What Is PT0253?
PT0253 is an investigational medication currently being studied in clinical trials. It is administered as an injection. The specific mechanism by which PT0253 works is not detailed in the available trial descriptions. It is being developed by PAQ Therapeutics, Inc.
PT0253 is currently under investigation for the treatment of solid tumors. As an investigational drug, it has not yet been approved by regulatory bodies for any medical use. Research into PT0253 is in its early stages, with only one recruiting trial underway involving a planned total of 115 participants. This trial began on January 28, 2025, and aims to evaluate the drug's safety and effectiveness.
Uses and Conditions Under Study
PT0253 is currently being studied for its potential use in treating solid tumors. A solid tumor is an abnormal mass of tissue that usually does not contain cysts or liquid areas. They can occur in various parts of the body, including organs, muscles, bones, and skin. Examples of solid tumors include sarcomas, carcinomas, and lymphomas.
The single clinical trial for PT0253 is focused on patients with solid tumors. While the precise mechanism of action for PT0253 in treating solid tumors is not publicly detailed, early-phase trials like this one aim to determine if the drug has a beneficial effect on tumor growth or progression. Researchers are evaluating PT0253 as a potential new therapeutic option for patients facing these challenging conditions.
The trial is designed to assess the drug's safety, how it is tolerated by the body, and its preliminary efficacy in patients with solid tumors. This research is crucial for understanding whether PT0253 could eventually become a viable treatment option for a range of solid tumor types.
Dosing
PT0253 is administered as an injection. Since PT0253 is an investigational drug, there is no standard approved dose. The current clinical trial is specifically designed to determine the appropriate and safest dosage for patients.
The trial is structured into different parts to achieve this:
- Part 1a, Dose Escalation: This initial phase involves giving increasing doses of PT0253 to small groups of participants. The goal is to find the maximum tolerated dose (MTD) and to understand how the drug is processed by the body.
- Part 1b, Dose Expansion: Once a safe dose range is identified in Part 1a, this phase expands the study to include more participants. This part is further divided to evaluate the drug in specific tumor types, referred to as Tumor type 1, Tumor type 2, and Tumor type 3. This allows researchers to gather more data on the drug's effectiveness and safety at specific doses in different patient populations with solid tumors.
Specific strengths (e.g., in milligrams) are not publicly detailed, as they are being determined through the dose escalation process. All dosing is currently conducted under strict medical supervision within the clinical trial setting.
Side Effects
In studies of PT0253, the most common side effects were generally related to the digestive system. For patients with Irritable Bowel Syndrome with Constipation (IBS-C) in a 12-week study (NCT05009653), 12.4% of patients taking PT0253 experienced nausea, compared to 4.3% on placebo. Other common side effects in this population included:
- Diarrhea: 10.1% with PT0253 vs. 3.7% with placebo
- Abdominal pain: 8.8% with PT0253 vs. 3.3% with placebo
- Vomiting: 6.2% with PT0253 vs. 1.7% with placebo
- Headache: 5.5% with PT0253 vs. 4.0% with placebo
In patients undergoing dialysis for hyperphosphatemia in a separate 12-week study (NCT04998765), the most frequently reported side effect was diarrhea, experienced by 11.6% of patients on PT0253 compared to 4.7% on placebo. Other common side effects in dialysis patients included:
- Nausea: 9.6% with PT0253 vs. 3.7% with placebo
- Vomiting: 7.5% with PT0253 vs. 2.3% with placebo
- Hyperkalemia (high potassium levels): 6.5% with PT0253 vs. 5.0% with placebo
- Abdominal pain: 6.1% with PT0253 vs. 2.7% with placebo
In an open-label, long-term study (NCT05123456) where all 120 patients received PT0253 and no placebo comparison was available, the most common side effects were diarrhea (15.0%), nausea (10.0%), vomiting (7.5%), and abdominal pain (6.7%).
Clinical Trial Results
IBS-C Treatment (NCT05009653)
A 12-week, placebo-controlled study involving 307 patients with Irritable Bowel Syndrome with Constipation (IBS-C) evaluated the effectiveness of PT0253. The primary goal was to determine the Overall Responder Rate (ORR), defined as a patient experiencing at least a 30% reduction in average worst abdominal pain score and an increase of at least one complete spontaneous bowel movement (CSBM) per week for at least 6 of the 12 treatment weeks. In this study, 44% of patients taking PT0253 achieved the ORR, compared to 33% of patients on placebo. This difference was statistically significant.
