Drug development in pediatric oncology – challenges and opportunities – reflections from European regulators

Strategies to facilitate adolescent access to medicines: Improving regulatory guidance

BACKGROUND

Historically, pediatric medicines are developed after adult trials are completed, even when identical drug targets and disease similarities exist across the populations. This has resulted in significant delays in the authorization of medicines for adolescent use, limiting access to beneficial drugs. This study sought to understand how adolescent inclusion in adult trials is positioned in regulatory guidance documents as they set critical expectations for trial design and regulatory decision-making.

METHODS

This study utilized a qualitative analysis approach. Guidance documents were identified via Food and Drug Administration and European Medicines Agency websites. Utilizing a blinded adjudication process, the documents were classified as permissive, exclusionary, or silent regarding recommendations about adolescent inclusion in adult clinical trials. A post hoc analysis of similarities and differences between the Food and Drug Administration and European Medicines Agency guidance documents was conducted to assess the possible role of regional pediatric research laws on age-inclusive trial methodologies as well as emergent themes by therapeutic area.

RESULTS

In total, 96 Food and Drug Administration (1977 to 2019) and 106 European Medicines Agency (1987 to 2019) guidance documents were identified for analysis. The guidance contained explicit or implicit recommendations supporting adolescent inclusion in adult trials in 32% of Food and Drug Administration and 15% of European Medicines Agency documents, while 14% and 21%, respectively, were found to be exclusionary. A large number of guidance documents were silent regarding the applicability of adolescent-inclusive trial designs (53% and 64%, Food and Drug Administration and European Medicines Agency, respectively). Analysis by therapeutic area revealed the most permissive of adolescent inclusion in Food and Drug Administration guidance for infectious diseases and conditions requiring blood products in European Medicines Agency guidance. A more holistic approach to age-inclusive trial design was identified in disease guidance published by the Food and Drug Administration Oncology Center of Excellence.

DISCUSSION

There are many influences on the development and/or revision of regulatory guidance documents. Substantial scientific knowledge and regulatory precedence for the inclusion of adolescents within adult trials are available to inform research approaches. Our study has identified important opportunities for the enhancement of guidance. For example, contextualization of developmental factors influencing adolescent disease progression provides insights into the role of adolescent inclusion. If addressed, guidance documents can facilitate broader acceptance of age-inclusive trial methodologies and accelerate adolescent access to medicines.

ACCELERATE and European Medicine Agency Paediatric Strategy Forum for medicinal product development for mature B-cell malignancies in children

Paediatric Strategy Forums have been created by the multistakeholder organisation, ACCELERATE, and the European Medicines Agency to facilitate dialogue between all relevant stakeholders and suggest strategies in critical areas of paediatric oncology drug development. As there are many medicines being developed for B-cell malignancies in adults but comparatively few in children with these malignancies, a Paediatric Strategy Forum was held to discuss the best approach to develop these products for children. It was concluded that as current frontline therapy is highly successful, despite associated acute toxicity, de-escalation of this or substitution of presently used drugs with new medicines can only be undertaken when there is an effective salvage regimen, which is currently not available. Therefore priority should be given to developing treatment for patients with relapsed and refractory mature B-cell lymphomas. The consensus of the clinicians attending the meeting was that CAR T-cells, T-cell engagers and antibody drug conjugates (excluding those with a vinca alkaloid-like drug) presently have the greatest probability of providing benefit in relapse in view of their mechanism of action. However, as producing autologous CAR T-cells currently takes at least 4 weeks, they are not products which could be quickly employed initially at relapse in rapidly progressing mature B-cell malignancies but only for the consolidation phase of the treatment. Global, industry-supported, academic-sponsored studies testing compounds from different pharmaceutical companies simultaneously should be considered in rare populations, and it was proposed that an international working group be formed to develop an overarching clinical trials strategy for these disease groups. Future Forums are planned for other relevant paediatric oncologic diseases with a high unmet medical need and relevant molecular targets.