DAYBUE may help open up more possibilities

DAYBUE is the first and only FDA-approved treatment shown to improve signs and symptoms of Rett syndrome in adults and children 2 years and older.

It's available in 2 formulations: DAYBUE and DAYBUE^® STIX—so you can choose the option that best fits your family's needs.

DAYBUE is not a cure for Rett syndrome. It is not known if DAYBUE is safe and effective in children under 2 years of age.

How was DAYBUE studied?

Caregivers and doctors played a key role in evaluating DAYBUE during the LAVENDER™ study

Doctors evaluated if patients improved or got worse, while caregivers looked for changes in the symptoms of Rett syndrome. See the results from the clinical study below.

Caregivers used the Rett Syndrome Behaviour Questionnaire (RSBQ) to evaluate changes in the signs and symptoms of Rett syndrome.

Doctors used the Clinical Global Impression-Improvement (CGI-I) scale to evaluate if Rett symptoms had improved or worsened.

Study design

The effectiveness and safety of DAYBUE were evaluated in the 12-week LAVENDER clinical study of 187 female patients aged 5 to 20 with Rett syndrome

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Breathing

Hand movements or stereotypies

Repetitive behaviors

Nighttime behaviors

Vocalizations

Facial expressions

Eye gaze

Mood

Caregivers evaluated 45 items on the RSBQ. Each item was scored as not true (0), somewhat or sometimes true (1), or very true or often true (2)
These scores were added together to create the RSBQ total score
Researchers looked at the change in average RSBQ total score from the start of the study to measure how DAYBUE impacted the symptoms of Rett at Week 12 when compared to patients receiving placebo

At 12 weeks, caregivers observed:

Significant improvements in the symptoms of Rett syndrome as measured by average change in RSBQ total score with DAYBUE vs placebo

At 12 weeks, the group of patients receiving DAYBUE (n=76) saw a decrease of 4.9 in average RSBQ total score from the start of the study when compared with a decrease of 1.7 in the placebo group (n=85), meaning an improvement in Rett symptoms
The difference between the 2 groups was -3.2. A lower score meant symptoms of Rett syndrome were less severe
Before starting treatment, the average RSBQ total score for the DAYBUE group was 43.7. For the placebo group, the average RSBQ total score before treatment was 44.5
Results varied between patients in the clinical study. The effect of DAYBUE on individual symptoms measured by RSBQ has not been shown. Individual results may vary with DAYBUE

Symptom areas (RSBQ)	Quinn6 years old Taking DAYBUE since 2021	Clare9 years old Taking DAYBUE since 2021	Kate9 years old Taking DAYBUE since 2021	Maddy21 years old Taking DAYBUE since 2020	Caitlin25 years old Taking DAYBUE since 2023

Hand movements or stereotypies	More control of hands. Can hold objects longer. Not grasping her body and face as much	Hands are more fluid and open, can hold a fork or cup, taps on fridge when hungry	More purposeful hand use. Able to use a spoon and point at and touch her tablet	Less aggressive hand movements. A little more control of hands	Hands have been more relaxed and has more control over them
Repetitive behaviors	Teeth grinding much improved			Hardly grinds her teeth anymore
Breathing	Less frequent breath holding and less hyperventilating			Fewer “blue spells” (breath holding)	Holds her breath less often. Before DAYBUE, was holding her breath on and off throughout the day
Nighttime behaviors		Less frequent night terrors allow her to sleep better		Fewer night terrors and laughing spells - now family gets more sleep
Vocalizations		Increased nonverbal vocalizations, able to let people know when she wants something		No words, but makes more sounds to respond	More purposeful
Facial expressions				Doesn't stick her tongue out as often	Increase in facial expressions. She looks at people when they are talking to her and smiles more
Eye gaze	Can hold her gaze to participate and engage, especially in the classroom	Uses eye gaze more to convey feelings, needs, and wishes. Allows her to show family what she wants for a snack	Able to use her eye-gaze device better to convey wishes	Makes choices more quickly with her eyes. More of an interest in using her eye-gaze device	Makes eye contact consistently; indicates she is listening to people by looking at them
Mood	Her moods are more predictable and cries a lot less	Less screaming and tantrums. Able to take an interest in the things around her	More peaceful at home, in school, and in groups	Mood is better, happier, much less crying for no apparent reason	Appears happier and has been laughing more with us

Important Notes:

In the clinical study, individual response varied. Some patients had minimal to no improvements with DAYBUE
These patients were also receiving other types of therapy, like physical, occupational, or speech therapy
Some of these patients experienced side effects, including diarrhea, behavioral issues, or gas. See the full stories to learn more about their DAYBUE experiences
Always speak with a healthcare provider to learn what to expect when starting DAYBUE or DAYBUE STIX, including side effects
The families featured here were compensated for sharing their stories and participating in photo shoots. These stories were created in 2024 and 2026

Clare, age 9, living with Rett syndrome, with her mom

Learn from caregivers and their individual loved one’s experience with DAYBUE

View DAYBUE stories

Clare, age 9, on DAYBUE since 2021, with her mom

At 12 weeks, doctors observed:

Significant improvements in the signs and symptoms of Rett syndrome as measured by the CGI-I scale vs placebo

The CGI-I scale was used by doctors to evaluate improvement or worsening of Rett symptoms

38% of patients (n=77) had improvements in symptoms with DAYBUE vs 15% of patients (n=86) taking placebo
- Much improved (13% vs 5% for placebo), minimally improved (25% vs 10%)
61% of patients had no improvements in symptoms with DAYBUE vs 81% of patients taking placebo. Individual results may vary

Lara, Family Support Educator

Do you have questions about treatment with DAYBUE?

