says Dr. Lucas Moreno, head of the Paediatric Oncology and Haematology Department at Vall d'Hebron University Hospital and head of the Childhood Cancer and Blood Disorders group at Vall d'Hebron Research Institute (VHIR).