Orserdu (elacestrant)

P1, N=124, Recruiting, Stemline Therapeutics, Inc. | Not yet recruiting --> Recruiting

P3, N=4220, Recruiting, Stemline Therapeutics, Inc. | Not yet recruiting --> Recruiting

Estrogen receptor one (ESR1) gene mutations, driving resistance to aromatase inhibitors (AIs), may guide the use of fulvestrant or emerging oral selective estrogen receptor degraders (SERDs) like elacestrant. Targeting mutations like breast cancer gene 1 and 2 (BRCA 1/2) with Poly (ADP-ribose) polymerase (PARP) inhibitors or the PI3K/AKT/mTOR pathway provides therapeutic options. The advent of antibody-drug conjugates (ADCs) like trastuzumab deruxtecan (T-DXd) and novel agents targeting Trophoblast cell surface antigen-2 (Trop-2) introduces further complexity, underscoring the need for early intervention targeting specific genomic alterations in metastatic BC.

In this study, we employed formaldehyde cross-linking followed by ERα immunoprecipitation and mass spectrometry to reveal that fulvestrant, the first FDA-approved SERD, induces the interaction between ERα and SUMO E3 ligases PIAS1 and PIAS2. In addition, raloxifene (a SERM) and elacestrant (the first FDA-approved oral SERD) were identified as compounds that similarly induce ERα SUMOylation and inhibit its chromatin interaction. Our findings reveal a mechanism by which select ERα inhibitors disrupt ERα function through SUMOylation, offering insights for the development of next-generation ERα-targeted therapies.

P1, N=124, Not yet recruiting, Stemline Therapeutics, Inc.

P2, N=176, Recruiting, German Breast Group | Not yet recruiting --> Recruiting | Trial completion date: Mar 2028 --> Dec 2028 | Initiation date: Mar 2024 --> Oct 2024 | Trial primary completion date: Mar 2028 --> Dec 2028

In the liquid biopsies, we detected ESR1 mutations in 42 cases (25.9%) and ERBB2 mutations in six cases (3.7%), arguing for a change in therapy to fulvestrant, elacestrant, or neratinib. Furthermore, 17 cases had detectable TP53 mutations, associated with resistance against endocrine therapy. We conclude that liquid biopsy testing is a noninvasive, sensitive, and helpful method to optimize therapeutic decisions in metastatic BC.

P3; Active, not recruiting --> Completed

The most interesting finding is that compound B16 exhibited significant degradation of ERα at 5 μM but didn't show antiproliferative activity at high concentrations in MCF-7 and T47D cells. Compound B16 may serve as an ER probe to investigate ER status in ER positive breast cancer cells.

Oral SERDs constitute an exciting new drug class. Ongoing and future research will further refine the role of these drugs next to standard endocrine treatments and targeted therapies.

The results showed that all the compounds displayed good stability. Further, the ADMET results showed that compounds CID58023104 was observed to be deemed a hit compound; hence, CID58023104 and could be optimize, derivatize, and explore for further development as an anti-coronavirus agent targeting SARS-COV-2 main protease.

More recently, oral SERDs have been tested in patients with early hormone receptor positive breast cancer, although their impact on survival and in this curative setting compared to standard endocrine therapy still needs to be elucidated. The best timing and duration of SERD administration and specific biomarkers in (neo)adjuvant setting remain largely unknown.

Molecular profiling allowed the identification of ESR1Y537S, in an aggressive prolactinoma. ESR1Y537S was not detected early in the course of the disease and is likely conferring tumor aggressiveness. This finding emphasizes the significance of estrogen receptor signaling in prolactinomas. It also allowed the use of targeted therapy with successful control of disease progression.

For patients with hormone receptor-positive/human epidermal growth factor receptor 2 (HER2)-negative (HR+/HER2-) metastatic breast cancer (mBC) progressed on first-line endocrine therapy plus a cyclin-dependent kinase 4 and 6 inhibitor (CDK4/6i), fulvestrant, a selective estrogen receptor degrader (SERD) administered intramuscularly, represented the only monotherapy option until the approval of elacestrant. However, in Europe, the access to this recommended drug depends on the decision of the National Health Authorities of each state. In this communication, we describe the main results and implications of the EMERALD trial, in the context of the biomarker-driven algorithm for patients with HR+/HER2- mBC progressed on CDK4/6i, and conclude that a subgroup of patients with ESR1-mutant tumors and specific clinical features can really derive a clinically meaningful benefit from elacestrant, sparing access to more toxic combination approaches and preserving the quality of life.

