LQTS Types 1, 2, and 3 are the most common types of LQTS, although other subtypes exist. LQTS Type 1 and LQTS Type 2 are caused by loss-of-function variants in two potassium channel genes (KCNQ1 and KCNH2, respectively). In contrast, LQTS Type 3 is caused by gain-of-function variants in a sodium channel gene (SCN5A). These gene variants change how currents travel through the heart, which lengthens the QT interval. Learn more about the different subtypes of LQTS here.

LQTS affects people with unpredictable symptoms and a constant sense of uncertainty. Those living with LQTS can experience persistent worry about fainting from an arrhythmia or suffering a life-threatening cardiac event, the effectiveness of their treatments, health of other affected family members and passing the condition to future generations. Emotional challenges such as anxiety, depression, and PTSD can be exacerbated by past cardiac events or receiving shocks from devices. The condition may also impact daily life, from limitations on physical activity to tolerance of medical treatments, creating significant psychological and physical burdens. The LQTS community urgently seeks better treatments and a cure. Learn more in the Sudden Arrhythmia Death Syndromes (SADS) Foundation Voice of the Patient Report here.

Long QT Syndrome (LQTS) affects males and females equally and has been identified across all ethnic groups. The estimated occurrence is approximately 1 in 2,000 live births, based on a clinical and genetic study of 44,500 newborns. (Source: National Organization for Rare Diseases)

Often undiagnosed, LQTS is believed to result in 3,000 to 4,000 sudden deaths in children and young adults each year in the United States. (Source: Boston Children’s Hospital)

Signs and Symptoms

• Fainting or seizure during exercise, excitement or startle.

• Family history of unexplained syncope, unexplained seizures, or sudden death in a young person.

Family History

• LQTS is a genetic disorder that is most often inherited but may also occur spontaneously via ‘de novo’ mutation.

• Family history of unexplained syncope, unexplained seizures, or sudden death in a young person are important for risk assessment.

Congenital Long QT Syndrome & SGK1

We are exploring the use of our novel SGK1 inhibitors as precision therapies to treat congenital Long QT Syndrome (LQTS). In cardiomyocytes derived from LQTS Types 1, 2, and 3 patients, our lead compound (LQT-1213) demonstrated a shortened action potential, which acts a surrogate for the QT interval. Similarly, we observed reductions in QT interval in tissue and animal models of drug-induced Long QT. In addition, all necessary non-clinical safety pharmacology studies were performed in order to move forward with clinical trials.

Our Phase 1 clinical study demonstrated that LQT-1213 appeared well tolerated, with good bioavailability and predictable pharmacokinetics in healthy volunteers. In our WAVE I Part 1 clinical proof-of-efficacy study, LQT-1213 rapidly and meaningfully reduced the QT interval in individuals with prolonged QT induced by dofetilide. Our WAVE I Part 2 clinical proof-of-efficacy study, demonstrated statistically significant and clinically meaningful reductions in QTcF in patients diagnosed with LQTS Types 2 and 3. Building on this success, we are preparing to initiate pivotal studies in 2025 to further evaluate LQT-1213 as a potential transformative treatment for LQTS. With these achievements, we continue to strive to have a meaningful impact on the lives of people with LQTS.

Real Life Long QT Syndrome Journeys

Visit our Shared Stories to learn how Long QT Syndrome impacts the lives of everyday people.

If you are concerned about your personal health, please speak to a specialist or your healthcare provider urgently.