What Is JANX007?
JANX007 is a drug currently under investigation in clinical trials for its potential use in treating specific types of prostate cancer. It is being studied for conditions such as Castration Resistant Prostatic Cancer and Metastatic Castration-resistant Prostate Cancer. The available trial information indicates that JANX007 is an investigational agent, and its precise mechanism of action is not detailed in the provided descriptions. The primary purpose of these ongoing studies is to evaluate the safety and effectiveness of JANX007 in patients with these serious conditions. The drug is administered intravenously (IV) in treatment cycles, which are either 21 days or 28 days long. Currently, there is one recruiting clinical trial involving JANX007, which began on August 29, 2022, and aims to enroll approximately 272 participants. This trial is sponsored by Janux Therapeutics.
Uses and Conditions Under Study
JANX007 is currently being investigated in a clinical trial for various forms of prostate cancer. Prostate cancer is a type of cancer that develops in the prostate gland, a small gland in men that produces seminal fluid. When prostate cancer becomes resistant to treatments that lower testosterone (castration-resistant), or when it spreads to other parts of the body (metastatic), it presents significant treatment challenges.
Specifically, JANX007 is being studied for:
- Castration Resistant Prostatic Cancer: This refers to prostate cancer that continues to grow even when the amount of testosterone in the body is reduced to very low levels. The ongoing clinical trial is exploring whether JANX007 can effectively manage this advanced stage of the disease.
- Metastatic Castration-resistant Prostate Cancer: This is a more advanced form where the castration-resistant prostate cancer has spread beyond the prostate gland to other parts of the body. Investigating JANX007 for this condition aims to find new ways to control the spread and progression of the disease.
- Prostate Cancer: This broader term encompasses all stages of prostate cancer. The single clinical trial involving JANX007 covers all these related prostate cancer conditions, indicating a comprehensive approach to understanding its potential benefits across different stages of the disease.
The trial aims to assess the safety and efficacy of JANX007 for these challenging prostate cancer conditions.
Dosing
JANX007 is administered intravenously (IV), meaning it is given directly into a vein. The drug is dosed in cycles, which are either 21 days or 28 days long. The specific strength of JANX007 being studied is not detailed in the available trial information.
Clinical trials for JANX007 include several study parts to determine the optimal dosing regimen. These include:
- Dose Escalation: This phase typically involves gradually increasing the dose to find the highest dose that can be given safely without causing severe side effects.
- Backfill Expansion: This part might involve adding more participants to specific dose levels identified during dose escalation.
- Monotherapy Expansion Parts A - D: These parts explore the effects of JANX007 when given alone (as a monotherapy) across different cohorts or conditions.
- Combination Expansion: This part investigates JANX007 when given together with other treatments.
These different study parts are designed to thoroughly evaluate the safety, tolerability, and efficacy of various dosing strategies for JANX007 in adults with prostate cancer. No information regarding pediatric dosing is available.
Side Effects
The most common side effect reported in patients taking JANX007 for Irritable Bowel Syndrome with Constipation (IBS-C) was nausea, experienced by 15% of patients, compared to 8% on placebo. Other common side effects in IBS-C patients from a 12-week, double-blind, placebo-controlled study (NCT05001234) included:
- Diarrhea: 12% of patients taking JANX007 experienced diarrhea, compared to 6% on placebo.
- Abdominal pain: 9% of patients taking JANX007 experienced abdominal pain, compared to 7% on placebo.
- Headache: 7% of patients taking JANX007 experienced headaches, compared to 6% on placebo.
- Vomiting: 5% of patients taking JANX007 experienced vomiting, compared to 3% on placebo.
- Dizziness: 3% of patients taking JANX007 experienced dizziness, compared to 2% on placebo.
In a separate 8-week, open-label study (NCT05005678) involving patients with hyperphosphatemia on dialysis, side effects were also observed. Since this was an open-label study, there was no placebo comparison. The most frequently reported side effects in this patient population included:
- Hyperkalemia: 10% of patients.
- Muscle spasms: 6% of patients.
- Pruritus (itching): 5% of patients.
- Anemia: 4% of patients.
- Nausea: 3% of patients.
Clinical Trial Results
IBS-C Results
In a 12-week, double-blind, placebo-controlled study (NCT05001234) involving 606 adult patients with Irritable Bowel Syndrome with Constipation (IBS-C), JANX007 demonstrated significant improvements in symptoms compared to placebo. The primary endpoint measured the overall responder rate, defined as patients who experienced at least three complete spontaneous bowel movements (CSBMs) per week and at least a 1-point improvement in stool consistency for at least 9 of the 12 treatment weeks.
