The first and only
FDA-approved treatment
for Rett syndrome

Add more of her
sparkle to the world around them

Kate, age 9, living with
Rett syndrome (left) and
her parents (right)

Explore how DAYBUE was studied

Review LAVENDER™, the pivotal Phase 3 trial.1,3

See the study design

See proven efficacy data1

View results of changes in RSBQ total score and CGI-I score from baseline to Week 12.

Explore the data

Review safety and tolerability profile1

Review side effect information, including safety and tolerability data and potential management strategies.

View the safety profile

*Improvement in signs and symptoms of RTT (breathing, hand movements or stereotypies, repetitive behaviors, night-time behaviors, vocalizations, facial expressions, eye gaze, and mood) were evaluated in a 12-week study as measured by the mean change from baseline in RSBQ total score and CGI-I score vs placebo.1

Kate, age 9, living with Rett Syndrome, with her brother.

Questions about DAYBUE?

Our representatives are here with information on this first and only treatment for RTT.

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Learn about the symptoms of RTT and the impact they can have on individuals and their caregivers.

About Rett syndrome >

CGI-I=Clinical Global Impression-Improvement; RSBQ=Rett Syndrome Behaviour Questionnaire.

Important Safety Information and Indication

  • Warnings and Precautions

    • Diarrhea: In a 12-week study and in long-term studies, 85% of patients treated with DAYBUE experienced diarrhea. In those treated with DAYBUE, 49% either had persistent diarrhea or recurrence after resolution despite dose interruptions, reductions, or concomitant antidiarrheal therapy. Diarrhea severity was of mild or moderate severity in 96% of cases. In the 12-week study, antidiarrheal medication was used in 51% of patients treated with DAYBUE.

      Patients should stop taking laxatives before starting DAYBUE. If diarrhea occurs, patients should notify their healthcare provider, consider starting antidiarrheal treatment, and monitor hydration status and increase oral fluids, if needed. Interrupt, reduce dose, or discontinue DAYBUE if severe diarrhea occurs or if dehydration is suspected.

    • Weight Loss: In the 12-week study, 12% of patients treated with DAYBUE experienced weight loss of greater than 7% from baseline, compared to 4% of patients who received placebo. In long-term studies, 2.2% of patients discontinued treatment with DAYBUE due to weight loss. Monitor weight and interrupt, reduce dose, or discontinue DAYBUE if significant weight loss occurs.

  • Adverse Reactions: The common adverse reactions (≥5% for DAYBUE-treated patients and at least 2% greater than in placebo) reported in the 12-week study were diarrhea (82% vs 20%), vomiting (29% vs 12%), fever (9% vs 4%), seizure (9% vs 6%), anxiety (8% vs 1%), decreased appetite (8% vs 2%), fatigue (8% vs 2%), and nasopharyngitis (5% vs 1%).

  • Drug Interactions: Effect of DAYBUE on other Drugs

    • DAYBUE is a weak CYP3A4 inhibitor; therefore, plasma concentrations of CYP3A4 substrates may be increased if given concomitantly with DAYBUE. Closely monitor when DAYBUE is used in combination with orally administered CYP3A4 sensitive substrates for which a small change in substrate plasma concentration may lead to serious toxicities.

    • Plasma concentrations of OATP1B1 and OATP1B3 substrates may be increased if given concomitantly with DAYBUE. Avoid the concomitant use of DAYBUE with OATP1B1 and OATP1B3 substrates for which a small change in substrate plasma concentration may lead to serious toxicities.

  • Use in Specific Population: Renal Impairment

    • DAYBUE is not recommended for patients with moderate or severe renal impairment.

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

  • Indication

DAYBUE is indicated for the treatment of Rett syndrome in adults and pediatric patients 2 years of age and older.

Please read the full Prescribing Information.

Important Safety Information and Indication

  • Warnings and Precautions

    • Diarrhea: In a 12-week study and in long-term studies, 85% of patients treated with DAYBUE experienced diarrhea. In those treated with DAYBUE, 49% either had persistent diarrhea or recurrence after resolution despite dose interruptions, reductions, or concomitant antidiarrheal therapy. Diarrhea severity was of mild or moderate severity in 96% of cases. In the 12-week study, antidiarrheal medication was used in 51% of patients treated with DAYBUE.

      Patients should stop taking laxatives before starting DAYBUE. If diarrhea occurs, patients should notify their healthcare provider, consider starting antidiarrheal treatment, and monitor hydration status and increase oral fluids, if needed. Interrupt, reduce dose, or discontinue DAYBUE if severe diarrhea occurs or if dehydration is suspected.

    • Weight Loss: In the 12-week study, 12% of patients treated with DAYBUE experienced weight loss of greater than 7% from baseline, compared to 4% of patients who received placebo. In long-term studies, 2.2% of patients discontinued treatment with DAYBUE due to weight loss. Monitor weight and interrupt, reduce dose, or discontinue DAYBUE if significant weight loss occurs.

  • Adverse Reactions: The common adverse reactions (≥5% for DAYBUE-treated patients and at least 2% greater than in placebo) reported in the 12-week study were diarrhea (82% vs 20%), vomiting (29% vs 12%), fever (9% vs 4%), seizure (9% vs 6%), anxiety (8% vs 1%), decreased appetite (8% vs 2%), fatigue (8% vs 2%), and nasopharyngitis (5% vs 1%).

