HD Patients Prefer Less Invasive, No-Placebo Gene Therapy Trials, Survey Says

Eligible Huntington’s disease patients would likely participate in a gene therapy trial regardless of the study design, but they are more inclined toward those with less invasive interventions and without a placebo group, a questionnaire-based study suggests.

The results may be useful to design more patient-centered clinical trials assessing the effects of gene therapy in Huntington’s patients.

The study, “Attitudes of Potential Participants Towards Molecular Therapy Trials in Huntington’s Disease,” was published in the Journal of Huntington’s Disease.

While a new therapy might face obstacles to its development during clinical trials, a significant proportion of studies fail because of the complexity of patient recruitment and lack of patient participation.

There is a growing effort to incorporate the patient perspective into clinical trial design in order to develop studies that better integrate patients’ needs and preferences.

With the development of new gene or molecular therapies to halt or prevent the development of Huntington’s disease — mainly administered through more invasive procedures — it is important to understand patients’ concerns and willingness to participate in these trials.

“In order to optimize feasibility [of clinical trials], it is important to first understand how potential study participants feel about these new trial designs, with interventions that might involve a higher potential risk but also higher potential reward,” Tanya M. Bardakjian, the study’s first author and a senior genetic counselor in the Department of Neurology at Perelman School of Medicine at the University of Pennsylvania, said in a press release.

Researchers at Penn designed a questionnaire to evaluate how patient clinical status, study design, and therapy goals can influence the willingness of eligible Huntington’s patients to participate in gene therapy trials.

The anonymous survey was distributed through the Huntington’s Disease Society of America website. It mainly consisted of multiple-choice questions and scale responses involving hypothetical scenarios based on current or future therapeutic interventions for Huntington’s disease.

Such interventions included therapy administered through pills, directly into the bloodstream, through the spinal cord, or directly into the brain. The survey also involved a scenario where the clinical trial had a placebo group.

Researchers collected the demographic, clinical, and genetic data of 87 people who responded to the survey and classified them according to disease stage: 36 had been diagnosed with Huntington’s disease, 18 were pre-symptomatic carriers of Huntington’s mutations, and 33 had no symptoms but were at risk of developing the condition. Respondents had a mean age of 46.9 years and were highly educated.

Most respondents reported they would be likely or very likely to participate in clinical trials, regardless of study design or therapy goal. However, all three groups showed a more favorable attitude toward clinical studies with less invasive and frequent therapies, and those without a placebo.

Researchers suggested that giving patients the option to receive the experimental therapy once the placebo period ends may help counteract the negative effect of having a placebo group within a trial.

Participants who knew they carried Huntington’s mutation and would eventually develop the disease were significantly more positive toward participation in clinical trials, except those with higher risk or lower benefit.

The results also showed that participants had a positive view of the motivations that drive the investigators who conduct these trials, believing they work for the patients’ benefit over their own personal or professional gain.

Despite the study’s limitations, such as a small sample size with highly educated participants, researchers say their findings likely reflect the global opinion of Huntington’s patients.

“We believe that a patient-centered trial design, through the inclusion of appropriate education and communication to ensure participants and advocates are informed and engaged, is likely to have a positive impact on recruitment,” Bardakjian said.

The study was supported by a grant from the Precise Medicine Special Interest group of the National Society of Genetic Counselors.