Potential Benefits of GLP-1 Agonists in Reducing Chemotherapy-Related Toxicities in Breast Cancer

At the San Antonio Breast Cancer Symposium, in San Antonio, Elvis Obomanu, MBBS, LMCC, presented hypothesis-generating findings exploring the potential role of GLP-1 agonists in reducing chemotherapy-related toxicities among patients with breast cancer. Drawing from retrospective data, Obomanu highlighted clinically meaningful reductions in treatment-limiting adverse events, including neutropenia, cardiomyopathy, and neuropathy—key drivers of dose reductions and discontinuations in breast cancer chemotherapy. He emphasized that reductions in neutropenia may lower infection risk, while improved cardiac outcomes could translate to fewer hospitalizations and reduced morbidity.

Pharmacy Times: The magnitude of benefit seen across multiple side effects is clinically meaningful. Which toxicity reductions do you think have the greatest potential to change oncology supportive-care protocols if confirmed in prospective trials?

Elvis Obomanu, MBBS, LMCC: So there are several benefits that we found in our study, but I think, importantly, we have to take into consideration which side effects have led to more dose reductions or discontinuations of chemotherapy agents in breast cancer patients. One of them is neutropenia, right? And if this were to be validated, the fact that it reduces the side effect of neutropenia is something that is really meaningful. And this is because with neutropenia comes infections in most cases. So if this were done, that would also be fine.

The other thing, again, is its effect on the heart, right? Our study did show that there was a significant reduction in cardiomyopathies in patients on GLP-1s, and with this beneficial effect, hospitalizations may be reduced in this patient. The morbidity in this patient may also be reduced, and that’s why we’re looking for that.

And something, again, that I did not mention is neuropathies. Neuropathies have led to significant discontinuations of chemotherapy in breast cancer patients. And so if our findings are validated by prospective clinical studies or randomized controlled trials, this will prove to be the most beneficial effect of the GLP-1 medications.

Pharmacy Times: This study used a large real-world dataset with matched cohorts. What key questions should future prospective trials address to determine whether GLP-1 RAs could be formally incorporated into breast cancer supportive-care guidelines?

Obomanu: Our presentation today was basically hypothesis generation. It means that there is ample room for more studies to be generated from what we did. Now, part of the clinical questions that should be generated from this is number one: is the effect across all stages of breast cancer? That’s number one, because our study was basically across all. So if we were to do larger studies or prospective trials, would this effect be seen across all of the stages?

Number two is that one of the limitations of our own study was that we were not specific about the dosages of the GLP medications. So at what dose are these medications really beneficial, such that we can see this reduction in side effects? And something, again, that’s very important is whether these medications should be administered concurrently with what’s called chemotherapy or before chemotherapy.

And finally, our study was in patients who were either diabetic or obese. So the question is, in non-diabetic or non-obese patients, would you find significant clinical benefits from prescribing GLP-1 agonists? And of course, what will be the cost implications in this population if GLP-1 agonists are prescribed?