Elacestrant hydrochloride

Data spans seven presentations across both solid tumors and hematologic malignancies , providing updates on the potential benefit these therapies may bring to patients. Data from the elacestrant plus capivasertib regimen of the ELEVATE study will be presented underscoring its potential in combination settings in mBC, along with updates from the robust elacestrant clinical development program, including its potential role as a monotherapy option in adjuvant breast cancer. Stemline’s partner, Karyopharm Therapeutics, will present a late-breaking oral presentation from the phase 3 SENTRY trial of selinexor in myelofibrosis FLORENCE, Italy and NEW YORK, May 14, 2026 (GLOBE NEWSWIRE) -- The Menarini Group (“Menarini”), a leading international pharmaceutical and diagnostics company, and Stemline Therapeutics, Inc. (“Stemline”), a wholly-owned subsidiary of the Menarini Group, focused on bringing transformational oncology treatments to cancer patients, announced that new data related to ORSERDU ® (elacestrant) and ELZONRIS ® (tagraxofusp-erzs) will be presented at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting. New data exploring the safety and preliminary efficacy of elacestrant in combination with capivasertib in patients with ER+/HER2- PI3K/AKT/PTEN- pathway altered metastatic breast cancer (mBC) from the phase 1 ELEVATE study will be presented. Additional details on ongoing studies of elacestrant in combination, in the advanced setting, will be shared: ADELA (pivotal phase 3 combination with everolimus); ELECTRA (phase 1b/2 combination with abemaciclib in patients with brain metastases); and CAPELA (phase 2 combination with capecitabine). Lastly, an update from the ELEGANT study, exploring elacestrant as adjuvant treatment in node-positive early breast cancer with high risk of recurrence, will be presented at the congress. Also accepted for presentation is new phase 2 tagraxofusp combination data in patients with blastic plasmacytoid dendritic cell neoplasm (BPDCN), which will be presented by Naveen Pemmaraju, MD, Professor, Department of Leukemia, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center. Additionally, Stemline’s partner, Karyopharm Therapeutics, will present a late-breaking oral presentation from the phase 3 SENTRY trial of selinexor in JAKi naïve patients with myelofibrosis (MF). Selinexor is marketed as XPOVIO ® in the U.S. by Karyopharm Therapeutics, and as NEXPOVIO ® in the EU by Stemline. “The extensive oncology data that will be presented, encompassing both solid tumors and hematologic malignancies, highlights our dedication to tackling the most difficult-to-treat cancers with high unmet needs,” said Elcin Barker Ergun, CEO of the Menarini Group. “Our focus remains on accelerating innovation to provide transformational, targeted therapies that offer meaningful advances to patients and the healthcare communities dedicated to their care.” See below for full details of upcoming presentations: 2026 American Society of Clinical Oncology (ASCO) Annual Meeting Lead Author​ Abstract Title and ID​ Presentation Details​ Elacestrant Wassim McHayleh ​ Elacestrant in combination with capivasertib in patients with ER+/HER2- advanced breast cancer: Update from ELEVATE, a phase 1b/2 open-label, umbrella study Abstract: 1098 June 1, 2026; 1:30 – 4:30 PM CT Poster Board 212 Aditya Bardia ELEGANT: Elacestrant versus standard endocrine therapy in women and men with node-positive, estrogen receptor-positive (ER+), HER2-negative (HER2-), early breast cancer with high risk of recurrence in a global, multicenter, randomized, open-label phase 3 study Abstract: TPS1153 June 1, 2026; 1:30 – 4:30 PM CT Poster Board 262a Antonio Llombart-Cussac ADELA: A double-blind, placebo-controlled, randomized phase 3 trial of elacestrant + everolimus versus elacestrant + placebo in ER+/HER2- advanced breast cancer patients with ESR1-mutated tumors progressing on endocrine therapy + CDK4/6i* # Abstract: TPS1154 June 1, 2026; 1:30 – 4:30 PM CT Poster Board 262b Nuhad Ibrahim ELECTRA: An open-label multicenter, phase 1b/2 study of elacestrant in combination with abemaciclib in patients with brain metastasis from ER+/HER2- breast cancer Abstract: TPS1155 June 1, 2026; 1:30 – 4:30 PM CT Poster Board 263a Kristina Fanucci CAPELA: A phase II multicenter open-label randomized study of capecitabine in combination with elacestrant versus capecitabine alone in advanced estrogen receptor (ER)–positive breast cancer (TBCRC 070)* Abstract: TPS1156 June 1, 2026; 1:30 – 4:30 PM CT Poster Board 263b Tagraxofusp Naveen Pemmaraju A Phase II Trial of Tagraxofusp, Hyper-CVAD, and Venetoclax for Patients with Newly Diagnosed or Relapsed/Refractory BPDCN* Abstract: 6502 Oral