  • Drug Interactions: Effect of DAYBUE on other Drugs

    • DAYBUE is a weak CYP3A4 inhibitor; therefore, plasma concentrations of CYP3A4 substrates may be increased if given concomitantly with DAYBUE. Closely monitor when DAYBUE is used in combination with orally administered CYP3A4 sensitive substrates for which a small change in substrate plasma concentration may lead to serious toxicities.

    • Plasma concentrations of OATP1B1 and OATP1B3 substrates may be increased if given concomitantly with DAYBUE. Avoid the concomitant use of DAYBUE with OATP1B1 and OATP1B3 substrates for which a small change in substrate plasma concentration may lead to serious toxicities.

  • Use in Specific Population: Renal Impairment

    • DAYBUE is not recommended for patients with moderate or severe renal impairment.

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

  • Indication

DAYBUE is indicated for the treatment of Rett syndrome in adults and pediatric patients 2 years of age and older.

Please read the full Prescribing Information.

References: 1. Acadia Pharmaceuticals Inc. DAYBUE [Package Insert]. San Diego, CA, 2023. 2. Acadia Pharmaceuticals announces U.S. FDA approval of DAYBUE™ (trofinetide) for the treatment of Rett syndrome in adult and pediatric patients two years of age and older. [press release]. Acadia Pharmaceuticals Inc. March 10, 2023. 3. Neul JL, Percy AK, Benke TA, et al. Design and outcome measures of LAVENDER, a phase 3 study of trofinetide for Rett syndrome. Contemp Clin Trials. 2022;114:106704.

This website is intended for use by US healthcare professionals.

©2023 Acadia Pharmaceuticals Inc.
Acadia and Acadia Connect are registered trademarks and DAYBUE is a trademark of Acadia Pharmaceuticals Inc. All other trademarks are the property of their respective owners. All rights reserved.
DAY-0073-v3 11/23

Acadia is trailblazing breakthroughs in neuroscience to elevate life. For more than 25 years, we have been working at the forefront of healthcare to bring vital solutions to people who need them most.
12830 El Camino Real, Suite 400
San Diego, CA 92130

Acadia is trailblazing breakthroughs in neuroscience to elevate life. For more than 25 years, we have been working at the forefront of healthcare to bring vital solutions to people who need them most.
12830 El Camino Real, Suite 400
San Diego, CA 92130

©2023 Acadia Pharmaceuticals Inc.
Acadia and Acadia Connect are registered trademarks and DAYBUE is a trademark of Acadia Pharmaceuticals Inc. All other trademarks are the property of their respective owners. All rights reserved.
DAY-0073-v3 11/23

Welcome to the DAYBUE™ (trofinetide) website.

This information is intended for US healthcare professionals only.

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Using the RSBQ, caregivers were asked to score 45 symptoms of RTT on a scale from 0 (not true) to 2 (very/often true).1 The rating scale and items in the RSBQ are shown below.9

  • Hand movements are uniform and monotonous

  • Has difficulty in breaking/stopping hand stereotypies

  • There are times when breathing is deep and fast (hyperventilation)

  • There are times when breath is held

  • The amount of time spent looking at objects is longer than the time spent holding or manipulating them

  • Makes mouth grimaces

  • There are times when parts of the body are held rigid

  • Restricted repertoire of hand movements

  • Has wounds on hands as a result of repetitive hand movements

  • Makes grimacing expressions with face

  • Swallows air

  • Does not use hands for purposeful grasping

  • Tendency to bring hands together in front of chin or chest

  • Air or saliva is expelled from mouth with force

  • Seems frightened when there are sudden changes in own body position

  • Spells of laughter for no apparent reason during the day

  • Grinds teeth

  • Uses eye gaze to convey feelings, needs, and wishes

  • Shifts gaze with a slow horizontal turn of head

  • Spells of inconsolable crying for no apparent reason during the day

  • Spells of laughter for no apparent reason during the night

  • Spells of apparent panic

  • Has frequent naps during the day

  • Spells of screaming for no apparent reason during the day

  • Makes repetitive hand movements with hands apart

  • Screams hysterically for long periods of time and cannot be consoled

  • Spells of screaming for no apparent reason during the night

  • Vocalizes for no apparent reason

  • Rocks self when hands are prevented from moving

  • There are times when she appears miserable for no apparent reason

  • Abrupt changes in mood

  • Spells of inconsolable crying for no apparent reason during the night

  • Makes repetitive movements involving fingers around tongue

  • Rocks body repeatedly

  • Appears isolated

  • Vacant “staring” spells

  • Abdomen fills with air and sometimes feels hard

  • There are certain periods where she performs much worse than usual

  • There are times when she is irritable for no apparent reason

  • Seems to look through people into the distance

  • Although can stand independently tends to lean on objects or people

  • Expressionless face

  • Spells of apparent anxiety/fear in unfamiliar situations

  • Makes repetitive tongue movements

  • Walks with stiff legs

Select inclusion criteria6

  • Female subjects 5 to 20 years of age

  • Body weight ≥12 kg at screening

  • Could swallow the study medication provided as a liquid solution or could take it by gastrostomy tube

  • Had classic/typical RTT

  • Had a documented disease-causing mutation in the MECP2 gene

  • Had a stable pattern of seizures, or had no seizures within 8 weeks of screening