Medicines are often tested in highly controlled environments during clinical trials aimed at rapid development and thorough assessment of their benefits and risks, with key efficacy and safety aspects evaluated for regulatory approval. However, important questions regarding the optimisation of medicines' use in clinical practice may remain unanswered at the time of marketing authorisation, notably those related to the optimal dose, duration, schedule, sequence, and combination of treatments. This knowledge gap is particularly critical in oncology, where patient quality of life must be prioritised, and there is the pressing need to understand the most efficient use of costly innovative therapies in the context of rising cancer incidence and prevalence. Addressing these challenges requires multi-stakeholder collaboration. Organisations within the Cancer Medicines Forum (CMF), co-chaired by the European Organisation for Research and Treatment of Cancer and the European Medicines Agency, have advocated for policy actions promoting treatment optimisation research within the European Union. To advance this objective, the CMF convened a multidisciplinary stakeholder workshop, offering a platform for collaborative dialogue by bringing together experts from governmental bodies, regulatory agencies, health technology assessment bodies, patient organisations, academia, learned societies, industry, public health organisations, clinicians, and investigators. This workshop aimed to examine existing barriers and explore strategies to integrate treatment optimisation into the current cancer clinical research framework, ultimately providing key recommendations, summarised in this review, to systematically embed treatment optimisation in oncology research.

Dysimmune inflammatory neuropathies (DINs), including Guillain-Barré syndrome (GBS), chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), and multifocal motor neuropathy (MMN), are rare immune-mediated disorders of the peripheral nervous system associated with substantial diagnostic, therapeutic, functional, psychosocial, and policy-related unmet needs. This narrative review synthesises published evidence, clinical guidance, and patient-perspective inputs to characterise the European DIN patient pathway and identify priorities for improved care. The review highlights persistent challenges in early recognition, differential diagnosis, timely treatment initiation, long-term immunoglobulin use optimisation, rehabilitation, outcome measurement, and patient engagement. It also identifies important inequities in access to immunoglobulin therapy and emerging treatments, driven by plasma supply constraints, heterogeneous reimbursement criteria, affordability barriers, and inconsistent implementation of evidence-based care. Addressing these gaps will require harmonised DIN care pathways, systematic use of patient-reported outcomes, integrated rehabilitation, strengthened plasma supply resilience, real-world evidence generation, and structured patient involvement in clinical, regulatory, reimbursement, and policy processes. A coordinated European approach could improve outcomes for patients with DINs and provide a model for patient-centred policy reform in rare neurological diseases.