Intensity Therapeutics Reports Improved Safety Profile for INT230-6 in Triple Negative Breast Cancer Trial
核心洞察
Intensity Therapeutics' INVINCIBLE-4 Phase 2 trial shows INT230-6 plus standard of care resulted in 50% fewer grade 3 or higher adverse events compared to standard chemotherapy alone in triple negative breast cancer (搜索) patients.
The company is modifying the dosing protocol to a single injection at lower volumes after observing skin and tissue necrosis in some patients who received two doses of INT230-6.
Intensity plans to pursue a potential Phase 3 trial design that could eliminate the cardiotoxic anthracycline doxorubicin from treatment regimens while maintaining efficacy.
Intensity Therapeutics announced promising early safety data from its INVINCIBLE-4 Phase 2 clinical trial, showing that patients with triple negative breast cancer (搜索) (TNBC (搜索)) who received the experimental drug INT230-6 plus standard of care experienced significantly fewer severe adverse events compared to those receiving standard chemotherapy alone. The findings were presented at the 2025 San Antonio Breast Cancer (搜索) Symposium.
Improved Safety Profile in Early Trial Results
The INVINCIBLE-4 study, which began enrollment in 2024, has treated 14 patients with seven in each treatment arm. Patients receiving INT230-6 plus standard of care experienced nine grade 3 or higher adverse events, while those receiving standard of care alone experienced 20 such events through November 10th - representing a 50% reduction in severe toxicities.
"The safety data for the patients who received INT230-6 plus SOC continues to be favorable compared to the standard of care alone," according to the company's presentation data. The trial is evaluating intratumoral injections of INT230-6 prior to neoadjuvant immunochemotherapy in early-stage TNBC (搜索) patients.
Protocol Modifications Following Tissue Necrosis Observations
The company is implementing protocol changes after observing concerning tissue effects in some patients. While a patient with a 2.2 cm tumor who received one dose showed only skin irritation at surgery, patients receiving two doses experienced skin and adipose tissue necrosis visible on MRI scans, requiring additional surgical intervention.
As a result, Intensity is modifying the protocol to administer a single dose at lower volumes based on tumor size. If tumor necrosis is observed on MRI after the first INT230-6 dose, a second injection will not be administered. The company plans to restart patient enrollment using this modified dosing regimen.
Potential Anthracycline-Free Treatment Pathway
Based on the early safety and efficacy trends, Intensity is exploring a Phase 3 trial design that could eliminate doxorubicin, a highly cardiotoxic anthracycline commonly called "the red devil" by patients and physicians. The current standard of care includes pembrolizumab immunotherapy, doxorubicin, carboplatin, cyclophosphamide, and taxane.
A potential three-arm Phase 3 trial could compare INT230-6 with standard of care, current standard of care alone, and INT230-6 with standard of care minus the anthracycline component. This approach could address the significant cardiotoxicity concerns associated with doxorubicin while maintaining treatment efficacy.
Christine Handy, a breast cancer (搜索) survivor and patient advocate who co-authored one of the symposium presentations, noted her experience with permanent cardiotoxicity from doxorubicin treatment. "Patients can be harmed by the treatment for this potentially deadly disease and often have to make a difficult choice as some fear the harmful effects of therapy as much as the cancer itself," she stated.
Novel Intratumoral Injection Technology
INT230-6 represents a novel approach to cancer treatment through direct intratumoral injection. The drug combines two established anti-cancer agents - cisplatin and vinblastine sulfate - with a diffusion and cell penetration enhancer molecule called SHAO that facilitates drug dispersion throughout tumors.
The treatment is designed to remain localized within the tumor, resulting in a favorable safety profile while causing release of tumor-specific neoantigens that engage the immune system for systemic anti-tumor effects. Unlike systemic chemotherapy, these effects occur without immunosuppression.
Addressing Aggressive TNBC Subtype
Triple negative breast cancer (搜索) represents approximately 11-17% of all breast cancers, affecting an estimated 56,000 new patients annually in the United States and 420,000 worldwide. TNBC (搜索) is considered more aggressive with poorer prognosis than other breast cancer (搜索) subtypes due to fewer available targeted therapies.
Current standard neoadjuvant treatment achieves pathological complete response rates of 65%, though rates are generally lower in larger tumors or cases with lymph node involvement. The existing Keynote-522 regimen carries significant toxicity, with 80% of patients experiencing grade 3 or higher treatment-related adverse events and a 0.5% treatment-related mortality rate.
Regulatory Pathway and Future Plans
The FDA's Accelerated Approval Program accepts pathological complete response as a surrogate endpoint for high-risk breast cancer (搜索) approvals, potentially enabling faster regulatory approval compared to trials using event-free survival endpoints. Lewis H. Bender, Intensity's CEO, indicated that favorable safety and pathological complete response results could support regulatory discussions for an accelerated approval pathway.
"Should the safety and pCR results remain favorable, we plan to approach regulatory authorities with a Phase 3 study design that could yield a safer, more effective presurgical dosing regimen with good cosmetic outcomes for patients," Bender stated. The company has completed previous clinical studies enrolling over 200 patients and is currently conducting multiple trials across different cancer types.