The importance of caregivers’ perspectives when evaluating the effectiveness of potential therapies for Sanfilippo

17 May 2022

Clinical trials depend on outcome measurements to evaluate the effectiveness of potential therapies. Biomarkers, like key enzymes, genes, or other characteristics, are often used to measure a biological response to a treatment. Other clinical measurements, particularly cognitive assessments, are also used in clinical trials for Sanfilippo to see if a therapy improves physical and cognitive function. However, biomarkers and cognitive tests may not always correlate with a patient’s or caregiver’s perception of whether a treatment is providing meaningful benefit to their child, and other clinical outcome assessments (COAs) may be needed.

A recent study has collected data from caregivers of patients with Sanfilippo to support COAs that are more meaningful and relevant for patients and families. The research was led by a collaborative team involving the Cure Sanfilippo Foundation, parent advocates, researchers, clinicians, and pharmaceutical companies.

Caregivers involved in the study had children with Sanfilippo between 2 and 24 years of age and at various stages of disease progression. The first stage of the study was a focus group of 11 caregivers, and the second stage comprised 19 individual interviews with caregivers who were not involved in stage one. Participants reported on the impact of Sanfilippo, its symptoms, and unmet treatment needs. 

A unanimous challenge for all participants was their child’s ability to communicate, and for most, the need to treat communication challenges was seen as a significant unmet treatment need. Communication challenges also impacted other symptoms like pain - six participants noted that it could be difficult to interpret when their child is in pain or distress.

Mobility was also described as a very important symptom at all stages of the disease that heavily relies on caregiver support. 

Sleep was another challenge that arose in the study, for the child with Sanfilippo and the whole family. Four caregivers noted that even a small improvement in sleep, such as an extra hour a night, would significantly improve quality of life. Other symptoms discussed included eating/swallowing, behaviour, and adapting to new environments or routines.

These findings support a move to look beyond cognitive outcome measures in clinical trials to encompass assessment of other symptoms that impact significantly on quality of life for children and families.

Importantly, the study also looked at how well caregivers felt the currently used and available clinical outcome assessment tools captured these outcomes, particularly for communication, pain, sleep, and eating. The results show that while key assessments involving these symptoms are available and are useful, some refinements may be needed to ensure they more specifically reflect the symptoms and disease course experienced by children and families with Sanfilippo syndrome.

This study provides valuable data for clinical trial teams and regulatory bodies to consider when planning and assessing future clinical trials. Assessments of a potential therapeutic’s effectiveness should include not only biological and cognitive tests, but also evaluations related to the child’s and family’s quality of life.

BioMarin, Lysogene, Sobi and Orchard Therapeutics provided funding support to Cure Sanfilippo Foundation for the study. No funders were involved in data collection or primary analysis for the project.