A Phase 1/2 interventional study of Samuraciclib and Elacestrant Dihydrochloride in Metastatic Breast Cancer, Locally Advanced Breast Cancer and Breast Cancer, sponsored by Carrick Therapeutics Limited. Completed at 23 sites in 4 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-03-23.
Sponsored by Carrick Therapeutics Limited · Phase 1/2, Interventional, and Treatment
This is an international, multisite, open-label, Phase 1b/2 study, to confirm safety and efficacy of samuraciclib in combination with elacestrant in adult participants with metastatic or locally advanced Hormone Receptor (HR) positive and Human Epidermal Growth Factor Receptor (HER)2-negative breast cancer.
This is a multiple cohort study, an initial dose escalation phase is designed to confirm the safe dose of samuraciclib in combination with elacestrant. A Safety Review Committee (SRC) will monitor the safety, tolerability, and PK data during this phase. Once ascertained, an expansion cohort will be opened to explore the efficacy of samuraciclib in combination with elacestrant.
12,544 studies on the registry are indexed under Breast Neoplasms; 2,892 are open to participants now.
This study's enrollment of 49 is below the median of 72 across 9,303 interventional studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →Carrick Therapeutics Limited is the lead sponsor of 4 studies on the registry; 1 is open to participants now.
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Exclusion Criteria:
Up to 6 evaluable participants will receive samuraciclib 240 mg in combination with elacestrant 300 mg in cycles of 28 days (Cycle 1 to 6), 56 days (Cycle 7 to 9) and up to 84 days (Cycles 10 onwards).
Drug: Samuraciclib · Drug: Elacestrant Dihydrochloride
Up to 6 evaluable participants will receive samuraciclib in combination with elacestrant at the SRC recommended dose (anticipated 360mg samuraciclib, 300 mg elacestrant) in cycles of 28 days (Cycle 1 to 6), 56 days (Cycle 7 to 9) and up to 84 days (Cycles 10 onward).
Drug: Samuraciclib · Drug: Elacestrant Dihydrochloride
Up to 6 evaluable participants will receive samuraciclib in combination with elacestrant at the SRC recommended dose (anticipated 360mg samuraciclib, 400 mg elacestrant) in cycles of 28 days (Cycle 1 to 6), 56 days (Cycle 7 to 9) and up to 84 days (Cycles 10 onward).
Drug: Samuraciclib · Drug: Elacestrant Dihydrochloride
Up to 30 evaluable participants will receive samuraciclib in combination with elacestrant at the SRC recommended dose (anticipated 360mg samuraciclib, 400 mg elacestrant) in cycles of 28 days (Cycle 1 to 6), 56 days (Cycle 7 to 9) and up to 84 days (Cycles 10 onward).
Drug: Samuraciclib · Drug: Elacestrant Dihydrochloride
Samuraciclib capsules by mouth once a day
Elacestrant tablets by mouth once a day
Also known as: ORSERDU
Phase 1b (Dose-finding)
Identification of Samuraciclib + Elacestrant combination, Phase 2, expansion dose level. Incidence and severity of adverse events as graded by the National Cancer Institute Common Terminology Criteria for Adverse events (NCI-CTCAE) v5.0. Safety will be assessed by monitoring treatment - emerged severe and dose limiting adverse events and clinically relevant changes in vital signs and clinical laboratory results
Time frame: From the date of first dose of any study intervention (Day 1 Cycle 1) and through 28 days after the last dose of any study intervention
Phase 2 (Expansion)
Progression Free Survival (PFS) is defined as the time from the date of first dose of IMP (Cycle 1 Day 1) to the date of the first documentation of objective progressive disease (PD) or death due to any cause, whichever occurs first.
Time frame: From the date of first dose of any study intervention (Cycle 1 Day 1) until the first documentation of disease progression, death, withdrawal of consent, or start of new anticancer therapy (assessed up to week 48)
Treatment-Emergent Adverse Events and Laboratory Abnormalities (Safety and Tolerability)
Type, incidence, severity (as graded by CTCAE v5.0), seriousness and relationship to study medications of AEs and any laboratory abnormalities. Safety will be assessed by monitoring adverse events and clinically relevant changes in vital signs and clinical laboratory results.
Time frame: From the date of first dose of any study intervention through 28 days after the last dose of any study intervention
Clinical Benefit Response (CBR)
CBR is defined as the overall complete response (CR), partial response (PR), or stable disease (SD) ≥ 24 weeks according to RECIST version 1.1 recorded from enrolment until disease progression, or death due to any cause.
Time frame: From the date of first dose of any study intervention (Cycle 1 Day 1) to ≥ 24 weeks or until disease progression or death to any cause (assessed up to week 24)
Overall response rate (ORR)
ORR is defined as the proportion of participants with a reduction in tumor burden with CR or PR according to RECIST version 1.1. ORR will be estimated for participants who received at least 1 dose of IMP, had measurable disease at baseline and had a postbaseline tumor assessment.
Time frame: the date of first dose of study intervention (Cycle 1 Day 1) until the first documentation of disease progression, death, withdrawal of consent, or start of new anticancer therapy (assessed up to week 48)
Duration of Response (DOR)
DOR is defined as the time from the date of first documentation of objective tumor response (CR or PR) to the earliest documented disease progression per RECIST version 1.1
Time frame: From the date of first dose of study intervention (Cycle 1 Day 1) until the first documentation of disease progression, death, withdrawal of consent, or start of new anticancer therapy (assessed up to week 48)
Best percent change in tumor size.
Best percent change in tumor size is defined as the percentage change in the sum of the longest diameters of target lesions
Time frame: From the date of first dose of study intervention (Cycle 1 Day 1) until the first documentation of disease progression, death, withdrawal of consent, or start of new anticancer therapy (assessed up to week 48)
Samuraciclib plasma exposure: Cmax
Plasma concentration for Samuraciclib
Time frame: Day 1 of Cycles 1 and Cycle 2 (each cycle is 28 days)
Elacestrant exposure: Cmax
Plasma concentrations for Elacestrant
Time frame: Day 1 of Cycles 1 and Cycle 2 (each cycle is 28 days)
Samuraciclib plasma exposure: Ctrough
Time frame: Cycle 1 Day 2 and 15; Day 2 of Cycle 2; Day 1 of Cycles 3-6 and end of treatment within 28 days of last dose of IMP and prior to the initiation of a new anticancer therapy (each cycle is 28 days)]
Elacestrant exposure: Ctrough
Time frame: Cycle 1 Day 2 and Day 15; Cycle 2 Day 2 of Cycle 2 and Day 1 of Cycles 3-6 and at end of treatment within 28 days of the last dose of IMP and prior to the initiation of a new anticancer therapy (each cycle is 28 days)
Genotyping for ESR1 and TP53 mutations
Genotyping for ESR1 and TP53 mutations to evaluate correlations between ESR1 and TP53 mutations and efficacy/safety findings
Time frame: Screening
This study is completed, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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Carrick Therapeutics Limited