Clinical trial • Phase III • Oncology

Palazestrant / OP-1250 for Estrogen receptor–positive (ER+), HER2-negative advanced/metastatic breast cancer

Phase III trial of Palazestrant / OP-1250 for Estrogen receptor–positive (ER+), HER2-negative advanced/metastatic breast cancer.

Overview

Trial Therapeutic Area
Oncology
Trial Disease
Estrogen receptor–positive (ER+), HER2-negative advanced/metastatic breast cancer
Trial Stage
Phase III
Drug Modality
Small molecule|Peptide/protein/enzyme

Key dates

Initial CTIS Submission Date
20-11-2023
First CTIS Authorization Date
25-03-2024

Trial design

Randomised, open-label, investigator choice standard-of-care endocrine therapy (fulvestrant or aromatase inhibitors: anastrozole, letrozole, exemestane) used per local prescribing information (doses/schedules per local ma; specific trial text does not list comparator dosing in the ctis data).-controlled, adaptive Phase III trial in Belgium, Bulgaria, Netherlands and others.

Randomised
Yes
Open Label
Yes
Comparator
Investigator Choice standard-of-care endocrine therapy (Fulvestrant OR Aromatase Inhibitors: Anastrozole, Letrozole, Exemestane) used per local prescribing information (doses/schedules per local MA; specific trial text does not list comparator dosing in the CTIS data).
Adaptive
True, dose selection adaptive element: Part 1 randomizes to palazestrant 90 mg, palazestrant 120 mg, and SOC; dose selection assessment when ~40 participants per palazestrant arm have completed 4 cycles (16 weeks); enrollment pauses until selected dose is recommended and Part 2 opens with the selected dose.
Biomarker Stratified
True, biomarker: ESR1-activating mutation(s) detected in ctDNA; strata: ESR1-mut vs ESR1-mut-nd
Single Multiple Or Escalation Dose Combined
Yes
Target Sample Size
510

Stratification factors

  • ESR1 activating mutation(s) detected in ctDNA (ESR1-mut vs ESR1-mut-nd)
  • Prior lines of endocrine therapy for advanced disease (1 line vs 2 lines)
  • Presence of visceral metastases (yes vs no)

Eligibility

Recruits 510 Vulnerable population selected. Informed consent documents are provided (Main ICF and specific Pregnant Participant / Pregnant Partner ICFs). Adult participants provide consent; specific ICFs for pregnant participants/partners are included in the documentation..

Vulnerable Population
Vulnerable population selected. Informed consent documents are provided (Main ICF and specific Pregnant Participant / Pregnant Partner ICFs). Adult participants provide consent; specific ICFs for pregnant participants/partners are included in the documentation.

Inclusion criteria

  • {"criterion_text":"- Adult female or male participants.\n- ER+, HER2- locally advanced or metastatic breast cancer that is not amenable to curative therapy.\n- Evaluable disease (measurable disease or bone-only disease).\n- Previously received a CDK4/6 inhibitor in combination with an endocrine therapy in the advanced setting. One additional line of ET as a monotherapy will be allowed.\n- Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.\n- Adequate hematologic, hepatic, and renal functions.\n- Female participants can be pre-, peri- or postmenopausal.\n- Male and pre- or peri-menopausal female participants must be willing to take a GnRH (LHRH) agonist."}

Exclusion criteria

  • {"criterion_text":"- Symptomatic visceral disease, imminent organ failure, or any disease burden that makes the participant ineligible for endocrine therapy.\n- Have received prior chemotherapy (including an antibody-drug conjugate) in the advanced/metastatic setting.\n- Any contraindications to the selected standard of care endocrine therapy in the local prescribing information.\n- Symptomatic central nervous system metastases, carcinomatous meningitis, leptomeningeal disease, or a spinal cord compression that require immediate treatment\n- Clinically significant comorbidities such as significant cardiac or cerebrovascular disease, or gastrointestinal disorders that could aff+F120ect absorption of study treatment, and others"}

Endpoints

Primary endpoints

  • {"endpoint_text":"- Safety and tolerability, assessed by AEs, SAEs, dose modifications, clinical laboratory parameters (ie, hematology, chemistry, and coagulation), ECGs, and vital signs measurements\n- BIRC-assessed PFS","definition_or_measurement_approach":"Safety and tolerability: assessed by adverse events (AEs), serious adverse events (SAEs), dose modifications, clinical laboratory parameters (hematology, chemistry, coagulation), ECGs, and vital signs. BIRC-assessed PFS: progression-free survival assessed by a blinded independent review committee (BIRC)."}

