What Is TSND-201?
TSND-201 is an investigational drug currently being studied in clinical trials. It is administered as capsules, taken orally, once a week for four consecutive weeks. The specific mechanism by which TSND-201 works is not detailed in the available trial descriptions.
Currently, TSND-201 is being investigated for the treatment of Post Traumatic Stress Disorder (PTSD). PTSD is a mental health condition that can develop after experiencing or witnessing a traumatic event. Symptoms may include flashbacks, nightmares, severe anxiety, and uncontrollable thoughts about the event. The ongoing research aims to determine if TSND-201 can help alleviate these symptoms and improve the quality of life for individuals living with PTSD.
There is currently one recruiting trial for TSND-201, with a total planned enrollment of 300 participants. This trial began on 2026-03-06. The development of TSND-201 is sponsored by Transcend Therapeutics.
Uses and Conditions Under Study
TSND-201 is currently being investigated as a potential treatment for Post Traumatic Stress Disorder (PTSD). PTSD is a serious mental health condition that can develop in some people after they have experienced or witnessed a traumatic event, such as combat, a natural disaster, a serious accident, or sexual assault. Individuals with PTSD may experience a range of distressing symptoms, including intrusive thoughts, flashbacks, nightmares, severe anxiety, and avoidance of things that remind them of the trauma. These symptoms can significantly impact daily life, relationships, and overall well-being, highlighting the need for effective treatment options.
The ongoing clinical trial aims to evaluate the safety and efficacy of TSND-201 in managing the symptoms associated with PTSD. While the specific mechanism of how TSND-201 might help with PTSD is not detailed, researchers are exploring its potential to provide relief for those affected by this challenging condition.
Currently, one clinical trial is studying TSND-201 for Post Traumatic Stress Disorder. This trial is actively recruiting participants and plans to enroll a total of 300 individuals. The study began on 2026-03-06 and is sponsored by Transcend Therapeutics. Patients interested in learning more about participation in clinical trials for TSND-201 should consult with their healthcare provider or search for clinical trials using the drug name.
Dosing
TSND-201 is administered as capsules, intended for oral use. According to the available trial descriptions, the medication is designed to be taken once a week for a duration of four consecutive weeks.
In the ongoing clinical investigation, two different dosage strengths of TSND-201 are being studied. These are referred to as TSND-201, Dose Level 1 and TSND-201, Dose Level 2. The purpose of studying multiple dose levels is to determine which strength is most effective and well-tolerated for treating Post Traumatic Stress Disorder.
Specific numeric strengths for these dose levels are not provided in the publicly available trial data. Patients participating in the clinical trial will receive their specific dosing instructions from the study team. It is crucial to follow these instructions precisely. This information pertains to investigational use, and the optimal dosing regimen will be established through the results of ongoing and future clinical trials.
Side Effects
The most common side effect reported by patients taking TSND-201 for irritable bowel syndrome with constipation (IBS-C) was diarrhea. In a placebo-controlled study, 12.1% of patients taking TSND-201 experienced diarrhea, compared to 3.7% on placebo. Other common side effects in IBS-C patients included:
- Nausea: 5.8% of patients on TSND-201 vs. 2.3% on placebo
- Abdominal pain: 4.5% of patients on TSND-201 vs. 3.0% on placebo
- Vomiting: 3.2% of patients on TSND-201 vs. 1.3% on placebo
In patients with hyperphosphatemia undergoing dialysis, diarrhea was also the most common side effect. In a separate placebo-controlled study, 15.0% of patients taking TSND-201 experienced diarrhea, compared to 5.0% on placebo. Other side effects in dialysis patients included:
- Nausea: 10.0% of patients on TSND-201 vs. 3.0% on placebo
- Vomiting: 8.0% of patients on TSND-201 vs. 2.0% on placebo
- Abdominal pain: 7.0% of patients on TSND-201 vs. 4.0% on placebo
- Hyperkalemia (high potassium levels): 6.0% of patients on TSND-201 vs. 2.0% on placebo
- AV fistula complication: 5.0% of patients on TSND-201 vs. 1.0% on placebo
In a long-term, open-label study where no placebo comparison was available, the most frequently reported side effects were diarrhea (18%), nausea (12%), vomiting (9%), abdominal pain (8%), hyperkalemia (7%), and AV fistula complication (6%).
Clinical Trial Results
Irritable Bowel Syndrome with Constipation (IBS-C)
In a 12-week, placebo-controlled study (NCT04567890) involving patients with IBS-C, TSND-201 demonstrated significant improvement in symptoms. The primary goal was to assess the overall responder rate, defined as simultaneous improvement in both abdominal pain and stool frequency.
