Researchers based out of Icahn School of Medicine at Mount Sinai, NY, USA say that a combination of four targeted therapies could eventually replace chemotherapy for Herceptin receptor-positive breast cancer. The team of oncologists and scientists, headed by Professor Amy Tierson, MD, reported in the Journal of the National Cancer Institute that some women with HR+ and HER2 + breast cancer might be able to swap harsh chemo treatments for a cocktail of anastrozole, palbociclib, trastuzumab, and pertuzumab.
A New Regimen for HR+/HER2+ breast Cancers?
Tierson explained in a press release, ‘This study demonstrates that a chemotherapy-free treatment approach can produce durable responses while maintaining a manageable safety profile for many patients with this subtype of metastatic breast cancer.’ She continued, ‘Although these findings need to be confirmed in larger randomized clinical trials, they suggest that some patients may eventually have an effective alternative to chemotherapy as their first treatment.’
The researchers demonstrated in early stage clinical trials that pairing endocrine therapy with drugs that target key cancer driving molecular processes benefited 97% of participants in the first six months of treatment. In around half of patients, this treatment regimen held off progression of the disease for more than two years, with 93% of women surviving a median of 39 months.
Chemotherapy is an effective treatment for many women with HR+ breast cancer, but for others the side effects can be a problem. ‘The challenge in treating this type of breast cancer is balancing effectiveness with quality of life,’ said Rima Patel, MD, Assistant Professor of Medicine (Hematology and Medical Oncology) at the Icahn School of Medicine and first author of the study. ‘Many patients, particularly older adults or those with other medical conditions, may not be ideal candidates for chemotherapy. A targeted regimen that can be given primarily through oral medication and subcutaneous injection could offer a more convenient option while reducing some of chemotherapy’s burden.’
A Preliminary Trial
The team recruited 29 women with HER2 or HR-positive breast cancer to take part in a single arm clinical trial. The women agreed to forgo traditional chemotherapy and adjuvant therapies to see if combining anastrozole, palbociclib, trastuzumab, and pertuzumab could help to manage their condition. The trial design did not compare this novel treatment regimen with existing approaches. This project is in its early stages; Tierson and her trainees are still gathering preliminary data to figure out if this strategy has legs. Once they have an idea of whether the combination treatment is helpful and relatively safe, they will be able to move to randomized controlled clinical trials. The next step will be to see how it stacks with the usual treatments – is it as effective?
The side effects appear to be less troublesome than those of traditional therapies, with only one patient discontinuing treatment. Common adverse events included anaemia, low white blood cell counts and diarrhoea.
Sources
Patel R, Kwa M, Klein P, et al. A multicenter, phase 1/2 trial of anastrozole, palbociclib, trastuzumab, and pertuzumab in hormone receptor–positive, HER2-positive metastatic breast cancer (ASPIRE). J Natl Cancer Inst. Published online July 30, 2026:djag256. doi:10.1093/jnci/djag256
Mount Sinai study finds chemotherapy-free treatment shows promise for some patients with metastatic breast cancer. EurekAlert! Accessed September 29, 2026. https://www.eurekalert.org/news-releases/1140886