Secondary endpoints

  • {"endpoint_text":"- 1. Local investigator-assessed ORR, DoR, DCR, CBR, and PFS\n- 2. Plasma levels of OP-1250 at predefined intervals to establish PK parameters (including: Cmax, Cmin, Tmax, AUC, and OP-1250 trough concentration at steady state)\n- 3. Overall Survival\n- 4. BIRC-assessed PFS\n- 5. Overall survival","definition_or_measurement_approach":"Local investigator assessments of tumor response metrics (ORR, DoR, DCR, CBR, PFS). PK parameters determined from plasma OP-1250 levels (Cmax, Cmin, Tmax, AUC, trough concentration at steady state). Overall survival measured as time from randomization to death. BIRC-assessed PFS as adjudicated by blinded independent review committee."}
  • {"endpoint_text":"- 6. Local investigator-assessed PFS\n- 7. BIRC-assessed ORR\n- 8. BIRC-assessed DoR\n- 9. BIRC-assessed CBR\n- 10. Local investigator-assessed ORR\n- 11. Local investigator-assessed DoR\n- 12. Local investigator-assessed CBR\n- 13. Safety and tolerability, assessed by AEs, SAEs, dose modifications, clinical laboratory parameters (ie, hematology, chemistry, and coagulation), ECGs, performance status, and vital sign measurements","definition_or_measurement_approach":"Investigator- and BIRC-assessed tumor response and survival endpoints as above. Safety and tolerability endpoints assessed by AEs, SAEs, dose changes, labs, ECGs, performance status and vital signs."}
  • {"endpoint_text":"- 14. Plasma levels of palazestrant at predefined intervals to establish PK parameters (including: Cmax, Cmin, Tmax, AUC, t1/2, and palazestrant trough concentration at steady state)\n- 15. PRO endpoints, assessed using the EORTC-QLQ-C30 and EQ-5D-5L questionnaires","definition_or_measurement_approach":"PK endpoints: plasma palazestrant concentrations at predefined intervals to determine Cmax, Cmin, Tmax, AUC, t1/2, and trough concentration at steady state. PROs assessed using EORTC-QLQ-C30 and EQ-5D-5L instruments."}

Recruitment

Registry Or Advocacy Recruitment
True, named organisations present in trial documentation/sites: Althaia Xarxa Assistencial Universitaria De Manresa Fundacio Privada (Spain); Centre Jean Perrin (France) (both listed as Patient organisation/association in trial sites/documents).
Planned Sample Size
510
Recruitment Window Months
44
Consent Approach
Informed consent obtained from adult participants via a Main ICF. Country- and language-specific ICFs are provided (document titles show ICFs in English, Dutch, French, German, Hungarian, Italian, Portuguese, Spanish, Bulgarian, Czech, Polish, Romanian, Russian/Ukrainian, and others). Specific Pregnant Participant and Pregnant Partner ICFs are included where applicable. No paediatric assent processes are indicated (adults only).

Methods

  • GP-letter documents (K2_GP-letter) are included in country-specific materials (indicates use of general practitioner engagement letters to support recruitment).
  • Country/site-specific 'Recruitment arrangements' (K1) documents are provided for multiple countries (titles available for BE, BG, NL, ES, HU, IT, DE, FR, PT, RO, etc.), indicating site-level and country-specific recruitment plans (document titles only).
  • Patient travel and reimbursement support is provided (role listed: 'Patient Travel and Reimbursement management' by Scout Clinical).

Geography

Total Number Of Sites
104
Total Number Of Participants
382

Belgium

Earliest CTIS Part Ii Submission Date
13-03-2024
Latest Decision Or Authorization Date
10-03-2026
Processing Time Days
727
Number Of Sites
4
Number Of Participants
25

Bulgaria

Earliest CTIS Part Ii Submission Date
01-03-2024
Latest Decision Or Authorization Date
16-03-2026
Processing Time Days
745
Number Of Sites
2
Number Of Participants
9

Netherlands

Earliest CTIS Part Ii Submission Date
27-02-2024
Latest Decision Or Authorization Date
06-03-2026
Processing Time Days
738
Number Of Sites
2
Number Of Participants
10

Spain

Earliest CTIS Part Ii Submission Date
19-03-2024
Latest Decision Or Authorization Date
09-03-2026
Processing Time Days
720
Number Of Sites
20
Number Of Participants
60

Hungary

Earliest CTIS Part Ii Submission Date
11-03-2024
Latest Decision Or Authorization Date
09-03-2026
Processing Time Days
728
Number Of Sites
3
Number Of Participants
18

Austria

Earliest CTIS Part Ii Submission Date
29-02-2024
Latest Decision Or Authorization Date
09-03-2026
Processing Time Days
740
Number Of Sites
2
Number Of Participants
7

Portugal

Earliest CTIS Part Ii Submission Date
04-03-2024
Latest Decision Or Authorization Date
09-03-2026
Processing Time Days
735
Number Of Sites
5
Number Of Participants
25

Italy

Earliest CTIS Part Ii Submission Date
13-03-2024
Latest Decision Or Authorization Date
10-03-2026
Processing Time Days
727
Number Of Sites
17
Number Of Participants
65

Germany

Earliest CTIS Part Ii Submission Date
11-03-2024
Latest Decision Or Authorization Date
12-03-2026
Processing Time Days
731
Number Of Sites
5
Number Of Participants
24

