The L16HTHOUSE Study

L16HTHOUSE is a research trial testing an experimental medication for treating speech, motor, learning, and other developmental delays in children and adolescents with 16p11.2 deletion syndrome.

See if Your Child Qualifies

The L16HTHOUSE Study

L16HTHOUSE is a research trial testing an experimental medication for treating speech, motor, learning, and other developmental delays in children and adolescents with 16p11.2 deletion syndrome.

See if Your Child Qualifies

Learn More Below

The Study

The 16p11.2 deletion

Chromosome16p11.2 deletion is a condition where a small portion of one copy of chromosome 16 is missing. Most cases occur in individuals without a family history of the deletion, but some cases are inherited and more than one family member is affected. Signs and symptoms may vary greatly, even among affected members of the same family.

Research has shown that the chromosome16p11.2 deletion can be associated with developmental impairment in many areas, including speech and language, learning and memory, motor skills, and autistic symptoms. Almost all children with the 16p deletion show some developmental delays, and these delays and impairments often persist into adolescence and adulthood. Currently, there is no medication available for treatment of 16p11.2 deletion syndrome.

The Study Medication

The L16HTHOUSE Study is underway to evaluate the safety, tolerability, and effectiveness of a new investigational medication, called arbaclofen. Arbaclofen is closely related to an FDA-approved medication, baclofen, that has been safely prescribed to children and adults for many years. The study is being conducted to see if arbaclofen may help with the developmental impairments in children and adolescents with the 16p11.2 deletion. The L16HTHOUSE study is sponsored by Clinical Research Associates (CRA), an affiliate of the Simons Foundation.

Arbaclofen, the study medication, has been found to be generally well-tolerated in previous research trials in children with autism spectrum disorder (ASD) and Fragile X syndrome. Results were not conclusive, but suggest that arbaclofen may improve some symptoms of ASD.

Study Participation​

In the L16HTHOUSE study, children, 5-17 years old, with the 16p11.2 deletion will take study medication for up to 16 weeks. Including screening evaluations and follow-up, the total duration of a child’s participation will be less than 28 weeks. If the participant completes all study requirements through Visit 4 (Close-out Visit), he/she may be eligible for an optional “open-label” study with arbaclofen. Each participant will be evaluated for multiple aspects of development, including speech, memory, learning, motor skills, and social functioning. These evaluations will be performed before, during, and after the treatment period at a highly experienced research center. The study participant will need to travel to the research center 4 or 5 times during the study, and must be accompanied by the same person (parent or caregiver) at each visit. 

Each participant will be randomized to take either the study medication (arbaclofen) or placebo during the trial. A placebo is a pill that looks just like the study medication, but contains no active ingredients. The placebo in this trial will be in the form of an oral disintegrating tablet, identical to active study medication. The randomization is 1:1, meaning there is a 50:50 chance (like flipping a coin) that each participant will receive the actual arbaclofen. No one will know whether a participant is taking arbaclofen or placebo. Every participant will be treated the same, and will undergo the same evaluations. After completion of this placebo-controlled study, a participant may be invited to participate in another study, during which all participants will receive arbaclofen and no one will receive placebo.

Study participants will receive medical evaluations, study-related medical care, extensive developmental testing, and study medication at no cost. All travel for the study, including airline and car travel, meals, and reimbursement for your time, will be arranged and paid for by CRA.

Participation in the study is entirely voluntary.

Eligibility for the study will be assessed by the study staff at the research center.

Research Centers

The L16HTHOUSE study is being conducted at a small number of medical centers that are very experienced with the 16p11.2 deletion. Travel to and from the study appointments can be arranged and paid for by the study, even if the research center is far away. If your family has previously participated in research at one of the centers, we recommend that you participate at that center again. 

If you would like to see if your family member might be eligible, please select one of the research centers from the map.

Center for Autism and the Developing Brain

21 Bloomingdale Road, White Plains, NY 10605

Research Centers

Center for Autism and the Developing Brain

21 Bloomingdale Road, White Plains, NY 10605

The L16HTHOUSE study is being conducted at a small number of medical centers that are very experienced with the 16p11.2 deletion. Travel to and from the study appointments can be arranged and paid for by the study, even if the research center is far away. If your family has previously participated in research at one of the centers, we recommend that you participate at that center again. 

If you would like to see if your family member might be eligible, please select one of the research centers from the map.

About Clinical Research

A clinical drug study, also referred to as a research study, clinical trial, clinical study, or drug trial, is conducted to learn whether a drug, treatment, or method is safe and effective for people who have certain conditions, ailments or illnesses. 

Research helps answer specific questions about a medicine, drug or treatment, such as:

  • Is it effective??
  • Is it more effective than another established treatment?
  • Is it safe?
  • What are the potential side effects? 

Many people around the world participate in clinical drug studies every year. By participating in this type of study, you will be contributing to advancements that could help future families. 

Only you can decide if a clinical study is right for your loved one. You should only make your decision after you have learned about the study, have had all your questions answered, and have been thoroughly informed about the risks and possible benefits. 

Participating in a clinical study is totally voluntary. If you decide to enroll your family member in this study — or any clinical drug study — you are free to withdraw them at any time and for any reason. 

More information about clinical research is available from the American Academy of Pediatrics and from the National Institutes of Health.