Presentation June 2, 2026; 10:09 – 10:21 am CT Selinexor John Mascarenhas Selinexor plus ruxolitinib in JAK inhibitor–naïve myelofibrosis: Phase 3 SENTRY trial* Abstract: LBA6500 Oral Presentation June 2, 2026; 9:45 am – 12:45 pm CT *Denotes investigator sponsored research or collaborative research #The ADELA study is a pivotal study co-sponsored with MEDSIR About The Elacestrant Clinical Development Program Elacestrant is also being investigated in several company-sponsored clinical trials in breast cancer disease, alone or in combination with other therapies. ELEGANT ( NCT06492616 ) is a phase 3 trial evaluating the effectiveness of elacestrant versus standard endocrine therapy in women and men with node-positive, ER+, HER2- early breast cancer with high risk of recurrence. ADELA ( NCT06382948 ) is a phase 3 randomized, double-blinded trial evaluating elacestrant in combination with everolimus in patients with ER+, HER2- mBC with ESR1-mut tumors. ELEVATE ( NCT05563220 ) is a phase 1b/2 clinical trial evaluating the safety and efficacy of elacestrant combined with alpelisib, everolimus, capivasertib, palbociclib, ribociclib or abemaciclib. ELECTRA ( NCT05386108 ) is an open-label phase 1b/2, multicenter study evaluating elacestrant in combination with abemaciclib in patients with ER+, HER2- breast cancer. The phase 2 portion evaluates this treatment regimen in patients with brain metastases. ELCIN ( NCT05596409 ) is a phase 2 trial evaluating the efficacy of elacestrant in patients with ER+, HER2- advanced/metastatic breast cancer who received one or two prior hormonal therapies and no prior CDK4/6 inhibitors in the metastatic setting. Elacestrant is also being evaluated in additional investigator-led trials, in trials conducted in collaboration with other companies, in metastatic breast cancer as well as in early disease. About ORSERDU ® (elacestrant) U.S. Indication: ORSERDU (elacestrant), 345 mg tablets, is approved by the U.S. Food & Drug Administration (FDA) for the treatment of postmenopausal women or adult men with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative, ESR1-mutated advanced or metastatic breast cancer with disease progression following at least one line of endocrine therapy. Full prescribing information for the U.S. can be found at Important Safety Information, ORSERDU ® Warning and Precautions Dyslipidemia : Hypercholesterolemia and hypertriglyceridemia occurred in patients taking ORSERDU at an incidence of 30% and 27%, respectively. The incidence of Grade 3 and 4 hypercholesterolemia and hypertriglyceridemia were 0.9% and 2.2%, respectively. Monitor lipid pro to starting and periodically while taking ORSERDU. Embryo-Fetal Toxicity : Based on findings in animals and its mechanism of action, ORSERDU can cause fetal harm when administered to a pregnant woman. Advise pregnant women and females of reproductive potential of the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during treatment with ORSERDU and for 1 week after the last dose. Advise male patients with female partners of reproductive potential to use effective contraception during treatment with ORSERDU and for 1 week after the final dose. Adverse Reactions Serious adverse reactions occurred in 12% of patients who received ORSERDU. Serious adverse reactions in >1% of patients who received ORSERDU were musculoskeletal pain (1.7%) and nausea (1.3%). Fatal adverse reactions occurred in 1.7% of patients who received ORSERDU, including cardiac arrest, septic shock, diverticulitis, and unknown cause (one patient each). The most common adverse reactions ( > 10%) , including laboratory abnormalities, of ORSERDU were musculoskeletal pain (41%), nausea (35%), increased cholesterol (30%), increased AST (29%), increased triglycerides (27%), fatigue (26%), decreased hemoglobin (26%), vomiting (19%), increased ALT (17%), decreased sodium (16%), increased creatinine (16%), decreased appetite (15%), diarrhea (13%), headache (12%), constipation (12%), abdominal pain (11%), hot flush (11%), and dyspepsia (10%). Drug interactions Concomitant use with CYP3A4 Inducers and/or inhibitors : Avoid concomitant use of strong or moderate CYP3A4 inhibitors with ORSERDU. Avoid concomitant use of strong or moderate CYP3A4 inducers with ORSERDU. Use in specific populations Lactation : Advise lactating women to not breastfeed during treatment with ORSERDU and for 1 week after the last dose. Hepatic Impairment : Avoid use of ORSERDU in patients with severe hepatic impairment (Child-Pugh C). Reduce the dose of ORSERDU in patients with moderate hepatic impairment (Child-Pugh B). The safety and effectiveness of ORSERDU in pediatric patients have not been established. To report SUSPECTED ADVERSE REACTIONS, contact Stemline