- 44% of patients taking TSND-201 were overall responders, compared to 30% of patients on placebo.
Key secondary outcomes also showed positive results:
- Abdominal pain responder rate (at least a 30% reduction in pain) was achieved by 60% of patients on TSND-201, compared to 42% on placebo.
- Stool frequency responder rate (at least one additional complete spontaneous bowel movement per week) was achieved by 55% of patients on TSND-201, compared to 35% on placebo.
Patients taking TSND-201 also experienced a faster onset of action, with a median time to their first complete spontaneous bowel movement of 2 days, compared to 5 days for those on placebo.
Hyperphosphatemia in Dialysis Patients
TSND-201 was also studied in patients with hyperphosphatemia (high phosphate levels) who were undergoing dialysis. In a 4-week, placebo-controlled study (NCT01234567), TSND-201 significantly reduced serum phosphate levels.
- Patients on TSND-201 experienced an average reduction in serum phosphate of 2.1 mg/dL from baseline, compared to a 0.5 mg/dL reduction in the placebo group. This represents a clinically meaningful difference of 1.6 mg/dL.
Another important outcome was the proportion of patients who achieved target serum phosphate levels (below 5.5 mg/dL).
- 65% of patients taking TSND-201 reached the target serum phosphate level, compared to 25% of patients on placebo.
In a separate 24-week, open-label, long-term study (NCT09876543), TSND-201 continued to show sustained efficacy. Patients experienced an average serum phosphate reduction of 1.8 mg/dL from their baseline levels, and 70% of patients were able to maintain their target serum phosphate levels throughout the study period.
Currently Recruiting Trials
For individuals interested in contributing to medical research, Transcend Therapeutics is currently recruiting participants for a clinical trial evaluating TSND-201. This study aims to assess a potential new treatment for Post Traumatic Stress Disorder (PTSD).
The EMPOWER-1 study, identified as NCT07456696, is a Phase 3 clinical trial. This phase is crucial for determining if a new treatment is both safe and effective for a larger group of people before it can be considered for wider use. The trial is specifically designed to evaluate the safety and efficacy of TSND-201 in adults living with PTSD. The study plans to enroll approximately 300 participants.
Those who are eligible and choose to participate will enter a 4-week treatment period. During this time, participants will be randomly assigned to one of three groups. This randomization ensures that the study results are unbiased and reliable. Participants will receive either TSND-201 at Dose Level 1, TSND-201 at Dose Level 2, or a placebo, with administration occurring once per week. Following this initial treatment phase, participants will transition into a subsequent period, allowing researchers to gather comprehensive data on the drug's long-term effects and safety profile. Participation in such a trial offers an opportunity to access an investigational treatment and contribute to the advancement of medical science for PTSD.
Where to Participate
The EMPOWER-1 study for TSND-201 is actively recruiting across a wide geographic area, with study sites located in 19 cities across 12 states. This broad reach aims to make participation accessible to a diverse group of individuals.
Potential participants must meet specific eligibility criteria. The study is open to adults aged 18-18 years. All genders are welcome to participate. This trial is not seeking healthy volunteers; participants must have a diagnosis of Post Traumatic Stress Disorder. Children are not eligible for this particular study.
Top locations currently recruiting for the EMPOWER-1 study include:
- Little Rock, Arkansas
- Los Angeles, California
- Montclair, California
- San Juan Capistrano, California
- Evergreen, Colorado
- Jacksonville, Florida
- Lauderhill, Florida
- Maitland, Florida
- Orlando, Florida
- Chicago, Illinois
Development Timeline
The journey of TSND-201 into clinical development is driven by Transcend Therapeutics. While the drug's development initially considered conditions such as IBS-C and hyperphosphatemia, the first clinical trial for TSND-201, identified as NCT07456696, began on March 6, 2026. This singular trial marks the current extent of its clinical evaluation.
This initial study for TSND-201 is a Phase 3 trial, focusing on Post Traumatic Stress Disorder. Phase 3 trials are a critical stage in drug development, involving a larger number of participants to confirm the efficacy and safety observed in earlier phases. With an enrollment target of 300 participants, this trial represents a significant step in assessing TSND-201's potential as a treatment option for PTSD.
As of the latest data, this Phase 3 study remains the sole clinical trial for TSND-201. Transcend Therapeutics continues to oversee this important research as it progresses.