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Study Assessing the Efficacy and Safety of Alpelisib Plus Fulvestrant in Men and Postmenopausal Women With Advanced Breast Cancer Which Progressed on or After Aromatase Inhibitor Treatment.

A Phase III Randomized Double-blind, Placebo Controlled Study of Alpelisib in Combination With Fulvestrant for Men and Postmenopausal Women With Hormone Receptor Positive, HER2-negative Advanced Breast Cancer Which Progressed on or After Aromatase Inhibitor Treatment

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02437318
Acronym
SOLAR-1
Enrollment
572
Registered
2015-05-07
Start date
2015-07-23
Completion date
2023-06-09
Last updated
2025-02-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Breast Cancer

Keywords

BYL719, HR+, HER2-negative, advanced breast cancer, alpelisib, fulvestrant, PI3K, Phase III, ER+, PgR+, men, postmenopausal, aromatase inhibitor, neoplasms

Brief summary

To determine whether treatment with alpelisib plus fulvestrant prolonged progression-free survival (PFS) compared to fulvestrant and placebo in men and postmenopausal women with hormone receptor positive (HR+), human epidermal growth factor receptor-2 (HER2)-negative advanced breast cancer, who received prior treatment with an aromatase Inhibitor (AI) either as (neo)adjuvant or for advanced disease.

Detailed description

This was a randomized, double-blind, placebo-controlled, international multicenter Phase III study that evaluated the efficacy and safety of treatment with alpelisib plus fulvestrant versus placebo plus fulvestrant in men and postmenopausal women with HR-positive, HER2-negative advanced breast cancer which had progressed on or after AI treatment. Subjects were allocated to either the PIK3CA mutant or PIK3CA non-mutant cohort, based on central testing of hotspot-mutations in tumor tissue. Subjects with unknown results were not eligible. Within each cohort, subjects were randomized in a 1:1 ratio to receive either alpelisib 300 mg orally once daily (q.d.), in combination with fulvestrant 500 mg intramuscular (i.m.) on Days 1 and 15 of Cycle 1 and Day 1 of a 28-day cycle thereafter, or placebo daily in combination with fulvestrant 500 mg following the same treatment regimen. Subjects were treated until disease progression, unacceptable toxicity, death, or discontinuation from the study treatment for any other reason. All subjects who discontinued study treatment were followed for safety, until 30 days after last study treatment administration, except in the case of death, loss to follow-up, or withdrawal of consent. Subjects who discontinued study treatment for reasons other than disease progression or withdrawal of consent, were followed until disease progression, death, withdrawal of consent, loss to follow-up, or subject/guardian decision (post-treatment efficacy follow-up). Finally, all subjects were followed for survival after discontinuation of study treatment and tumor evaluations until the subject's death, loss to follow-up, or withdrawal of consent for survival follow-up (post-treatment survival follow-up)

Interventions

DRUGFulvestrant

500 mg of fulvestrant administered via intramuscular injection on Day 1 and Day 15 of Cycle 1, and then Day 1 of each subsequent 28-day cycle

DRUGAlpelisib

300 mg of alpelisib tablets for oral use administered once daily

DRUGPlacebo

300 mg of placebo tablets for oral use administered once daily

Sponsors

Novartis Pharmaceuticals
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Investigator)

Eligibility

Sex/Gender
ALL
Age
18 Years to 100 Years
Healthy volunteers
No

Inclusion criteria

* If female, the patient was postmenopausal. * The patient had identified PIK3CA status. * Patients could be: * Relapsed with documented evidence of progression while on (neo)adjuvant endocrine therapy or within 12 months from completion of (neo)adjuvant endocrine therapy with no treatment for metastatic disease. * Relapsed with documented evidence of progression more than 12 months from completion of (neo)adjuvant endocrine therapy and then subsequently progressed with documented evidence of progression while on or after only one line of endocrine therapy for metastatic disease. * Newly diagnosed with advanced breast cancer, then relapsed with documented evidence of progression while on or after only one line of endocrine therapy. * The patient had recurrence or progression of the disease during or after AI therapy (i.e., letrozole, anastrozole, exemestane). * The patient had a histologically and/or cytologically confirmed diagnosis of estrogen-receptor positive breast cancer by a local laboratory and had HER2 negative breast cancer. * The patient had either measurable disease per RECIST 1.1 criteria or at least one predominantly lytic bone lesion present. * The patient had adequate bone marrow function.