P1/2, N=49, Active, not recruiting, Carrick Therapeutics Limited | Recruiting --> Active, not recruiting

P=N/A, N=350, Recruiting, SciClone Pharmaceuticals

Ongoing clinical trials assessing elacestrant and other SERDs will yield data that might aid clinicians in determining the optimal selection and order of endocrine treatment drugs for ER+ breast cancer. The integration of targeted and immunotherapeutic agents with traditional chemotherapy represents a pivotal shift in Breast Cancer treatment, moving towards more personalized and effective regimens.

P1/2, N=68, Recruiting, Stemline Therapeutics, Inc. | N=106 --> 68

Duration of prior ET+CDK4/6i ≥12 months in mBC was associated with a clinically meaningful improvement in PFS for elacestrant compared to SOC and was consistent across all subgroups evaluated in patients with ER+, HER2-, ESR1-mutated tumors.

The primary endpoint is distant metastasis free survival and secondary endpoints are invasive disease-free survival, relapse-free survival, overall survival, safety and quality of life. Recruitment started in December 2023 in Belgium and is planned to open in 11 more countries in 2024: Cyprus, France, Germany, Greece, Italy, Ireland, the Netherlands, Portugal, Spain, Sweden, and Switzerland.

P3, N=240, Not yet recruiting, MedSIR | Initiation date: Jun 2024 --> Sep 2024

P3, N=4220, Not yet recruiting, Stemline Therapeutics, Inc.

P1, N=16, Recruiting, Stemline Therapeutics, Inc. | Not yet recruiting --> Recruiting | Initiation date: Jan 2024 --> Mar 2023

The widespread adoption of fulvestrant in the treatment of ER+ breast cancer continues to stimulate research into orally bioavailable SERDs and SERCAs. A number of molecules have entered clinical development and, although some have been discontinued, a cohort of potential new treatments have generated encouraging efficacy and safety data. Notably, the first example of an oral SERD, elacestrant, has now been approved by the FDA and EMA, providing further encouragement for this class of targeted therapies.

Aromatase inhibitors (AI), including anastrozole, letrozole and exemestane, suppress estrogen production...Tamoxifen and AI are widely used both in early- and advanced-stage disease, while fulvestrant is used as a single agent or in combination with other agents like the cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors (palbociclib, abemaciclib, ribociclib) or alpelisib for advanced-stage disease. Currently, SERDs are recognized as an effective therapeutic approach for the treatment of ER-positive breast cancer, showing proficiency in reducing and blocking ER signaling. This review aims to outline the ongoing development of novel oral SERDs from a practical therapeutic perspective, enhancing our understanding of the mechanisms of action underlying these compounds.

"Guardant Health, Inc...announced certification for its Guardant360 CDx blood test under the European Union’s In Vitro Diagnostic Regulation (IVDR 2017/746). The certification from TÜV SÜD Product Service is for tumor mutation profiling in patients with any solid cancerous tumor and for companion diagnostic indications to identify patients who may benefit from certain targeted therapies for advanced non-small cell lung cancer and breast cancer....Under the IVDR, Guardant360 CDx is certified as a companion diagnostic to identify patients with non-small cell lung cancer who may benefit from treatment with TAGRISSO (osimertinib), RYBREVANT (amivantamab), or LUMYKRAS (sotorasib), and advanced breast cancer patients with ESR1 mutations who may benefit from treatment with ORSERDU (elacestrant)."

No abstract available

Elacestrant, a second-line ER degrader, increases overall free-survival in patients with resistant breast cancer and ESR1Y537S...Abstracts presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.

Background: ESR1 and PIK3CA mutations inform the use of targeted agents such as alpelisib (A), elacestrant (E), and capivasertib in patients (pts) with HR+/HER2- metastatic breast cancer (mBC). The rate of ESR1 and PIK3CA co-mutation in this cohort was consistent with the reported literature. mTTNT was significantly longer with A + ET compared to E, but real world outcomes on E remain immature with one-third of pts still on E at the time of analysis. A limitation of this study was the small sample size.

We observed an increase in cfDNA testing at the start of 2023 which aligns with the FDA approval of elacestrant. We observed variation by site and individual providers that warrants further exploration to improve cfDNA testing in MBC pts at Mayo Clinic.