Therapeutics, Inc. at 1-877-332-7961 or FDA at 1-800-FDA-1088 or . Elacestrant is also being investigated in several clinical trials in metastatic breast cancer disease, alone or in combination with other therapies: ELEVATE ( NCT05563220 ); ELECTRA ( NCT05386108 ); and ELCIN ( NCT05596409 ). Elacestrant is also being evaluated in early breast cancer disease. About ELZONRIS ® (tagraxofusp-erzs) U.S. Indication: ELZONRIS (tagraxofusp-erzs) is a prescription medicine used to treat blastic plasmacytoid dendritic cell neoplasm (BPDCN) in adults and pediatric patients 2 years and older. Full prescribing information for the U.S. can be found at IMPORTANT SAFETY INFORMATION, ELZONRIS ® Boxed WARNING: CAPILLARY LEAK SYNDROME Capillary Leak Syndrome (CLS) which may be life-threatening or fatal, can occur in patients receiving ELZONRIS. Monitor for signs and symptoms of CLS and take actions as recommended. Warnings and Precautions Capillary Leak Syndrome Capillary leak syndrome (CLS), including life-threatening and fatal cases, has been reported among patients treated with ELZONRIS. In patients receiving ELZONRIS in clinical trials, the overall incidence of CLS was 53% (65/122), including Grade 1 or 2 in 43% (52/122) of patients, Grade 3 in 7% (8/122) of patients, Grade 4 in 1% (1/122) of patients, and four fatalities (3%). The median time to onset was 4 days (range - 1 to 46 days), and all but 5 patients experienced an event in Cycle 1. Before initiating therapy with ELZONRIS, ensure that the patient has adequate cardiac function and serum albumin is greater than or equal to 3.2 g/dL. During treatment with ELZONRIS, monitor serum albumin levels prior to the initiation of each dose of ELZONRIS and as indicated clinically thereafter, and assess patients for other signs or symptoms of CLS, including weight gain, new onset or worsening edema, including pulmonary edema, hypotension or hemodynamic instability. Hypersensitivity Reactions ELZONRIS can cause severe hypersensitivity reactions. In patients receiving ELZONRIS in clinical trials, hypersensitivity reactions were reported in 43% (53/122) of patients treated with ELZONRIS and were Grade ≥ 3 in 7% (9/122). Manifestations of hypersensitivity reported in ≥ 5% of patients include rash, pruritus, and stomatitis. Monitor patients for hypersensitivity reactions during treatment with ELZONRIS. Interrupt ELZONRIS infusion and provide supportive care as needed if a hypersensitivity reaction should occur. Hepatotoxicity Treatment with ELZONRIS was associated with elevations in liver enzymes. In patients receiving ELZONRIS in clinical trials, elevations in ALT occurred in 79% (96/122) and elevations in AST occurred in 76% (93/122). Grade 3 ALT elevations were reported in 26% (32/122) of patients. Grade 3 AST elevations were reported in 30% (36/122) and Grade 4 AST elevations were reported in 3% (4/122) of patients. Elevated liver enzymes occurred in the majority of patients in Cycle 1 and were reversible following dose interruption. Monitor alanine aminotransferase (ALT) and aspartate aminotransferase (AST) prior to each infusion with ELZONRIS. Withhold ELZONRIS temporarily if the transaminases rise to greater than 5 times the upper limit of normal and resume treatment upon normalization or when resolved. Adverse Reactions Most common adverse reactions (incidence ≥ 30%) are capillary leak syndrome, nausea, fatigue, pyrexia, peripheral edema, and weight increase. Most common laboratory abnormalities (incidence ≥ 50%) are decreases in albumin, platelets, hemoglobin, calcium, and sodium, and increases in glucose, ALT and AST. Please see full Prescribing Information , including Boxed WARNING. To report SUSPECTED ADVERSE REACTIONS, contact Stemline Therapeutics, Inc. at 1-877-332-7961 or contact the FDA at 1-800-FDA-1088 or . About NEXPOVIO ® (selinexor) NEXPOVIO ® has been approved in the following oncology indications by the European Commission: (i) in combination with dexamethasone for the treatment of multiple myeloma in adult patients who have received at least four prior therapies and whose disease is refractory to at least two proteasome inhibitors, two immunomodulatory agents and an anti-CD38 monoclonal antibody, and who have demonstrated disease progression on the last therapy; and (ii) in combination with bortezomib and dexamethasone for the treatment of adults with multiple myeloma who have received at least one prior therapy. The marketing authorization of NEXPOVIO is valid in the EU Member States as well as Iceland, Liechtenstein, Norway, and Northern Ireland. NEXPOVIO has been commercially available in Germany and Austria since Q4 2022. NEXPOVIO is a first-in-class, oral exportin 1 (XPO1) inhibitor. NEXPOVIO functions by selectively binding