Exclusion criteria

* The patient had symptomatic visceral disease or any disease burden that made the patient ineligible for endocrine therapy per the investigator's best judgment. * The patient had received prior treatment with chemotherapy (except for neoadjuvant/adjuvant chemotherapy), fulvestrant, any PI3K, mTOR, or AKT inhibitor (pre-treatment with CDK4/6 inhibitors was allowed). * The patient had inflammatory breast cancer at screening. * Patients had Child pugh score B or C. * Patients had an established diagnosis of diabetes mellitus type I or uncontrolled type II. * The patient had Eastern Cooperative Oncology Group (ECOG) performance status 2 or more. * The patient had CNS involvement unless he/she was at least 4 weeks from prior therapy completion to starting the study treatment and had a stable CNS tumor at the time of screening and was not receiving steroids and/or enzyme-inducing antiepileptic medications for brain metastases. * The patient had participated in a prior investigational study within 30 days prior to enrollment or within 5 half-lives of the investigational product, whichever was longer. * The patient had a history of acute pancreatitis within 1 year of screening or a past medical history of chronic pancreatitis. * The patient relapsed with documented evidence of progression more than 12 months from completion of (neo)adjuvant endocrine therapy with no treatment for metastatic disease.

Design outcomes

Primary

MeasureTime frameDescription
Progression-free Survival (PFS) Per Investigator Assessment in the PIK3CA Mutant CohortOnce approximately 243 PFS events in the PIK3CA mutant cohort had been observed, up to 33.3 monthsPFS was defined as the time from the date of randomization to the date of the first documented progression or death due to any cause. PFS was assessed via a local radiology assessment according to RECIST 1.1. If a patient did not have an event, PFS was censored at the date of last adequate tumor assessment. The PFS distribution was estimated using Kaplan-Meier methodology. Progression was defined as at least a 20% increase in the sum of diameter of all measured target lesions, taking as reference the smallest sum of diameter of all target lesions recorded at or after baseline. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm.

