In short
BI-1607 is a promising new drug being investigated for patients with HER2-positive cancers, including breast cancer and gastric cancer. This monoclonal antibody targets CD32b (Fc Gamma Receptor IIB) and is designed to enhance the effectiveness of trastuzumab (Herceptin), a standard treatment for HER2-positive cancers. While trastuzumab has significantly improved survival rates, many patients develop resistance over time, leading to disease progression. Clinical trials are currently underway to evaluate how BI-1607, when combined with trastuzumab, might overcome this resistance and improve outcomes for patients whose cancers have progressed after standard therapy.
Key points
- BI-1607 is an innovative monoclonal antibody being tested in clinical trials for patients with HER2-positive cancers, including advanced breast and gastric cancers. The drug targets CD32b (Fc Gamma Receptor IIB) and is designed to enhance the effectiveness of trastuzumab (Herceptin), potentially overcoming resistance that many patients develop to standard treatments. The current Phase 1/2a trial administers BI-1607 intravenously every three weeks in combination with trastuzumab, first establishing the appropriate dose and then testing it in expanded patient groups. This approach represents a promising strategy for patients whose HER2-positive tumors have continued to progress despite receiving standard therapies, offering hope for improved treatment outcomes in these aggressive cancers.
At a glance
- Drug Name
- BI-1607
- Drug Type
- Human immunoglobulin G1 (IgG1) monoclonal antibody targeting CD32b (Fc Gamma Receptor IIB)
- Combination Therapy
- BI-1607 + Trastuzumab (Herceptin)
- Target Conditions
- HER2-positive advanced solid tumors including breast cancer, gastric cancer, and gastroesophageal junction adenocarcinoma
- Trial Phase
- Phase 1/2a, first-in-human
- Administration
- Intravenous infusions every 3 weeks
- Phase 1 Goal
- Assess safety, tolerability, and determine recommended Phase 2 dose (RP2D)
- Phase 2a Goal
- Collect additional safety data and detect early signs of clinical activity in specific cancer types
- Target Patient Population
- Patients whose tumors have progressed after standard therapy
- Primary Measurements
- Safety profile, dose-limiting toxicities, maximum tolerated dose
- Secondary Measurements
- Pharmacokinetics, immunogenicity, receptor occupancy, and antitumor activity
What is BI-1607?
BI-1607 is a new experimental drug being studied for treating certain types of cancer. Specifically, it is a human immunoglobulin G1 (IgG1) monoclonal antibody that targets a protein called CD32b, also known as Fc Gamma Receptor IIB. This medication is currently being investigated in clinical trials and is not yet approved for general use.
The drug is specifically designed to be used in combination with another medication called trastuzumab (brand name: Herceptin). Trastuzumab is an established treatment for certain cancers, but many patients develop resistance to it over time. BI-1607 aims to enhance trastuzumab's effectiveness and overcome this resistance problem.
How BI-1607 Works
BI-1607 has been engineered to target and block CD32b (Fc Gamma Receptor IIB), which is a protein found on certain immune cells. This receptor is thought to play a role in how cancer cells become resistant to treatments like trastuzumab.
By blocking CD32b, BI-1607 aims to:
- Enhance the effectiveness of trastuzumab treatment
- Help overcome resistance to trastuzumab in patients whose cancer has stopped responding to this treatment
- Potentially improve survival rates for patients with HER2-positive cancers
The drug is specifically designed as an Fc-engineered antibody, which means its structure has been modified to improve its function and interaction with the immune system.
Target Conditions
BI-1607 is being studied for the treatment of HER2-positive advanced solid tumors. HER2 (Human Epidermal Growth Factor Receptor 2) is a protein that promotes cancer cell growth. When a cancer has higher than normal levels of HER2, it is called "HER2-positive."
