In the second article of a 2-part series, Aditya Bardia, MD, MPH, discusses the favorable toxicity profile of sacituzumab govitecan for patients with metastatic breast cancer and how he handles neutropenia through the course of treatment.
CASE
Targeted Oncology: Based on the TROPiCS-02 trial (NCT03901339), how does a patient’s HER2 immunohistochemistry status impact results with sacituzumab govitecan (Trodelvy)?
ADITYA BARDIA, MD, MPH: In terms of HER2 [expression]…the drug targets Trop-2, so we would expect that the HER2 results would not matter and that's what was seen [on this trial].1 For patients with a HER2 low tumor or an IHC HER 2 score of 0, the [efficacy] benefit was maintained with sacituzumab govitecan. Overall, in terms of the response rate, it was higher with sacituzumab govitecan compared with standard therapy, [at 21% vs 14%, respectively (HR 1.66; 95% CI, 1.06-2.61), P = .027)].1
What was the toxicity profile seen with this therapy?
The drug has SN-38, so the adverse event [AE] profile would be similar to what you would see with irinotecan [with] myelosuppression, nausea, diarrhea, and alopecia.1 It's the incidence of certain AEs [with sacituzumab govitecan] that are lower compared with irinotecan. [For example], grade 3 diarrhea with irinotecan is about 30%, but with [sacituzumab govitecan] it's 10%.
The advantage of the antibody-drug conjugate [ADC] is that you get more delivery of the payload to tumor cells, so there is a better efficacy and conceptually lower toxicity. [However,] it still does have myelosuppression events, and patients sometimes need granulocyte colony-stimulating [G-CSF] as secondary prophylaxis.1 For nausea, I usually use a 3-drug antiemetic regimen to start with, and then [to help them deal with] diarrhea I usually give patients a prescription of imodium.
What infusion-related reactions, if any, occur with this drug?
Allergic reactions, or infusion related reactions, to sacituzumab govitecan have been described, but they're not very common.1 It's like with any other antibody, where any-grade anaphylactic reactions are quite rare.2 I personally have had a couple of patients with anaphylactic reactions to sacituzumab govitecan, but it's certainly not very common, yet something that can be seen [in patients].
What role does G-CSF play in treating patients who develop neutropenia with this therapy?
In general, I don't use primary prophylaxis with G-CSF, but I do consider secondary prophylaxis with G-CSF if a patient is having a prolonged neutropenia. Rarely, I would consider primary prophylaxis with G-CSF in a patient who is elderly that you're worried that if has neutropenic fever that could be very serious, or the baseline counts are low, but in general, it's more a secondary prophylaxis. Then, it depends whether you want to use short-acting or long-acting G-CSF depending on what you're trying to address [for the patient]. If you want to correct the day 8 neutropenia with sacituzumab govitecan, then use short-acting G-CSF a few days before that, so around day 4 or 5. If you're trying to address it on day 1 of cycle 2 or cycle 3, then with the previous cycle you can use a long-acting G-CSF on day 8, because that will help the next cycle.
References
1. Tolaney S, Bardia A, Marme F, et al. Final overall survival (OS) analysis from the phase 3 TROPiCS-02 study of sacituzumab govitecan (SG) in patients (pts) with hormone receptor–positive/HER2-negative (HR+/HER2–) metastatic breast cancer (mBC). J Clin Oncol. 2023;41(16):1003-1003. doi:10.1200/JCO.2023.41.16_suppl.1003
2. D'Arienzo A, Verrazzo A, Pagliuca M, et al. Toxicity profile of antibody-drug conjugates in breast cancer: practical considerations. EClinicalMedicine. 2023;62:102113. doi:10.1016/j.eclinm.2023.102113
Retrospective Data Highlight Impact of Dose Escalation of Regorafenib in mCRC
May 9th 2024During a Case-Based Roundtable® event, Madappa Kundranda, MD, PhD, discussed recent retrospective studies that looked at outcomes of dose optimization of regorafenib for patients with relapsed/refractory advanced colorectal cancer in the first article of a 2-part series.
Read More
Breast Cancer Leans into the Decade of Antibody-Drug Conjugates, Experts Discuss
September 25th 2020In season 1, episode 3 of Targeted Talks, the importance of precision medicine in breast cancer, and how that vitally differs in community oncology compared with academic settings, is the topic of discussion.
Listen
Key Takeaways From QOL and Use of Steroids With IO-Based RCC Regimens
May 6th 2024During a Case-Based Roundtable® event, Ulka Vaishampayan, MBBS, discussed the safety and quality-of-life data for ipilimumab plus nivolumab in patients with advanced renal cell carcinoma in the second article of a 2-part series.
Read More
NGS and ctDNA Considered in Advanced Breast Cancer After Progression
May 3rd 2024During a Case-Based Roundtable® event, Ruth M. O'Regan, MD, led a discussion on whether to order next-generation sequencing and/or circulating tumor DNA testing for a patient with hormone receptor–positive breast cancer after progression in the first article of a 2-part series.
Read More