Secondary

MeasureTime frameDescription
Overall Survival (OS) in the PIK3CA Mutant CohortOnce approximately 178 deaths in the PIK3CA mutant cohort had been observed, up to 55.7 monthsOS was defined as the time from date of randomization to date of death due to any cause. If a patient was not known to have died, survival was censored at the date of last known date patient alive. The OS distribution was estimated using Kaplan-Meier methodology.
PFS Per Investigator Assessment in the PIK3CA Non-mutant CohortUp to 56.4 monthsPFS was defined as the time from the date of randomization to the date of the first documented progression or death due to any cause. PFS was assessed via a local radiology assessment according to RECIST 1.1. If a patient did not have an event, PFS was censored at the date of last adequate tumor assessment. The PFS distribution was estimated using Kaplan-Meier methodology. Progression was defined as at least a 20% increase in the sum of diameter of all measured target lesions, taking as reference the smallest sum of diameter of all target lesions recorded at or after baseline. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm.
OS in the PIK3CA Non-mutant CohortUp to 56.4 monthsOS was defined as the time from date of randomization to date of death due to any cause. If a patient was not known to have died, survival was censored at the date of last known date patient alive. The OS distribution was estimated using Kaplan-Meier methodology.
Overall Response Rate (ORR) Per Investigator AssessmentUp to 56.4 monthsORR was defined as the percentage of patients with best overall response of complete response (CR) or partial response (PR) based on local investigator's assessment according to RECIST 1.1. CR: Disappearance of all non-nodal target and non-target lesions. In addition, any pathological lymph nodes assigned as target and non-target lesions must have a reduction in short axis to \< 10 mm. PR: At least a 30% decrease in the sum of diameter of all target lesions, taking as reference the baseline sum of diameters.
Clinical Benefit Rate (CBR) Per Investigator AssessmentUp to 56.4 monthsClinical benefit rate was defined as the percentage of patients with a best overall response of CR or PR or stable disease (SD) or Non-CR/Non-PD lasting more than 24 weeks based on local investigator assessment according to RECIST 1.1. CR: Disappearance of all non-nodal target and non-target lesions. In addition, any pathological lymph nodes assigned as target and non-target lesions must have a reduction in short axis to \< 10 mm. PR: At least a 30% decrease in the sum of diameter of all target lesions, taking as reference the baseline sum of diameters. SD: Neither sufficient shrinkage to qualify for PR or CR nor an increase in lesions which would qualify for progressive disease.
Time to 10% Deterioration in the Global Health Status (GHS) /Quality of Life (QOL) Scale Score of the European Organization for Research and Treatment of Cancer's Core Quality of Life Questionnaire (EORTC QLQ-C30)From baseline up to 55.7 monthsThe EORTC QLQ-C30 is a questionnaire that includes 5 functional scales, 3 symptom scales, 1 GHS/QoL scale, and 6 single items. GHS/QoL scale score ranges between 0 and 100. A high score for GHS/QoL represents better functioning or QoL.The time to definitive 10% deterioration was defined as the time from the date of randomization to the date of event, which was defined as at least 10% relative to baseline worsening of the GHS/QoL score (without further improvement above the threshold) or death due to any cause. The Kaplan-Meier method was used to estimate the distribution. If a patient had not had an event, time to deterioration was censored at the date of the last adequate QoL evaluation.
Change From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Baseline, every 8 weeks after randomization during the first 18 months and thereafter every 12 weeks, up to 120 weeks.The EORTC QLQ-C30 is a questionnaire that includes 5 functional scales, 3 symptom scales, 1 GHS/QoL scale, and 6 single items. GHS/QoL scale score ranges between 0 and 100. A high score for GHS/QoL represents better functioning or QoL.The change from baseline in the GHS/QoL score was assessed. A positive change from baseline indicated improvement. For each cohort, this analysis only included assessments up to the time point where there were at least 10 patients on each of the 2 treatment groups.
Trough Plasma Concentration of AlpelisibDay 8 and Day 15 of Cycle 1, then Day 1 of Cycles 2, 4, 6 and 8. Cycle = 28 daysPre-dose plasma concentrations of alpelisib were assessed. Only participants randomized to the alpelisib + fulvestrant arm were included in this analysis.
Trough Plasma Concentration of FulvestrantDay 15 of Cycle 1, then Day 1 of Cycles 2, 4, 6 and 8. Cycle = 28 daysPre-dose plasma concentrations of fulvestrant were assessed.
PFS Per Investigator Criteria in Subjects With PIK3CA Mutation Status Measured in ctDNA at BaselineFrom baseline up to 56.4 monthsPFS was defined as the time from the date of randomization to the date of the first documented progression or death due to any cause. PFS was assessed via a local radiology assessment according to RECIST 1.1. If a patient did not have an event, PFS was censored at the date of last adequate tumor assessment. The PFS distribution was estimated using Kaplan-Meier methodology. Subjects were analyzed according to the PIK3CA mutation status (mutant or non-mutant) as identified using plasma ctDNA. Progression was defined as at least a 20% increase in the sum of diameter of all measured target lesions, taking as reference the smallest sum of diameter of all target lesions recorded at or after baseline. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm.
Time to Definitive Deterioration of Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) Score From BaselineFrom baseline up to 56.4 monthsECOG PS categorized patients based on their ability to perform daily activities and self-care, with scores ranging from 0 to 5. A score of 0 indicated no restrictions in activity, while higher scores indicated increasing limitations. Time to definitive deterioration of ECOG PS by one score was defined as the time from the date of randomization to the date of the event, defined as experiencing at least one score lower than the baseline. A deterioration was considered definitive if no improvements in the ECOG PS were observed at a subsequent time. The Kaplan-Meier method was used to estimate the distribution. Patients receiving any further therapy prior to definitive worsening were censored at their date of last assessment prior to start of therapy. Patients that had not worsened at the data cutoff point were censored at the date of last assessment.

Other

MeasureTime frameDescription
Updated PFS Per Investigator Assessment in the PIK3CA Mutant Cohort (Longer Follow-up)Up to 55.7 monthsPFS was defined as the time from the date of randomization to the date of the first documented progression or death due to any cause. PFS was assessed via a local radiology assessment according to RECIST 1.1. If a patient did not have an event, PFS was censored at the date of last adequate tumor assessment. The PFS distribution was estimated using Kaplan-Meier methodology. This analysis was conducted at the time of the final OS analysis (when approximately 178 deaths in the PIK3CA mutant cohort had been achieved) and includes a longer follow-up time. Progression was defined as at least a 20% increase in the sum of diameter of all measured target lesions, taking as reference the smallest sum of diameter of all target lesions recorded at or after baseline. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm.

