An Open-Label Study of Trofinetide for the Treatment of Girls Two to Five Years of Age Who Have Rett Syndrome (DAFFODIL™)
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The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. |
ClinicalTrials.gov Identifier: NCT04988867 |
Recruitment Status :
Active, not recruiting
First Posted : August 4, 2021
Last Update Posted : May 6, 2022
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Condition or disease | Intervention/treatment | Phase |
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Rett Syndrome | Drug: Trofinetide | Phase 2 Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 15 participants |
Allocation: | N/A |
Intervention Model: | Single Group Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | An Open-Label Study of Trofinetide for the Treatment of Girls Two to Five Years of Age Who Have Rett Syndrome |
Actual Study Start Date : | September 22, 2021 |
Estimated Primary Completion Date : | July 2023 |
Estimated Study Completion Date : | July 2023 |

Arm | Intervention/treatment |
---|---|
Experimental: Drug - trofinetide
Oral dose of trofinetide
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Drug: Trofinetide
Trofinetide solution of 10-30 mL based on subject's weight at Baseline, administered twice daily by mouth or gastrostomy tube (G-tube) |
- Safety and tolerability of treatment with oral trofinetide [ Time Frame: Approximately 24 Months Treatment Duration ]Percentage of subjects with Treatment-emergent adverse events (TEAEs), serious adverse events (SAEs), withdrawals due to AEs, potentially clinically important changes in other safety assessments
- Whole blood concentration of oral trofinetide [ Time Frame: Pre-dose and Weeks 2, 4, 8, and 12 ]
- Area under the plasma concentration-time curve (AUC) [ Time Frame: Pre-dose and Weeks 2, 4, 8, and 12 ]
- Maximum (peak) observed drug concentration (Cmax) [ Time Frame: Pre-dose and Weeks 2, 4, 8, and 12 ]
- Apparent terminal elimination half-life (t½) [ Time Frame: Pre-dose and Weeks 2, 4, 8, and 12 ]

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Ages Eligible for Study: | 2 Years to 5 Years (Child) |
Sexes Eligible for Study: | Female |
Gender Based Eligibility: | Yes |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
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Female subject
- 2 to 4 years of age and body weight ≥9 kg and <20 kg at Screening OR
- 5 years of age and body weight ≥9 kg and <12 kg at Screening
- Can swallow the study medication provided as a liquid solution or can take it by gastrostomy tube
- The subject's caregiver is English-speaking and has sufficient language skills to complete the caregiver assessments
- Has classic/typical Rett syndrome (RTT) or possible RTT according to the Rett Syndrome Diagnostic Criteria
- Has a documented disease-causing mutation in the MECP2 gene
- Has a stable pattern of seizures, or has had no seizures, within 8 weeks prior to Screening
- Subject and caregiver(s) must reside at a location to which study drug can be delivered and have been at their present residence for at least 4 weeks prior to Screening
Exclusion Criteria:
- Has been treated with insulin within 12 weeks of Baseline
- Has current clinically significant cardiovascular, endocrine (such as hypo- or hyperthyroidism, Type 1 diabetes mellitus, or uncontrolled Type 2 diabetes mellitus), renal, hepatic, respiratory or gastrointestinal disease (such as celiac disease or inflammatory bowel disease) or has major surgery planned during the study
- Has a history of, or current, cerebrovascular disease or brain trauma
- Has significant, uncorrected visual or uncorrected hearing impairment
- Has a history of, or current, malignancy
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Has any of the following:
- QTcF interval of >450 ms at Screening or Baseline
- History of a risk factor for torsades de pointes (e.g., heart failure or family history of long QT syndrome)
- History of clinically significant QT prolongation that is deemed to put the subject at increased risk of clinically significant QT prolongation
- Other clinically significant finding on ECG at Screening or Baseline
Additional inclusion/exclusion criteria apply. Patients will be evaluated at baseline to ensure that all criteria for study participation are met. Patients may be excluded from the study based on these assessments (and specifically, if it is determined that their baseline health and condition do not meet all prespecified entry criteria).

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04988867
United States, Alabama | |
University of Alabama at Birmingham | |
Birmingham, Alabama, United States, 35233 | |
United States, Colorado | |
Children's Hospital Colorado | |
Aurora, Colorado, United States, 80045 | |
United States, Illinois | |
Rush University Medical Center | |
Chicago, Illinois, United States, 60612 | |
United States, Massachusetts | |
Boston Children's Hospital/Harvard Medical School | |
Boston, Massachusetts, United States, 02115 | |
United States, Minnesota | |
Gillette Children's Hospital | |
Saint Paul, Minnesota, United States, 55101 | |
United States, Missouri | |
Washington University | |
Saint Louis, Missouri, United States, 63110 | |
United States, Tennessee | |
Vanderbilt University Medical Center | |
Nashville, Tennessee, United States, 37232 |
Responsible Party: | ACADIA Pharmaceuticals Inc. |
ClinicalTrials.gov Identifier: | NCT04988867 |
Other Study ID Numbers: |
ACP-2566-009 |
First Posted: | August 4, 2021 Key Record Dates |
Last Update Posted: | May 6, 2022 |
Last Verified: | May 2022 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Rett Syndrome Syndrome Disease Pathologic Processes Mental Retardation, X-Linked Intellectual Disability |
Neurobehavioral Manifestations Neurologic Manifestations Nervous System Diseases Genetic Diseases, X-Linked Genetic Diseases, Inborn Heredodegenerative Disorders, Nervous System |