The Prader-Willi Syndrome Clinical Trials Consortium (PWS-CTC) was created in 2015 to address challenges and accelerate clinical trials for PWS. Key challenges include better understanding the progression of the disease (or natural history), developing meaningful outcome measures of drug efficacy and incorporating the patient and caregiver voices into the decision-making process. The PWS-CTC is a pre-competitive, international and collaborative consortium gathering stakeholders from pharmaceutical companies, academia and PWS patient organizations (IPWSO, FPWR, PWSA-USA, PWS France).
A major focus of the PWS-CTC is to include the PWS caregiver perspectives and patient perspectives into the development of new therapies for PWS. We believe the voice of the patient community is critical to understanding the unmet medical needs of this population, establishing priorities and value assessments, and framing the benefit-risk analysis of new drugs.
Two exciting projects are being launched by PWS-CTC to gather the views of caregivers on how PWS impacts their lives and how they weigh the benefits and risks of new treatments for their loved ones. The findings of two new surveys - The Impact of PWS Symptoms on Caregivers and the Treatment Preferences in PWS - will guide pharmaceutical companies, regulatory agencies (FDA) and insurance companies in addressing the needs of the PWS community. We hope everyone in the PWS community will participate in both surveys so that the findings will be truly representative of the range of perspectives in our patient community.
Survey 1: Impact of PWS Symptoms on Caregivers
Last year, I participated in a PWS-CTC working group with Evan Farrar of PWSA-USA and Theresa Strong and Nathalie Kayadjanian of FPWR. We performed a study to measure the levels of burden in caregivers of individuals with PWS. We used the Zarit Burden Interview (ZBI), a tool that was originally developed by Professor Zarit (Penn State U.) to assess the burden of caregiving for individuals with Alzheimer`s disease. The ZBI is now widely used to measure the burden of caring for individuals with a disability or chronic illness, but had not been used in PWS. This initial study analyzed the responses from 142 caregivers.
We found impressively high levels of caregiver burden in PWS. The levels of burden increased as individuals with PWS age, reaching a peak during the teenage and young adult years. In addition, we found that the burden of PWS adversely affected marriage or romantic relationships, caregiver’s ability to work, caregiver`s sleep and mood (both anxiety and depressed mood). Interestingly, we also showed that the ZBI is a good predictor of PWS impact on caregiver`s quality of life.
Managing the burden of caring for a person with PWS
These findings draw attention to the critical unmet need of caregivers of individuals with PWS
Given how challenging PWS can be, it is important to consider what caregivers can do now to help buffer themselves or their partner from some of these difficult impacts. One important fact to recognize from the study is that caring for a person with PWS is really hard. It is important to remind yourself, as a caregiver and parent, that it is not about you doing something wrong or constantly needing to brush up on your parenting and behavior management skills. This parenting experience can be really intense and difficult no matter how fantastic you are as a parent.
It is also important to have a low bar for seeking out help and support; if you are struggling with frequent low mood and/or feelings of anxiety, talk to someone and get support. This could be a good friend, another special needs parent or a therapist. Each state has a chapter of the American Psychological Association. You can call your state chapter and they will provide a list of licensed therapists. Additionally, it is helpful to consider strategies to buffer against possible depression, anxiety or relationship difficulties by using active coping strategies. These could include exercise, engaging with other special needs parents, making special time for your relationship with your partner and getting involved in a meaningful activity, for example participate in a patient advocacy group, advocate for people with disabilities in your local school system, educate others about your child’s condition or something else to help you feel engaged. No matter how big or small this effort is it can be a very helpful way to cope with mood challenges and isolation that are common in caregivers.
Lastly, make sleep a priority for you, the caregiver. We found that a high percentage (60%) of caregivers report ongoing disrupted sleep due to their child with PWS. There is a long line of research showing that improving sleep can also improve mood and overall physical health.
Unfortunately none of the above strategies are likely to directly treat the symptoms of PWS or solve any particular struggle your child is having, but doing some of these things to take care of yourself and cope with the challenges can help you, the caregiver, to go further to assist your child, with PWS with renewed energy, strength, and perspective.
You can watch the caregiver burden webinar for more details on the study and additional coping suggestions.
Incorporating measures of caregiver burden in future PWS clinical trials
The results of this study drew the interest of our industry partners to incorporate the ZBI as an exploratory outcome measure in clinical trials for individuals with PWS. The underlying assumption is that a new drug that would improve the health of individuals with PWS would also reduce the burden on caregivers. Several questions, however, need to be addressed before caregiver burden measurement can be tested as a part of future clinical trials. These include:
- How does caregiver burden vary over time?
- What aspects of PWS contribute to the caregiver burden?
- Is there a relationship between caregiver burden and hyperphagia (excessive hunger)?
To address these questions, we've recently launched a new survey, The Impact of PWS Symptoms on Caregivers. The results of this survey will help our industry partners determine how useful it would be to incorporate the ZBI as an exploratory trial endpoint.
Survey 2: Caregiver Perspectives on Treatment Preferences in PWS
The second survey (open to parents/caregivers of those with PWS, age 4+) addresses the caregivers perspective on risk versus benefit in considering new drugs. As part of the drug approval process, the FDA considers a structured Benefit-Risk Assessment to weigh the possible benefits of a drug compared to the risks (eg, possible side effects). This is considered in the context of the severity of symptoms and unmet medical needs of the target population. The FDA is committed to considering the patient perspective in the benefit risk assessment, a commitment that has been further strengthened by the recent passage of the 21st Century Cures Act. The PWS CTC is seeking to inform the FDA Benefit-Risk assessment for potential PWS treatments by documenting the patient perspective on the need for treatments to improve PWS symptoms, and the level of risk that families are willing to accept (eg, what risk of side effects would be acceptable for a drug that is effective).
Dr. John Bridges at Johns Hopkins University is a pioneer in this area of research, and has worked collaboratively with many patient communities to provide the patient perspective on drug development. He and his team have been working with the PWS-CTC and a PWS Community Advisory Board for the last year to develop an online assessment to capture the diversity of perceptions in the PWS community on treatment needs and risk tolerance. They are now launching a broad national survey, and are asking primary caregivers to complete this Treatment Preferences survey. The results will be shared with the FDA, the PWS community and other stakeholders, and will provide important guidance on the needs of our loved ones with PWS.
We are fortunate in the PWS community to have potential new therapies in the pipeline that might improve some of the most challenging aspects of PWS. By taking the time to complete both surveys, you will ensure that that PWS-CTC has the necessary, rigorous evidence in hand to facilitate the evaluation of drugs that will be meaningful for our loved ones with PWS. The evidence generated will form a strong foundation upon which regulatory agencies can make drug approval decisions, and insurance companies can consider drug reimbursement decisions. Please make sure your voice is heard!