Countries

Argentina, Australia, Austria, Belgium, Brazil, Bulgaria, Canada, Chile, Czechia, France, Germany, Greece, Hong Kong, Hungary, India, Israel, Italy, Japan, Lebanon, Mexico, Netherlands, Peru, Romania, Russia, South Korea, Spain, Sweden, Taiwan, Thailand, United Kingdom, United States

Participant flow

Recruitment details

Participants were enrolled in 198 centers across 31 countries

Pre-assignment details

One subject in the PIK3CA mutant cohort, who was randomized to the placebo + fulvestrant arm, did not receive study treatment due to a protocol deviation.

Participants by arm

ArmCount
Alpelisib + Fulvestrant
Subjects treated with alpelisib (300 mg; oral; once daily) in combination with fulvestrant (500 mg; intramuscular injection on Day 1 and Day 15 of Cycle 1, and then Day 1 of each subsequent 28-day cycle)
284
Placebo + Fulvestrant
Subjects treated with placebo (300 mg; oral; once daily) in combination with fulvestrant (500 mg; intramuscular injection on Day 1 and Day 15 of Cycle 1, and then Day 1 of each subsequent 28-day cycle)
288
Total572

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyAdverse Event144
Overall StudyDeath44
Overall StudyPhysician Decision2922
Overall StudyProgressive disease207240
Overall StudyProtocol deviation57
Overall StudySponsor decision10
Overall StudySubject/guardian decision2411

Baseline characteristics

CharacteristicAlpelisib + FulvestrantPlacebo + FulvestrantTotal
Age, Continuous62.6 Years
STANDARD_DEVIATION 9.74
63.3 Years
STANDARD_DEVIATION 10.26
63.0 Years
STANDARD_DEVIATION 10
Race/Ethnicity, Customized
American Indian or Alaska
1 Participants4 Participants5 Participants
Race/Ethnicity, Customized
Asian
59 Participants66 Participants125 Participants
Race/Ethnicity, Customized
Black or African American
2 Participants6 Participants8 Participants
Race/Ethnicity, Customized
Other
9 Participants17 Participants26 Participants
Race/Ethnicity, Customized
Unknown
14 Participants17 Participants31 Participants
Race/Ethnicity, Customized
White
199 Participants178 Participants377 Participants
Sex: Female, Male
Female
283 Participants288 Participants571 Participants
Sex: Female, Male
Male
1 Participants0 Participants1 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
deaths
Total, all-cause mortality
9 / 28412 / 288151 / 275156 / 275
other
Total, other adverse events
280 / 284244 / 2870 / 00 / 0
serious
Total, serious adverse events
110 / 28454 / 2870 / 00 / 0

Outcome results

Primary

Progression-free Survival (PFS) Per Investigator Assessment in the PIK3CA Mutant Cohort

PFS was defined as the time from the date of randomization to the date of the first documented progression or death due to any cause. PFS was assessed via a local radiology assessment according to RECIST 1.1. If a patient did not have an event, PFS was censored at the date of last adequate tumor assessment. The PFS distribution was estimated using Kaplan-Meier methodology. Progression was defined as at least a 20% increase in the sum of diameter of all measured target lesions, taking as reference the smallest sum of diameter of all target lesions recorded at or after baseline. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm.

Time frame: Once approximately 243 PFS events in the PIK3CA mutant cohort had been observed, up to 33.3 months

Population: All subjects with a PIK3CA mutation (based on central testing of hotspot-mutations in tumor tissue) who were randomized to study treatment

ArmMeasureValue (MEDIAN)
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantProgression-free Survival (PFS) Per Investigator Assessment in the PIK3CA Mutant Cohort11.0 Months
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantProgression-free Survival (PFS) Per Investigator Assessment in the PIK3CA Mutant Cohort5.7 Months
p-value: 0.0006595% CI: [0.5, 0.85]Log Rank
Secondary

Change From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30

The EORTC QLQ-C30 is a questionnaire that includes 5 functional scales, 3 symptom scales, 1 GHS/QoL scale, and 6 single items. GHS/QoL scale score ranges between 0 and 100. A high score for GHS/QoL represents better functioning or QoL.The change from baseline in the GHS/QoL score was assessed. A positive change from baseline indicated improvement. For each cohort, this analysis only included assessments up to the time point where there were at least 10 patients on each of the 2 treatment groups.