to and inhibiting the nuclear export protein exportin 1 (XPO1, also called CRM1). NEXPOVIO blocks the nuclear export of tumor suppressor, growth regulatory and anti-inflammatory proteins, leading to accumulation of these proteins in the nucleus and enhancing their anti-cancer activity in the cell. The forced nuclear retention of these proteins can counteract a multitude of the oncogenic pathways that, unchecked, allow cancer cells with severe DNA damage to continue to grow and divide in an unrestrained fashion. Please see NEXPOVIO® Summary of Product Characteristics (SmPC) and European Public Assessment Report at Please refer to local prescribing information where NEXPOVIO is approved for full information. In the U.S., Karyopharm Therapeutics markets selinexor as XPOVIO and the full prescribing information is available here . IMPORTANT SAFETY INFORMATION for NEXPOVIO Contraindications: Hypersensitivity to selinexor or to any of the excipients listed in the SmPC. Special warnings and precautions for use: Recommended concomitant treatments Patients should be advised to maintain adequate fluid and caloric intake throughout treatment. Intravenous hydration should be considered for patients at risk of dehydration. Prophylactic concomitant treatment with a 5-HT3 antagonist and/or other anti-nausea agents should be provided prior to and during treatment with NEXPOVIO ® . Haematology: Patients should have their complete blood counts (CBC) assessed at baseline, during treatment, and as clinically indicated. Monitor more frequently during the first two months of treatment. Thrombocytopenia: Thrombocytopenic events (thrombocytopenia and platelet count decreased) were frequently reported in adult patients receiving selinexor, which can be severe (Grade 3/4). Grade 3/4 thrombocytopenia can sometimes lead to clinically significant bleeding and in rare cases may lead to potentially fatal haemorrhage. Thrombocytopenia can be managed with dose interruptions, modifications, platelet transfusions, and/or other treatments as clinically indicated. Patients should be monitored for signs and symptoms of bleeding and evaluated promptly. Neutropenia: Severe neutropenia (Grade 3/4) has been reported with selinexor. In a few cases concurrent infections occurred in patients with Grade 3/4 neutropenia. Patients with neutropenia should be monitored for signs of infection and evaluated promptly. Gastrointestinal toxicity: Nausea, vomiting, diarrhoea, which sometimes can be severe and may require the use of anti-emetic and anti-diarrhoeal medicinal products. Prophylaxis with 5HT3 antagonists and/or other anti-nausea agents should be provided prior to and during treatment with selinexor. Fluids with electrolytes should be administered to prevent dehydration in patients at risk. Nausea/vomiting can be managed by dose interruptions, modifications, and/or initiation of other antiemetics medicinal products as clinically indicated. Diarrhoea can be managed with dose interruptions, modifications and/or administration of anti-diarrhoea medicinal products. Weight loss and anorexia: Patients should have their body weight, nutritional status and volume checked at baseline, during treatment, and as clinically indicated. Monitoring should be more frequent during the first two months of treatment. Patients experiencing new or worsening decreased appetite and weight may require dose modification, appetite stimulants, and nutritional consultations. Confusional state and dizziness: Patients should be instructed to avoid situations where dizziness or confusional state may be a problem and to not take other medicinal products that may cause dizziness or confusional state without adequate medical advice. Patients should be advised not to drive or operate heavy machinery until symptoms resolve. Hyponatraemia: Patients should have their sodium levels checked at baseline, during treatment, and as clinically indicated. Monitoring should be more frequent during the first two months of treatment. Hyponatraemia should be treated as per medical guidelines (intravenous sodium chloride solution and/or salt tablets), including dietary review. Cataract: Selinexor can cause new onset or exacerbation of cataract. Ophthalmologic evaluation may be performed as clinically indicated. Cataract should be treated as per medical guidelines, including surgery if warranted. Tumour lysis syndrome (TLS): TLS has been reported in patients receiving therapy with selinexor. Patients at a high risk for TLS should be monitored closely. Treat TLS promptly in accordance with institutional guidelines. Fertility, pregnancy and lactation : Women of childbearing potential should be advised to avoid becoming pregnant or abstain from sexual intercourse while being