While treatment with DAYBUE is a decision you and your loved one's doctor can make, Family Support Educators can help answer your questions about Rett syndrome, comprehensive care, and connecting with other caregivers.

Get connected with a Family Support Educator

Lara, Family Support Educator

Diarrhea:

Diarrhea is a common side effect of DAYBUE or DAYBUE STIX that can sometimes be severe. Diarrhea may cause your loved one to lose too much water from their body (dehydration). Before starting treatment with DAYBUE or DAYBUE STIX, stop taking laxatives. Tell your doctor if your loved one has diarrhea while taking DAYBUE or DAYBUE STIX. Your doctor may ask you to increase the amount your loved one drinks or give antidiarrheal medicine as needed.

Vomiting:

Vomiting is a common side effect of DAYBUE or DAYBUE STIX. Sometimes vomit can get into your loved one's lungs (aspiration), which could cause an infection (aspiration pneumonia). Tell your doctor if your loved one has severe vomiting or if vomiting happens often.

Weight loss:

DAYBUE or DAYBUE STIX can cause weight loss. Tell your doctor if you notice your loved one is losing weight at any time during treatment with DAYBUE or DAYBUE STIX.

Common side effects in the 12-week LAVENDER trial

Learn how to help manage possible side effects

Management guidance

The DAYBUE Overview Brochure provides information about treatment with DAYBUE.

The DAYBUE^® Overview Brochure provides information about DAYBUE clinical study results, safety facts, caregiver experiences, and helpful treatment tips.

Download Overview Brochure

The DAYBUE Treatment Discussion Guide can help you prepare for a conversation with your loved one's doctor.

The DAYBUE Treatment Discussion Guide is a tool you can use to talk to your loved one's doctor about DAYBUE.

Download Treatment Discussion Guide

Support by your side

Acadia Connect^® is a patient and family support program that connects you and your family with educational support and resources throughout the DAYBUE treatment journey.

Call Acadia Connect at 1-844-737-2223, Monday to Friday, 8am to 8pm ET, to learn more about our individualized support program designed to help meet the needs of your loved one taking DAYBUE.

Learn how we can help

Joe, Acadia Family Support Educator making heart with hands.

Indication and Important Safety Information

What is DAYBUE or DAYBUE STIX (trofinetide)?

DAYBUE or DAYBUE STIX are prescription medicines used to treat Rett syndrome in adults and children 2 years of age and older. It is not known if DAYBUE or DAYBUE STIX is safe and effective in children under 2 years of age.

What are the possible side effects of DAYBUE or DAYBUE STIX?

Diarrhea: Diarrhea is a common side effect of DAYBUE or DAYBUE STIX that can sometimes be severe. Diarrhea may cause you to lose too much water from your body (dehydration). Before starting treatment with DAYBUE or DAYBUE STIX, stop taking laxatives. Tell your healthcare provider if you have diarrhea while taking DAYBUE or DAYBUE STIX. Your healthcare provider may ask you to increase the amount you drink or take antidiarrheal medicine as needed.
Vomiting: Vomiting is a common side effect of DAYBUE or DAYBUE STIX. Sometimes vomit can get into your lungs (aspiration), which could cause an infection (aspiration pneumonia). Tell your healthcare provider if you have severe vomiting or if vomiting happens often.
Weight loss: DAYBUE or DAYBUE STIX can cause weight loss. Tell your healthcare provider if you notice you are losing weight at any time during treatment with DAYBUE or DAYBUE STIX.
The most common side effects of DAYBUE or DAYBUE STIX include diarrhea and vomiting. Other side effects include fever, seizure, anxiety, decreased appetite, tiredness, and the common cold. These are not all the possible side effects of DAYBUE or DAYBUE STIX. Tell your healthcare provider if you have any side effects that bother you or do not go away.

What should I tell my healthcare provider before taking DAYBUE or DAYBUE STIX?

Before taking DAYBUE or DAYBUE STIX, tell your healthcare provider about all of your medical conditions, including if you:

have kidney problems.
are pregnant or plan to become pregnant. It is not known if DAYBUE or DAYBUE STIX will harm your unborn baby.
are breastfeeding or plan to breastfeed. It is not known if DAYBUE or DAYBUE STIX passes into your breast milk. Talk to your healthcare provider about the best way to feed your baby while taking DAYBUE or DAYBUE STIX.

Tell your healthcare provider about all of the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Taking DAYBUE or DAYBUE STIX with certain medicines may affect how the other medicines work and can cause serious side effects.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088. You can also call Acadia Pharmaceuticals Inc. at 1-844-4ACADIA (1-844-422-2342).

DAYBUE is available as an oral solution (200 mg/mL).

DAYBUE STIX for oral solution powder is available in 5,000 mg, 6,000 mg, and 8,000 mg packets.

The risk information provided here is not comprehensive. To learn more, talk with your healthcare provider and read the full Prescribing Information, including Patient Information, also available at DAYBUE.com.