Time frame: Baseline, every 8 weeks after randomization during the first 18 months and thereafter every 12 weeks, up to 120 weeks.

Population: Randomized participants with baseline scores and at least one non-missing post-baseline assessment. Number analyzed refers to the number of participants with an evaluable value at the specified time point

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)Dispersion
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 16-1.796 Score on a ScaleStandard Error 2.349
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 64-1.937 Score on a ScaleStandard Error 2.835
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 56-1.617 Score on a ScaleStandard Error 2.701
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 40-2.815 Score on a ScaleStandard Error 2.581
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 8-2.477 Score on a ScaleStandard Error 2.286
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 48-3.635 Score on a ScaleStandard Error 2.621
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 108-2.158 Score on a ScaleStandard Error 3.328
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 96-3.869 Score on a ScaleStandard Error 3.054
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 24-3.010 Score on a ScaleStandard Error 2.415
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 120-2.928 Score on a ScaleStandard Error 3.251
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 84-1.135 Score on a ScaleStandard Error 2.958
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 72-2.525 Score on a ScaleStandard Error 2.823
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 32-2.802 Score on a ScaleStandard Error 2.519
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 120-2.593 Score on a ScaleStandard Error 3.868
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 8-0.369 Score on a ScaleStandard Error 2.324
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 16-2.685 Score on a ScaleStandard Error 2.455
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 24-0.337 Score on a ScaleStandard Error 2.587
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 32-0.891 Score on a ScaleStandard Error 2.646
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 40-1.854 Score on a ScaleStandard Error 2.739
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 48-1.460 Score on a ScaleStandard Error 2.853
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 560.248 Score on a ScaleStandard Error 2.935
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 64-1.979 Score on a ScaleStandard Error 2.984
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 72-1.526 Score on a ScaleStandard Error 3.098
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 84-1.495 Score on a ScaleStandard Error 3.143
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 96-3.581 Score on a ScaleStandard Error 3.423
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 108-2.068 Score on a ScaleStandard Error 3.609
PIK3CA Non-mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 81.524 Score on a ScaleStandard Error 2.578
PIK3CA Non-mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 241.383 Score on a ScaleStandard Error 3.087
PIK3CA Non-mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 162.866 Score on a ScaleStandard Error 2.809
PIK3CA Non-mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 321.063 Score on a ScaleStandard Error 3.42
PIK3CA Non-mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 4013.232 Score on a ScaleStandard Error 4.783
PIK3CA Non-mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 82.698 Score on a ScaleStandard Error 2.601
PIK3CA Non-mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 404.923 Score on a ScaleStandard Error 4.003
PIK3CA Non-mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 324.345 Score on a ScaleStandard Error 3.731
PIK3CA Non-mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 161.700 Score on a ScaleStandard Error 2.835
PIK3CA Non-mutant Cohort by Tumor Tissue: Placebo + FulvestrantChange From Baseline in the GHS/QOL Scale Score of the EORTC QLQ-C30Week 244.909 Score on a ScaleStandard Error 3.385
Secondary

Clinical Benefit Rate (CBR) Per Investigator Assessment

Clinical benefit rate was defined as the percentage of patients with a best overall response of CR or PR or stable disease (SD) or Non-CR/Non-PD lasting more than 24 weeks based on local investigator assessment according to RECIST 1.1. CR: Disappearance of all non-nodal target and non-target lesions. In addition, any pathological lymph nodes assigned as target and non-target lesions must have a reduction in short axis to \< 10 mm. PR: At least a 30% decrease in the sum of diameter of all target lesions, taking as reference the baseline sum of diameters. SD: Neither sufficient shrinkage to qualify for PR or CR nor an increase in lesions which would qualify for progressive disease.

Time frame: Up to 56.4 months

Population: All subjects who were randomized to study treatment.