treated with selinexor and for at least 1 week following the last dose of selinexor. Women of childbearing potential/contraception in males and females: Women of childbearing potential and male adult patients of reproductive potential should be advised to use effective contraceptive measures or abstain from sexual intercourse while being treated with selinexor and for at least 1 week following the last dose of selinexor. Pregnancy: There are no data from the use of selinexor in pregnant women. Selinexor is not recommended during pregnancy and in women of childbearing potential not using contraception. If the patient becomes pregnant while taking selinexor, selinexor should be immediately discontinued, and the patient should be apprised of the potential hazard to the foetus. Breast-feeding: It is unknown whether selinexor or its metabolites are excreted in human milk. A risk to breast-fed children cannot be excluded. Breast-feeding should be discontinued during treatment with selinexor and for 1 week after the last dose. Undesirable effects Summary of the safety profile : The most frequent adverse reactions (≥30%) of selinexor in combination with bortezomib and dexamethasone were nausea, thrombocytopenia, fatigue, anaemia, decreased weight, diarrhea, and peripheral neuropathy. The most commonly reported serious adverse reactions (≥3%) were pneumonia, cataract, sepsis, diarrhoea, vomiting and anaemia. The most frequent adverse reactions (≥30%) of selinexor in combination with dexamethasone were nausea, thrombocytopenia, fatigue, anaemia, decreased appetite, decreased weight, diarrhoea, vomiting, hyponatraemia, neutropenia and leukopenia. The most commonly reported serious adverse reactions were pneumonia, sepsis thrombocytopenia, acute kidney injury, and anaemia. Description of selected adverse reactions: Infections: Infection was the most common non-haematological toxicity. In patients who received selinexor in combination with bortezomib and dexamethasone, upper respiratory tract infection and pneumonia were the most commonly reported infections in 21% and 15% of patients, respectively. In patients who received selinexor in combination with dexamethasone, upper respiratory tract infection and pneumonia were the most commonly reported infections (in 15% and 13% of patients, respectively) with 25% of reported infections being serious and fatal infections occurring in 3% of treated patients. Elderly population: Patients 75 years and older had a higher incidence of discontinuation due to an adverse reaction, higher incidence of serious adverse reactions, and higher incidence of fatal adverse reactions. Reporting of suspected adverse reactions : Reporting of suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the national reporting system listed in Appendix V. About The Menarini Group The Menarini Group is a leading international pharmaceutical and diagnostics company, with a turnover of $5.5 billion and over 17,000 employees. Menarini is focused on therapeutic areas with high unmet needs with products for cardiology, oncology, pneumology, gastroenterology, infectious diseases, diabetology, inflammation, and analgesia. With 18 production sites and 9 Research and Development centers, Menarini’s products are available in 140 countries worldwide. For further information, please visit . About Stemline Therapeutics Inc. Stemline Therapeutics, Inc. (“Stemline”), a wholly-owned subsidiary of the Menarini Group, is a commercial-stage biopharmaceutical company focused on bringing transformational oncology treatments to patients. Stemline commercializes elacestrant, an oral endocrine therapy indicated for the treatment of postmenopausal women or adult men with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative, ESR1 -mutated advanced or metastatic breast cancer with disease progression following at least one line of endocrine therapy, in the U.S., Europe, and other global regions. Stemline also commercializes tagraxofusp-erzs, a novel targeted therapy directed to CD123, for patients with blastic plasmacytoid dendritic cell neoplasm (BPDCN), an aggressive hematologic cancer, in the United States, Europe, and other global regions. In addition, Stemline commercializes selinexor, an XPO1 inhibitor for multiple myeloma, in Europe. The company is also conducting multiple label-expansion studies with elacestrant and tagraxofusp in breast and hematologic cancer indications, respectively, and has an extensive clinical pipeline of additional drug candidates in various stages of development for a host of solid and hematologic cancers. Media Contacts The Menarini Group Valeria Speroni Cardi Email: pressoffice@menarini.com Stemline Therapeutics, Inc. Cheya Pope Email: media@menarinistemline.com