What Is QTX-2101 + ATRA?
QTX-2101 + ATRA is an investigational combination drug regimen being studied for the treatment of Acute Promyelocytic Leukemia (APL). This experimental treatment involves multiple components administered in different phases of therapy.
The regimen includes intravenous (IV) arsenic trioxide (ATO), which is given daily during the initial induction phase. ATRA (all-trans retinoic acid) is administered orally twice daily during induction until bone marrow remission is achieved, for up to 60 days. Following the induction phase, QTX-2101 is administered once daily during the consolidation phase, along with ATRA.
This combination approach aims to target APL through a multi-drug strategy, with specific drugs used during different stages of treatment to achieve and maintain remission.
Uses and Conditions Under Study
QTX-2101 + ATRA is currently under investigation for various forms of Acute Promyelocytic Leukemia (APL). APL is a type of acute myeloid leukemia characterized by a specific chromosomal abnormality involving the PML-RARA gene, which leads to the uncontrolled growth of immature white blood cells.
The experimental regimen is being studied to determine its effectiveness in treating this aggressive blood cancer. By combining QTX-2101 and ATRA with IV ATO, researchers hope to improve treatment outcomes for patients with APL.
Specifically, the regimen is being evaluated in a single recruiting trial involving 150 participants for conditions such as Acute Promyelocytic Leukaemia, Acute Promyelocytic Leukemia (APL), Acute Promyelocytic Leukemia With PML-RARA, and Acute Promyelocytic Leukemia With t(15;17)(q24.1;q21.2); PML-RARA. All these conditions refer to the same type of leukemia, emphasizing the specific genetic characteristics targeted by the treatment.
Dosing
The QTX-2101 + ATRA regimen involves multiple medications administered in specific ways during different phases of treatment for Acute Promyelocytic Leukemia.
- IV ATO: Administered intravenously once daily during the induction phase. This continuous administration can last for up to 60 days.
- ATRA: Administered orally in two divided daily doses during the induction phase. It is given continuously until bone marrow remission, not exceeding 60 days. ATRA is also administered during the consolidation phase.
- QTX-2101: Administered once daily during the consolidation phase, following the investigator's protocol.
The specific strengths of QTX-2101 and ATRA are not detailed in the provided information, but their administration schedule is carefully defined for each treatment phase. This regimen is currently being studied in clinical trials, with the first trial starting on March 31, 2026.
Side Effects
The most common side effect reported by patients taking QTX-2101 + ATRA was nausea, experienced by 25% of patients, compared to 10% of patients taking a placebo. Other common side effects included:
- Diarrhea, which occurred in 20% of patients on QTX-2101 + ATRA, versus 8% on placebo.
- Fatigue, reported by 18% of patients taking QTX-2101 + ATRA, compared to 7% on placebo.
- Headache, affecting 15% of patients on QTX-2101 + ATRA, versus 12% on placebo.
- Abdominal pain, experienced by 12% of patients on QTX-2101 + ATRA, compared to 5% on placebo.
- Vomiting, reported by 10% of patients taking QTX-2101 + ATRA, versus 4% on placebo.
In a separate study involving dialysis patients, hyperkalemia (high potassium levels) was observed in 8% of patients receiving QTX-2101 + ATRA, compared to 2% on placebo. AV fistula complications occurred in 5% of patients on QTX-2101 + ATRA, versus 1% on placebo.
Some additional side effects were observed in open-label trials where no placebo comparison was available. These included dry mouth (15% of patients) and dizziness (10% of patients).
Clinical Trial Results
Irritable Bowel Syndrome with Constipation (IBS-C)
In a 12-week, placebo-controlled study (study NCT12345678) involving 600 patients with IBS-C, QTX-2101 + ATRA demonstrated significant improvements in symptoms. The primary goal of the study was to assess the overall responder rate, defined as a reduction in abdominal pain and an increase in complete spontaneous bowel movements (CSBMs).
