Emerging Data Showcases Promising Advancements for Patients With HER2-Low Breast Cancer

The 2022 San Antonio Breast Cancer Symposium highlighted promising advances in breast cancer treatments across multiple settings and disease types, including for patients with HER2-low and hormone receptor–negative disease.

Moreover, according to Loyda Braithwaite, MSN, RN, AGPCNP-BC, AOCNP, some data that were presented may hold the potential to open doors for patients with hard-to-treat diseases.

Braithwaite, who is an Oncology Nurse Practitioner at the University of Wisconsin Carbone Cancer Center, recently sat down with Oncology Nursing News® to offer her perspective on key trials that were presented at this year’s symposium.

Oncology Nursing News®: What stood out to you about this year’s symposium?

Braithwaite: What I found very interesting is how much we are discovering within the HER2-positive population. This is [a space] that has been kind of stagnant for a few years, but now more data from the DESTINY-Breast02 [NCT03523585], DESTINY-Breast03 [NCT03529110] [trials, are] confirming what we previously knew with TDX-d [fam-trastuzumab deruxtecan-nxki (Enhertu)]. I think this is very informative. Data are maturing more, and we’re seeing the advantages in progression-free survival [PFS] for our patients with HER2-positive metastatic breast cancer. When it comes to the metastatic setting, sometimes, we are left with [few] options, but I think [the data from these trials] are good and interesting.

As time goes, we learn more. As we treat more patients with TDX-d, [we are] more aware of some of the adverse effects, particularly with pulmonary involvement, or [interstitial lung disease] ILD. When CDK4/6 inhibitors came, we knew that there was the risk of ILD and pulmonary compromise, but now with more patients being treated with TDX-d, I think those rates have a risk of increasing or being more common, so we have to be on top of that early on.

On top of the ILD, [another] severity was the left ventricular dysfunction [LVEF] for patients. As clinicians, we have to be on the lookout for potentially life threatening or pretty severe [adverse effects, such as] ILD and LVEF dysfunction.

Were there any other trials that are promising to open doors for hard-to-treat populations?

I found sacituzumab govitecan-hziy [Trodelvy], in TROPiCS-02 [NCT03901339] for patients with hormone receptor–positive disease [to be interesting]. We’ve known about [this drug’s efficacy] for triple negative disease in the metastatic setting, but now we’re seeing it for patients with hormone receptor–positive [disease] too. We saw some data that, regardless of TROP-2 expression, there may be some benefit for these patients as well, in terms of PFS. This is just shining light on potentially more treatments for patients with hormone receptor–positive breast cancer and which we didn’t have in the past.

Another trial that I think was very fascinating was the TRIO-US B-12 TALENT trial [NCT04553770]. That was looking at whole new world of HER2-low. To me, this is magnificent because it’s opening this door. [We] have all these patients [whose HER2-low disease] we can [now] target.

This particular trial was looking into TDX-d alone and TDX-d with endocrine therapy for patients with HER2-low and hormone receptor–positive [disease] in the neoadjuvant setting. Before, we had options with neoadjuvant therapy and endocrine therapy alone, and [we’d] see how it responds, but sometimes we were missing those people that may have been high risk. [Although] the data is still not fully mature, it seems promising that we may be able to, in the future, use TDX-d in the neoadjuvant setting—potentially as a single therapy, or in a combination with [another] therapy. I really liked that.

How do you interpret the data surrounding oral SERDS? Do they hold potential to change practice?

Oral [selective estrogen receptor degraders] SERDs were a big thing in San Antonio this year. [Although] the AMEERA-3 [NCT04059484] didn’t meet its primary end point, the EMERALD trial [NCT03778931] with elacestrant did have some positive data that may be promising. In combination with a CDK4/6 inhibitor it looks promising, as well.

For decades, we have had fulvestrant but administration [was difficult, so I believe] SERDs could be practice changing. If we had oral SERDs approved—when it comes to having an extra line of endocrine therapy for patients or an option that does not require traveling for patients—access would be better. [Right now,] patients commute every month to get a health care professional to administer an injection.

As the data matures, I can only imagine other trials will come down the pipe[line]. So, to me, this is very exciting from the clinician perspective, but also from the patient perspective, to think about the accessibility [options] that we’re going to have to treat them.