Elinzanitant, a neurokinin-targeted therapy, has been shown to reduce vasomotor symptoms compared to placebo. These symptoms are one of the reasons some of my patients discontinue aromatase inhibitor (AI) therapy, so Elinzanitant presents a promising alternative to help manage these side effects. Additionally, Fezolinetant is already approved and available on the market.
Women receiving endocrine therapy for hormone receptor (HR)–positive breast cancer or its prevention among those at high risk for breast cancer commonly have vasomotor symptoms. Data are lacking on the effects of elinzanetant, a neurokinin-targeted therapy shown to be effective in treating vasomotor symptoms, in this population.
We performed a phase 3 trial involving women 18 to 70 years of age with moderate-to-severe vasomotor symptoms associated with endocrine therapy for HR-positive breast cancer or its prevention. Women were randomly assigned in a 2:1 ratio to receive once-daily elinzanetant at a dose of 120 mg for 52 weeks or once-daily placebo for 12 weeks followed by once-daily elinzanetant at a dose of 120 mg for 40 weeks. The primary end points were the change in the mean daily frequency of moderate-to-severe vasomotor symptoms from baseline to week 4 and to week 12. Research Summary Elinzanetant for Vasomotor Symptoms from Endocrine Therapy
A total of 316 participants were assigned to the elinzanetant group and 158 to the placebo–elinzanetant group. At baseline, the mean daily frequency of moderate-to-severe vasomotor symptoms was 11.4 episodes (95% confidence interval [CI], 10.7 to 12.2) in the elinzanetant group and 11.5 episodes (95% CI, 10.5 to 12.5) in the placebo–elinzanetant group. At week 4, the mean change from baseline in the mean daily frequency of moderate-to-severe vasomotor symptoms was −6.5 episodes (95% CI, −7.2 to −5.8) among those who were receiving elinzanetant and −3.0 episodes (95% CI, −3.9 to −2.2) among those who were receiving placebo (least-squares mean difference, −3.5 episodes; 95% CI, −4.4 to −2.6; P
Elinzanetant led to a significantly lower frequency of vasomotor symptoms associated with endocrine therapy than placebo. (Funded by Bayer; OASIS-4 ClinicalTrials.gov number, NCT05587296.)
Our site participated in this study, where patients were tested for ESR1 mutations via circulating tumor DNA (ctDNA). Those who tested positive were switched to camizestrant (Cami), which demonstrated improved progression-free survival.
Vepdegestrant is an oral proteolysis-targeting chimera (PROTAC) estrogen receptor (ER) degrader that directly utilizes the ubiquitin–proteasome system. It was compared to fulvestrant in patients who had received one prior line of hormonal therapy with a CDK4/6 inhibitor. Among patients with ESR1 mutations, Vepdegestrant demonstrated a median progression-free survival (PFS) of 5.0 months versus 2.1 months with fulvestrant. In the overall population, the median PFS was 3.8 months for Vepdegestrant and 3.6 months for fulvestrant, indicating that the drug showed particular efficacy in tumors harboring ESR1 mutations.
The INAVO120 trial evaluated inavolisib + palbociclib–fulvestrant vs placebo + palbociclib–fulvestrant in patients with PIK3CA-mutated, HR+/HER2– advanced breast cancer progressing on or shortly after adjuvant endocrine therapy (ET). Inavolisib significantly improved overall survival (OS) (34.0 vs 27.0 mo) and progression-free survival (PFS) (17.2 vs 7.3 mo), with a higher objective response rate (ORR) (62.7% vs 28.0%) and longer DoR (19.2 vs 11.1 mo). Toxicities were manageable but included more hyperglycemia (63.4%), stomatitis (55.3%), GI, and ocular AEs. Bottom line: this triplet sets a new bar for first-line PIK3CA-mutant HR+ MBC, but we’ll need to stay vigilant about metabolic and mucosal side effects as we bring it into practice.
Adding Palbociclib did not help, revealing that there is no need to continue with different hormonal therapy than the one used in first line. It also added more toxicity.
DON’T omit, there is still a benefit, especially in 6-10% patients.