P3, N=240, Not yet recruiting, MedSIR

Until 2023, fulvestrant was the only approved SERD; fulvestrant is administered intramuscularly, and in some cases may also have limited efficacy in the setting of certain ESR1 mutations. Elacestrant's recent approval sheds light on the use of biomarkers such as ESR1 to gauge a tumor's endocrine sensitivity. Ongoing therapeutic and correlative biomarker studies will offer new insight and expanding treatment options for patients with advanced breast cancer.

P2, N=80, Recruiting, Stemline Therapeutics, Inc. | Trial primary completion date: Feb 2024 --> Feb 2025

However, following the breast cancer-specific FDA approvals of alpelisib+fulvestrant for PIK3CA-mutant disease in 2019 and elacestrant for ESR1-mutant disease in 2023, a significant shift in Level 1 actionability was observed between EUR (45%) and AFR (34%) attributed in part to the paucity of PIK3CA (26.3% vs. 36.2% in EUR) and ESR1 (4.1% vs. 7.5% in EUR) oncogenic alterations in AFR.We further observed AFR with CRC to have lower prevalence of MSI-H (5.8% vs.10.7% in EUR), TMB (12.5% vs. 18.8% in EUR) and BRAF V600E (5.1% vs. 9% in EUR). Correspondingly, in 2023, 16.4% of AFR with CRC have Level 1 alterations compared to 25.4% of EUR. Moreover, while AFR have higher rates of KRAS mutations (57.2% vs. 42.6% in EUR), they have a lower prevalence of the standard care biomarker KRAS G12C (3.4% vs. 7% of KRAS-mutant CRC in EUR) further exacerbating the disparities in CRC clinical actionability.Taken together, here we demonstrate that a significant disparity exists in the clinical actionability landscape of AFR with cancer compared to EUR, largely due to differences in relative mutational frequencies of Level 1 genomic alterations.

Fulvestrant is the first approved SERD with proven efficacy and good tolerability in clinical practice...Elacestrant is an orally bioavailable SERD that has been recently approved by the FDA for postmenopausal women with ER+, human epidermal growth factor receptor 2-negative (HER2-), estrogen receptor 1 (ESR1)-mutated advanced or metastatic breast cancer with disease progression following at least one line of endocrine therapy. Other molecules of the same class currently tested in clinical trials are amcenestrant, giredestrant, camizestrant, and imlunestrant. The current review article offers a detailed pharmacological perspective of this emerging drug class, which may help with their possible future clinical applications.

The approval of elacestrant in ER+, HER2- advanced or metastatic breast cancer was restricted to patients with ESR1 mutations. Benefit-risk assessment in the ESR1-mut subgroup was favorable on the basis of a statistically significant improvement in PFS in the context of an acceptable safety profile including no evidence of a potential detriment in OS. By contrast, the benefit-risk assessment in patients without ESR1 mutations was not favorable. Elacestrant is the first oral estrogen receptor antagonist to receive FDA approval for patients with ESR1 mutations.

P2, N=48, Recruiting, SOLTI Breast Cancer Research Group | Not yet recruiting --> Recruiting

P3; Not yet recruiting --> Recruiting

Novel endocrine options including oral selective estrogen receptor down-regulators (SERDs) are in late phases of development, with elacestrant being the first oral SERD to be approved for ESR1-mutant mBC...Trastuzumab deruxtecan offers a novel therapeutic option for patients with HR+/HER2-low mBC and sacituzumab govitecan is a novel therapeutic option for patients with HR+/HER2- mBC, including those with unmet treatment need in the later-line endocrine-refractory setting. Data gaps still exist regarding optimal sequencing of these novel agents; additional studies into mechanisms of resistance in the metastatic setting would provide further insights. Herein, we describe the current treatment options for HR+/HER2- mBC, including the latest practice-impacting data, and provide commentary on future directions.

P2, N=176, Not yet recruiting, German Breast Group

ELA led to an incremental cost-effectiveness ratio (ICER) of $8,672,360/quality-adjusted life year (QALY) gained compared with SOC in the overall population and $2,900,560/QALY gained compared with fulvestrant (FUL) in the ESR1(estrogen receptor 1) mutation subgroup. The two ICERs of ELA were significantly higher than the willingness-to-pay (WTP) threshold values of $150,000/QALY. ELA was not cost-effective for the second-/third-line treatment of patients with ER+/HER2-A/MBC compared with SOC in the US.

P1/2, N=106, Recruiting, Stemline Therapeutics, Inc.