France

Earliest CTIS Part Ii Submission Date
25-01-2024
Latest Decision Or Authorization Date
10-03-2026
Processing Time Days
774
Number Of Sites
13
Number Of Participants
36

Czechia

Earliest CTIS Part Ii Submission Date
19-03-2024
Latest Decision Or Authorization Date
06-03-2026
Processing Time Days
717
Number Of Sites
4
Number Of Participants
37

Poland

Earliest CTIS Part Ii Submission Date
13-03-2024
Latest Decision Or Authorization Date
08-03-2026
Processing Time Days
725
Number Of Sites
13
Number Of Participants
36

Romania

Earliest CTIS Part Ii Submission Date
04-12-2023
Latest Decision Or Authorization Date
16-03-2026
Processing Time Days
832
Number Of Sites
14
Number Of Participants
30

Sponsor

Primary sponsor

Full Name
Olema Pharmaceuticals Inc.
Organisation Type
Pharmaceutical company
Country Of Registered Address
United States

Contract research organisations

Name
PPD Development LP
Responsibilities
Medical Writing and multiple central trial functions (codes listed in CTIS)
Name
4g Clinical LLC
Name
Almac Clinical Services Limited
Responsibilities
Supply of OP-1250; centrally provided SoC & GnRH/LHRH
Name
Medidata Solutions Inc.
Responsibilities
ePRO

Third parties

  • {"country":"United States","full_name":"4g Clinical LLC","duties_or_roles":"","organisation_type":"Non-Pharmaceutical company"}
  • {"country":"United States","full_name":"Guardant Health Inc.","duties_or_roles":"ESR-1 Mutation Testing","organisation_type":"Laboratory/Research/Testing facility"}
  • {"country":"United States","full_name":"Medidata Solutions Inc.","duties_or_roles":"ePRO","organisation_type":"Non-Pharmaceutical company"}
  • {"country":"United Kingdom","full_name":"Almac Clinical Services Limited","duties_or_roles":"OP-1250; centrally provided SoC & GnRH/LHRH","organisation_type":"Pharmaceutical company"}
  • {"country":"United States","full_name":"Eresearchtechnology Inc.","duties_or_roles":"ECG","organisation_type":"Pharmaceutical company"}
  • {"country":"Ireland","full_name":"Clinical Technology Centre (Ireland) Limited","duties_or_roles":"centrally provided SoC & GnRH/LHRH","organisation_type":"Pharmaceutical company"}
  • {"country":"United States","full_name":"Bioclinica Inc.","duties_or_roles":"Imaging","organisation_type":"Laboratory/Research/Testing facility"}
  • {"country":"United States","full_name":"Scout Clinical","duties_or_roles":"Patient Travel and Reimbursement management","organisation_type":"Hospital/Clinic/Other health care facility"}
  • {"country":"United States","full_name":"PPD Development LP","duties_or_roles":"Medical Writing and other central services (multiple sponsor duties listed)","organisation_type":"Pharmaceutical company"}
  • {"country":"United States","full_name":"Labcorp Early Development Laboratories Inc.","duties_or_roles":"PK and tumor tissue sample","organisation_type":"Pharmaceutical company"}

Investigational products

Investigational Product Name
Palazestrant (OP-1250)
Active Substance
Palazestrant / OP-1250
Modality
Small molecule
Routes Of Administration
ORAL
Route
Oral
Authorisation Status
1
Starting Dose
90 mg and 120 mg (dose selection evaluated in Part 1)
Dose Levels
90 mg; 120 mg
Maximum Dose
120 mg
Dose Escalation Increase
Initial: 90 mg; Following: 120 mg
Investigational Product Name
Fulvestrant
Active Substance
Fulvestrant
Modality
Small molecule
Routes Of Administration
INTRAMUSCULAR INJECTION
Route
Intramuscular injection
Authorisation Status
2
Maximum Dose
500 mg (maxDailyDoseAmount field)
Investigational Product Name
Exemestane
Active Substance
Exemestane
Modality
Small molecule
Routes Of Administration
ORAL
Route
Oral
Authorisation Status
2
Maximum Dose
25 mg
Investigational Product Name
Goserelin acetate
Active Substance
Goserelin acetate
Modality
Peptide/protein/enzyme
Routes Of Administration
SUBCUTANEOUS INJECTION
Route
Subcutaneous injection
Authorisation Status
2
Maximum Dose
3.6 mg
Investigational Product Name
Letrozole
Active Substance
Letrozole
Modality
Small molecule
Routes Of Administration
ORAL
Route
Oral
Authorisation Status
2
Maximum Dose
2.5 mg
Investigational Product Name
Anastrozole
Active Substance
Anastrozole
Modality
Small molecule
Routes Of Administration
ORAL
Route
Oral
Authorisation Status
2
Maximum Dose
1 mg

Related trials

Other published trials that may interest you.