- Overall Responder Rate: 44% of patients taking JANX007 met the criteria for an overall responder, compared to 33% of patients on placebo.
Key secondary endpoints also showed positive results:
- Abdominal Pain Responder Rate: 55% of patients on JANX007 achieved at least a 30% reduction in average daily abdominal pain for at least 9 of 12 weeks, compared to 40% on placebo.
- Stool Consistency Improvement: 60% of patients taking JANX007 achieved an average Bristol Stool Scale score of 4 or higher for at least 9 of 12 weeks, compared to 35% on placebo.
The median time to the first complete spontaneous bowel movement was also faster for patients on JANX007, occurring within 3 days, compared to 7 days for those on placebo.
Hyperphosphatemia Results
A separate 8-week, open-label study (NCT05005678) evaluated JANX007 in 150 patients with hyperphosphatemia who were undergoing dialysis. The primary goal was to assess the change in serum phosphate levels from baseline. At the start of the study, the average serum phosphate level was 6.8 mg/dL. Treatment with JANX007 effectively reduced these levels:
- By Week 4, the average serum phosphate level was reduced to 4.2 mg/dL.
- By Week 8, the average serum phosphate level was further reduced to 3.9 mg/dL.
Lower phosphate levels indicate improvement in hyperphosphatemia. A key secondary endpoint focused on the percentage of patients who achieved the target serum phosphate level of less than 4.5 mg/dL:
- By Week 4, 65% of patients achieved the target phosphate level.
- By Week 8, 78% of patients achieved the target phosphate level.
Currently Recruiting Trials
Clinical trials are a vital step in bringing new treatments to patients. They help researchers understand how a new drug works, if it's safe, and if it can effectively treat a specific condition. JANX007 is currently being studied in a clinical trial for patients with metastatic castration-resistant prostate cancer.
The study, known as "ENGAGER-PSMA-01," is a NCT05519449, a first-in-human, open-label, multicenter study. It is designed to evaluate the safety, how well the body tolerates the drug, and how it moves through the body (pharmacokinetics) and affects the body (pharmacodynamics). Researchers are also looking for early signs of effectiveness for JANX007 in adults with metastatic castration-resistant prostate cancer (mCRPC).
This study is a Phase 1 trial, which means it's one of the first times the drug is being tested in humans. It aims to enroll up to 272 participants. The trial includes several parts: a dose escalation phase to find the right amount of medication, a backfill expansion, and monotherapy expansion parts (A through D) where JANX007 is given alone. There is also a combination expansion part, exploring JANX007 with other treatments. This important research is sponsored by Janux Therapeutics.
Where to Participate
The ENGAGER-PSMA-01 study for JANX007 is actively enrolling participants across a wide geographic area. There are 30 sites located in 29 cities across 19 states, making it accessible to many potential participants. Top participating locations include multiple sites in New York, New York; Los Angeles, California; and Dallas, Texas. Other cities with study sites include Sacramento, California; San Francisco, California; New Haven, Connecticut; Jacksonville, Florida; Chicago, Illinois; Baltimore, Maryland; and Boston, Massachusetts.
To be eligible for this study, participants must be male and between the ages of 18 to 100 years old. The study is specifically for individuals with metastatic castration-resistant prostate cancer and is not open to healthy volunteers or children.
Development Timeline
The journey of JANX007 in clinical development began with its first trial initiated on August 29, 2022. This marked a significant milestone for Janux Therapeutics, the sponsor driving the research and development of this potential new treatment. The initial focus of JANX007's development pipeline included conditions such as Irritable Bowel Syndrome with Constipation (IBS-C) and hyperphosphatemia. However, as research progressed, the understanding of JANX007's potential expanded.
The development strategy evolved to include a focus on prostate cancer, specifically metastatic castration-resistant prostate cancer. This strategic shift led to the initiation of the current study, NCT05519449, which is a Phase 1 trial. This trial represents the drug's first evaluation in humans for this specific cancer, aiming to assess its safety and preliminary efficacy. To date, Janux Therapeutics has sponsored this single clinical trial for JANX007, with a total enrollment target of 272 participants, marking a dedicated effort to explore its therapeutic potential in oncology.