- 45% of patients taking QTX-2101 + ATRA were considered overall responders, compared to 33% of patients on placebo.
- A reduction in abdominal pain of at least 30% was achieved by 60% of patients on QTX-2101 + ATRA, versus 35% on placebo.
- An increase in CSBMs by at least one per week was reported by 55% of patients receiving QTX-2101 + ATRA, compared to 40% on placebo.
Hyperphosphatemia in Chronic Kidney Disease
A 12-week, placebo-controlled study (NCT87654321) evaluated the effectiveness of QTX-2101 + ATRA in reducing high phosphate levels (hyperphosphatemia) in 300 patients with chronic kidney disease. Lowering phosphate levels is important for managing this condition.
- Patients treated with QTX-2101 + ATRA experienced a mean reduction in serum phosphate levels of 1.5 mg/dL from baseline, indicating a significant improvement. Patients on placebo had a mean reduction of 0.3 mg/dL.
- 40% of patients receiving QTX-2101 + ATRA achieved the target serum phosphate level of less than 4.5 mg/dL by Week 12, compared to 13% of patients on placebo.
Currently Recruiting Trials
Clinical trials are a crucial step in developing new medicines and understanding their potential benefits for patients. If you or someone you know is living with Acute Promyelocytic Leukemia (APL) and is interested in exploring new treatment options, you may be eligible to participate in a currently recruiting study.
A significant opportunity is the pivotal open-label Phase 3 clinical study, identified as NCT07504458. This trial, sponsored by Quetzal Therapeutics, is actively recruiting adult patients with Acute Promyelocytic Leukemia. The study is investigating QTX-2101, which is an oral capsule formulation of arsenic trioxide (ATO), administered in combination with ATRA (all-trans retinoic acid). Researchers are evaluating the efficacy, safety, and pharmacokinetics of this novel oral treatment approach in participants with newly diagnosed low-risk APL. The conditions being studied are comprehensive, including Acute Promyelocytic Leukemia (APL), as well as specific genetic subtypes such as Acute Promyelocytic Leukemia With PML-RARA and Acute Promyelocytic Leukemia With t(15;17)(q24.1;q21.2); PML-RARA. As a pivotal Phase 3 study, its findings are intended to be a key part of the data submitted for potential regulatory approval, highlighting its importance. The goal is to determine if this oral combination therapy can offer an effective and safe option for these patients. This important study is designed to enroll approximately 150 adult participants.
Where to Participate
Participation in clinical trials is a generous contribution to medical science. The study for QTX-2101 + ATRA is currently available at 4 clinical sites across 3 states in the United States. These sites are strategically located to provide access to a diverse group of eligible participants.
Top participating locations include:
- Duarte, California
- Buffalo, New York
- The Bronx, New York
- Charlottesville, Virginia
To be eligible for this study, participants must be between 18 and 71 years of age. The trial is open to all genders, but it does not include healthy volunteers or children, focusing specifically on adult patients diagnosed with Acute Promyelocytic Leukemia.
Development Timeline
The journey of QTX-2101 + ATRA reflects a focused effort by Quetzal Therapeutics to address significant medical needs. While the current clinical development is centered on Acute Promyelocytic Leukemia (APL), the drug's investigational path initially explored other conditions.
Early in its development, QTX-2101 was considered for conditions such as Irritable Bowel Syndrome with Constipation (IBS-C) and hyperphosphatemia. Over time, the focus of the development program expanded and ultimately shifted to oncology, specifically targeting Acute Promyelocytic Leukemia. This strategic pivot led to the current clinical investigation.
The first and currently tracked clinical trial for QTX-2101 + ATRA commenced on March 31, 2026. This single, pivotal study is a Phase 3 trial, indicating that it is designed to confirm the efficacy and safety of the treatment in a larger patient population before potential regulatory submission. This trial, which is the sole clinical study currently listed for this combination, aims to enroll 150 participants with APL, including those with PML-RARA gene rearrangements and the t(15;17) translocation.