Advances in Triple-Negative Breast Cancer: From Preventive Vaccines to ADC Approvals Reshape the Treatment Landscape
核心洞察
A phase I trial of a preventive TNBC vaccine targeting a lactation-associated milk protein showed immune responses in 74% of high-risk women and is advancing to phase II.
The FDA has approved two antibody-drug conjugates, Trodelvy and Datroway, as first-line treatments for metastatic TNBC, potentially allowing patients to skip initial chemotherapy.
New research reveals that 30% of recurrent TNBC tumors become hormone receptor-positive, suggesting hormonal therapies like tamoxifen could reduce recurrence risk.
Triple-negative breast cancer (搜索) (TNBC) remains one of the most challenging breast cancer subtypes to treat, defined by the absence of estrogen, progesterone, and HER2 (搜索) receptors. Accounting for roughly 10-15% of all breast cancer diagnoses, TNBC tends to grow and spread faster than other invasive breast cancers, carries a worse prognosis, and has a high likelihood of recurrence. Yet a wave of recent research advances—spanning preventive vaccines, novel immunotherapies, antibody-drug conjugates (ADCs), and fundamental tumor biology discoveries—is reshaping the outlook for patients.
A preventive vaccine moves toward phase II
Among the most promising developments is a preventive TNBC vaccine that elicited an immune response in 74% of women in a phase I trial and is now advancing to a phase II study. The vaccine is designed for individuals at high risk of developing TNBC and builds on research that trains the immune system to distinguish TNBC cells from normal cells.
The target is a milk protein normally produced during lactation that appears in TNBC tumors but not in other breast cancer types. By training the immune system to recognize this protein, the vaccine primes it to attack if the protein resurfaces in tumors.
Immune cell levels may guide treatment intensity
Roberto Leon-Ferre, MD, a breast cancer oncologist at Mayo Clinic, found that patients with early-stage TNBC who had higher levels of tumor-infiltrating immune cells responded better to treatment and had a lower risk of recurrence. "It may be possible in the future, if additional research confirms this, that a subset of these people may actually be able to avoid chemotherapy altogether, or at least receive a less-intensive chemotherapy," Leon-Ferre said. He cautioned, however, that more research is needed before treatment decisions can be based on immune cell levels.
Currently, chemotherapy plus the immune checkpoint inhibitor Keytruda (pembrolizumab) is the standard of care for early-stage TNBC. A new study suggests that camrelizumab, an immune checkpoint inhibitor currently approved for liver cancer in the United States, may also benefit early-stage TNBC patients. Women who received camrelizumab plus chemotherapy before surgery demonstrated a better treatment response than those receiving chemotherapy alone. If approved for breast cancer, camrelizumab would expand the treatment arsenal for early-stage disease.
ADC approvals transform metastatic TNBC care
The FDA has approved two antibody-drug conjugates as first-line treatments for people with metastatic TNBC: Trodelvy (sacituzumab govitecan-hziy) and Datroway (datopotamab deruxtecan, commonly called Dato-DXd). Historically, patients with metastatic TNBC received chemotherapy and immunotherapy depending on tumor type, with ADCs reserved for those whose tumors recurred or failed to respond to other treatments. With these new approvals, eligible patients may be able to forgo chemotherapy in their first round of treatment.
Both Trodelvy and Datroway are approved for patients with metastatic TNBC who are not eligible for Keytruda. Trodelvy can also be used in combination with Keytruda for those with PD-L1 (搜索)-positive metastatic TNBC. Both drugs outperformed chemotherapy in clinical trials.
Hormone receptor conversion in recurrent tumors
One reason TNBC is notoriously difficult to treat is its lack of hormone receptors, rendering hormonal therapies ineffective. However, researchers recently discovered that when TNBC tumors recur, 30% test positive for hormone receptors. This finding suggests that some TNBC tumors may harbor low levels of hormone receptors at initial diagnosis. If confirmed, hormonal therapies such as tamoxifen could be incorporated into treatment strategies to reduce recurrence risk and potentially prevent this receptor conversion.
Tumors hijack energy from fat cells
A study in cells and mice led by Andrei Goga, MD, PhD, a medical oncologist at the University of California San Francisco, has uncovered a novel survival strategy employed by TNBC: tumors siphon energy from nearby fat cells through tiny tunnels. When researchers blocked these tunnels, tumor growth halted. "The cancer cells suck energy from fat cells using tiny tunnels, and the energy helps the tumors grow," the research revealed. Further investigation is needed to determine whether TNBC tumor cells interact with fat in the same manner in humans. If they do, targeting these intercellular tunnels could represent an entirely new therapeutic approach.
Genetic insights into racial disparities
TNBC disproportionately affects Black women—nearly 20% of breast cancers diagnosed in Black women are TNBC, compared to lower rates in white women. New research has identified a potential genetic contributor: the TRIM37 (搜索) gene, a breast oncogene that produces proteins facilitating tumor formation, spread, and chemotherapy resistance. Black women are more likely to carry a small mutation in TRIM37 that causes the gene to overproduce these problematic proteins. While anyone with TNBC could have an overactive TRIM37 gene, this finding may help explain the observed racial disparities in TNBC incidence.
The broader TNBC landscape
TNBC is more common in women younger than 40, in Black women, and in those with certain genetic mutations. Signs and symptoms mirror those of other breast cancers—including a new breast lump, swelling, skin dimpling, nipple retraction or discharge, and swollen lymph nodes—though some individuals may be asymptomatic. Approximately 1 in 8 women in the U.S. will be diagnosed with breast cancer in their lifetime, with TNBC representing 10-15% of those diagnoses.
From preventive vaccination strategies to metabolic vulnerabilities and expanding therapeutic options, the TNBC research pipeline reflects a deepening understanding of this aggressive disease. While many of these advances remain investigational, the trajectory points toward a future with more personalized, less toxic, and increasingly effective treatment regimens.