Clinical Research Trends for Rare Diseases in Spain: 2025 Analysis

The landscape of clinical research for rare diseases in Spain continues to evolve, reflecting a sustained commitment to innovation and therapeutic development. According to the Informe sobre Ensayos Clínicos para Enfermedades Raras en España 2025, published by the Asociación Española de Laboratorios de Medicamentos Huérfanos y Ultrahuérfanos (Aelmhu), the sector has demonstrated resilience and growth, maintaining its importance within the national clinical trial framework.

Key Findings in Rare Disease Research

Data from the Spanish Registry of Clinical Studies (REec) of the Spanish Agency of Medicines and Medical Devices (Aemps) indicates that 962 clinical trials were authorized in Spain during 2025. Of these, 216 were specifically targeted at rare diseases. This represents 22% of all clinical research activity, marking a 4% increase in rare disease-specific trials compared to the previous year.

The research ecosystem also saw an expansion in patient engagement, with an 11% increase in the number of participants enrolled in these studies, totaling 4,088 individuals. The pharmaceutical industry remains the primary driver of this activity, accounting for 98% of all authorized investigations in this field, with a total of 212 industry-sponsored studies in 2025.

Geographic Distribution of Research

Research activity is not uniform across the country. Catalonia, the Community of Madrid and Andalusia emerged as the regions with the highest volume of activity, collectively hosting more than 50% of the rare disease studies conducted in 2025. Specifically, Catalonia led with 171 trials, followed by Madrid (151), Andalusia (100), and the Valencian Community (79). However, when adjusted for population density, regions such as Navarre, Galicia, and the Basque Country demonstrate a high rate of clinical trial activity per million inhabitants.

Therapeutic Focus and Clinical Phases

Clinical trials for rare conditions are predominantly concentrated in the later stages of development, with 72% of studies falling under phases II and III. Notably, phase III trials experienced a significant uptick, growing by 22% compared to 2024, rising from 77 to 94 authorized studies.

While oncology remains the leading area of research with 47 clinical trials, its relative dominance has shifted, accounting for 22% of the total—a four-percentage-point decrease from the previous year. Other therapeutic areas have seen substantial growth:

• Immune System: 44 trials, reflecting a 38% increase.
• Nervous System: 33 authorized trials.
• Congenital, Hereditary, and Neonatal conditions: 27 trials.
• Cardiovascular Rare Diseases: 16 trials, effectively doubling the figures from the previous year.

The Role of Advanced Therapies

Advanced therapy medicinal products (ATMPs) remain a critical, albeit fluctuating, pillar of rare disease research. In 2025, the total number of authorized studies involving advanced therapies saw a 25% decline, with a more pronounced 64% decrease specifically within the rare disease category, dropping from 28 to 10 trials. Despite this recent contraction, these therapies continue to be a primary focus for developing innovative, potentially curative treatments for patients with high unmet medical needs.

Six-Year Evolution (2020–2025)

A long-term view of the sector reveals a steady upward trajectory. Over the last six years, Spain has authorized 5,678 clinical trials, with 1,284—or 23%—dedicated to rare diseases. This sustained output, averaging approximately 200 studies annually, underscores the strategic importance of this field. Throughout this period, the pharmaceutical industry has been the engine of this growth, promoting 1,236 of the 1,284 rare disease trials authorized since 2020.

Expert Outlook

Beatriz Perales, president of Aelmhu, notes that these figures confirm the ongoing consolidation of rare disease research in Spain. While the data highlights the pharmaceutical industry’s firm commitment to innovation, industry leaders emphasize the need for continued administrative streamlining and robust R&D incentives to maintain Spain’s competitive edge in the global clinical research market and to expedite the delivery of new therapeutic alternatives to patients.

Key Takeaways

• Steady Growth: Rare disease trials now represent 22% of all clinical research in Spain.
• Industry-Led: 98% of rare disease research is sponsored by the pharmaceutical industry.
• Diversification: While oncology leads, there is significant growth in immunology, neurology, and cardiovascular research.
• Regional Activity: Catalonia, Madrid, and Andalusia are the primary hubs, though smaller regions show high per-capita research rates.