Specifically, the clinical trials are focusing on these conditions:
- HER2-positive breast cancer - Including locally advanced and metastatic (spread to other parts of the body) forms
- HER2-positive gastric (stomach) cancer - Including metastatic cases
- Metastatic gastroesophageal junction adenocarcinoma - Cancer at the junction between the esophagus and stomach that has spread to other parts of the body
These types of cancer are chosen because they often respond initially to trastuzumab treatment but may develop resistance over time, creating a need for new approaches like BI-1607.
Clinical Trial Information
BI-1607 is currently being studied in a Phase 1/2a clinical trial. This is an early-stage investigation to determine if the drug is safe and effective. The trial is described as "first-in-human," meaning this is the first time the drug is being tested in people.
The clinical trial has two main parts:
- Phase 1: This initial phase focuses on finding the right dose of BI-1607 to use with trastuzumab. Researchers gradually increase the dose in different groups of patients to determine which dose is both safe and potentially effective. The main goal is to assess safety, tolerability, and determine the recommended Phase 2 dose (RP2D).
- Phase 2a: Once the appropriate dose is determined, the study expands to include two groups of 15 patients each: The goals of this phase are to gather more safety data and look for early signs that the treatment is working.
- One group with locally advanced or metastatic HER2-positive breast cancer
- One group with HER2-positive metastatic gastric or gastroesophageal junction adenocarcinoma
This trial is specifically for patients whose cancer has progressed despite receiving standard treatments, representing an important potential option for those who have limited treatment alternatives.
Treatment Administration
In the clinical trial, BI-1607 is administered through intravenous (IV) infusions - meaning it's delivered directly into the bloodstream through a vein. These infusions are given every 3 weeks.
The combination treatment includes:
- BI-1607: Given at different doses during Phase 1 to determine the optimal amount. In Phase 2a, it is given at the recommended dose established during Phase 1.
- Trastuzumab (Herceptin): Administered at a loading dose of 8 mg/kg for the first infusion, followed by 6 mg/kg in subsequent infusions. Like BI-1607, trastuzumab is given every 3 weeks as an intravenous infusion.
Patients in the trial receive regular monitoring to assess how their body responds to the treatment, including blood tests and imaging studies to track the cancer's response.
Safety and Effectiveness
As BI-1607 is still in early clinical trials, comprehensive information about its safety profile and effectiveness is not yet available. However, the clinical trial is designed to carefully monitor several important aspects:
- Safety monitoring: Researchers track all side effects (adverse events) and serious side effects, rating their severity according to established criteria (National Cancer Institute Common Terminology Criteria for Adverse Events).
- Dose-limiting toxicities: The study identifies any side effects that are severe enough to limit the dose that can be given safely.
- Pharmacokinetics: The study examines how the drug moves through the body, including how quickly it's absorbed, distributed, and eliminated.
- Immunogenicity: Researchers check whether the patient's immune system develops antibodies against BI-1607, which could potentially reduce its effectiveness.
- Receptor occupancy: The study measures how effectively BI-1607 binds to its target (CD32b) on B cells in the blood.
To evaluate whether the treatment is working, researchers will assess:
- Objective response rate (ORR): The percentage of patients whose tumors shrink a meaningful amount
- Progression-free survival (PFS): How long patients live without their cancer getting worse
- Duration of response (DOR): How long any positive response to treatment lasts
- Overall survival (OS): How long patients live after starting treatment
Future Research
Beyond the basic safety and effectiveness evaluations, the clinical trial includes several exploratory research goals that may help improve future treatments:
- Investigating the levels of Fc receptors (including CD32b) and other immune markers in tumor samples to better understand how the drug works
- Studying patients' genetic profiles related to FcgammaR isoforms (variations in the receptors that BI-1607 targets) to see if certain genetic patterns might predict who will respond better to the treatment
- Exploring relationships between BI-1607 concentration in the blood and treatment outcomes or side effects
This additional research may help identify which patients are most likely to benefit from BI-1607, potentially leading to more personalized treatment approaches in the future.