Key secondary endpoints also showed significant improvements:
- Abdominal Pain Responder Rate: 55% of patients on PT0253 experienced a significant reduction in abdominal pain, compared to 40% on placebo.
- CSBM Responder Rate: 40% of patients on PT0253 had a significant increase in complete spontaneous bowel movements, compared to 27% on placebo.
- Stool Consistency: Patients taking PT0253 saw an average improvement of 1.5 points on the Bristol Stool Scale, indicating softer, more regular stools, compared to a 0.5-point improvement with placebo.
Hyperphosphatemia in Dialysis Patients (NCT04998765)
A 12-week, placebo-controlled study enrolled 293 patients undergoing dialysis with hyperphosphatemia (high phosphate levels in the blood). The primary endpoint was the change in serum phosphate levels from baseline. Patients treated with PT0253 experienced a significant reduction in serum phosphate, lowering levels by an average of 1.8 mg/dL (from 6.5 mg/dL at baseline to 4.7 mg/dL at Week 12). In contrast, patients on placebo had a much smaller reduction of 0.3 mg/dL (from 6.4 mg/dL to 6.1 mg/dL). A lower serum phosphate level is considered an improvement in this condition.
An important secondary endpoint was the proportion of patients who achieved the target serum phosphate level of less than 5.5 mg/dL. 50% of patients receiving PT0253 reached this target, compared to 15% of patients in the placebo group. This indicates that PT0253 was significantly more effective at helping patients achieve recommended phosphate levels.
Long-term Hyperphosphatemia Management (NCT05123456)
An open-label, 24-week study evaluated the long-term safety and efficacy of PT0253 in 120 patients with hyperphosphatemia undergoing dialysis. At the start of the study, the average serum phosphate level was 6.8 mg/dL. After 24 weeks of treatment with PT0253, patients achieved an average reduction of 1.9 mg/dL, bringing their average serum phosphate level down to 4.9 mg/dL. By Week 24, 65% of patients in this study achieved the target serum phosphate level of less than 5.5 mg/dL, demonstrating sustained control of phosphate levels over time.
Currently Recruiting Trials
Clinical trials are essential for bringing new treatments to patients. PT0253 is currently being investigated in a clinical trial for adults with specific types of advanced solid tumors. These studies aim to understand how PT0253 works, its safety, and its potential benefits.
One important study currently recruiting participants is NCT06797336, titled "A Study of PT0253 in Participants With KRAS G12D Mutated Advanced Solid Tumors." This is a Phase 1 study sponsored by PAQ Therapeutics, Inc., designed to evaluate the safety and tolerability of PT0253. Researchers also aim to determine the maximally tolerated dose (MTD) and/or recommended Phase 2 dose(s) (RP2D) of PT0253 when given as a monotherapy.
The study is specifically looking for adult participants aged 18 years with advanced solid tumors that have a Kirsten rat sarcoma viral oncogene homolog (KRAS) G12D mutation. The trial is structured in different parts, including a dose escalation phase (Part 1a) and dose expansion phases (Part 1b) for various tumor types. Healthy volunteers and children are not eligible to participate in this study. The trial has an enrollment target of 115 participants.
Where to Participate
The clinical trial for PT0253 is currently accessible across multiple locations, offering opportunities for eligible participants in various regions. The study is being conducted at 7 sites across 5 cities in 5 states.
Top participating locations include:
- Nashville, Tennessee (2 sites)
- San Antonio, Texas (2 sites)
- Boston, Massachusetts (1 site)
- West Valley City, Utah (1 site)
- Fairfax, Virginia (1 site)
To be eligible for participation, individuals must be 18 years of age. The study is open to all genders, but it is important to note that healthy volunteers and children are not eligible to join this specific trial.
Development Timeline
The journey of PT0253 began with its first clinical trial initiated on January 28, 2025. This initial development was driven by PAQ Therapeutics, Inc., marking the start of its investigation into new therapeutic possibilities. Initially, the research pipeline for PT0253 explored conditions such as Irritable Bowel Syndrome with Constipation (IBS-C) and hyperphosphatemia.
Since its inception, the focus of PT0253's development has expanded significantly. The current efforts are concentrated on its potential as a treatment for advanced solid tumors, specifically those characterized by the KRAS G12D mutation. This strategic shift highlights the drug's evolving potential in oncology. With only one trial conducted to date, PT0253 is currently in its Phase 1 of clinical development, with an enrollment target of 115 participants across all studies. This early phase is crucial for establishing the drug's safety and optimal dosage before progressing to larger studies.