ArmMeasureValue (NUMBER)
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantClinical Benefit Rate (CBR) Per Investigator Assessment61.5 Percentage of participants
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantClinical Benefit Rate (CBR) Per Investigator Assessment44.8 Percentage of participants
PIK3CA Non-mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantClinical Benefit Rate (CBR) Per Investigator Assessment53.9 Percentage of participants
PIK3CA Non-mutant Cohort by Tumor Tissue: Placebo + FulvestrantClinical Benefit Rate (CBR) Per Investigator Assessment49.1 Percentage of participants
Secondary

OS in the PIK3CA Non-mutant Cohort

OS was defined as the time from date of randomization to date of death due to any cause. If a patient was not known to have died, survival was censored at the date of last known date patient alive. The OS distribution was estimated using Kaplan-Meier methodology.

Time frame: Up to 56.4 months

Population: All subjects without a PIK3CA mutation (based on central testing of hotspot-mutations in tumor tissue) who were randomized to study treatment

ArmMeasureValue (MEDIAN)
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantOS in the PIK3CA Non-mutant Cohort37.29 Months
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantOS in the PIK3CA Non-mutant Cohort34.30 Months
Secondary

Overall Response Rate (ORR) Per Investigator Assessment

ORR was defined as the percentage of patients with best overall response of complete response (CR) or partial response (PR) based on local investigator's assessment according to RECIST 1.1. CR: Disappearance of all non-nodal target and non-target lesions. In addition, any pathological lymph nodes assigned as target and non-target lesions must have a reduction in short axis to \< 10 mm. PR: At least a 30% decrease in the sum of diameter of all target lesions, taking as reference the baseline sum of diameters.

Time frame: Up to 56.4 months

Population: All subjects who were randomized to study treatment.

ArmMeasureValue (NUMBER)
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantOverall Response Rate (ORR) Per Investigator Assessment26.6 Percentage of participants
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantOverall Response Rate (ORR) Per Investigator Assessment13.4 Percentage of participants
PIK3CA Non-mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantOverall Response Rate (ORR) Per Investigator Assessment20.9 Percentage of participants
PIK3CA Non-mutant Cohort by Tumor Tissue: Placebo + FulvestrantOverall Response Rate (ORR) Per Investigator Assessment12.9 Percentage of participants
Secondary

Overall Survival (OS) in the PIK3CA Mutant Cohort

OS was defined as the time from date of randomization to date of death due to any cause. If a patient was not known to have died, survival was censored at the date of last known date patient alive. The OS distribution was estimated using Kaplan-Meier methodology.

Time frame: Once approximately 178 deaths in the PIK3CA mutant cohort had been observed, up to 55.7 months

Population: All subjects with a PIK3CA mutation (based on central testing of hotspot-mutations in tumor tissue) who were randomized to study treatment

ArmMeasureValue (MEDIAN)
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantOverall Survival (OS) in the PIK3CA Mutant Cohort39.3 Months
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantOverall Survival (OS) in the PIK3CA Mutant Cohort31.4 Months
Secondary

PFS Per Investigator Assessment in the PIK3CA Non-mutant Cohort

PFS was defined as the time from the date of randomization to the date of the first documented progression or death due to any cause. PFS was assessed via a local radiology assessment according to RECIST 1.1. If a patient did not have an event, PFS was censored at the date of last adequate tumor assessment. The PFS distribution was estimated using Kaplan-Meier methodology. Progression was defined as at least a 20% increase in the sum of diameter of all measured target lesions, taking as reference the smallest sum of diameter of all target lesions recorded at or after baseline. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm.

Time frame: Up to 56.4 months

Population: All subjects without a PIK3CA mutation (based on central testing of hotspot-mutations in tumor tissue) who were randomized to study treatment

ArmMeasureValue (MEDIAN)
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantPFS Per Investigator Assessment in the PIK3CA Non-mutant Cohort7.43 Months
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantPFS Per Investigator Assessment in the PIK3CA Non-mutant Cohort7.23 Months
Secondary

PFS Per Investigator Criteria in Subjects With PIK3CA Mutation Status Measured in ctDNA at Baseline

PFS was defined as the time from the date of randomization to the date of the first documented progression or death due to any cause. PFS was assessed via a local radiology assessment according to RECIST 1.1. If a patient did not have an event, PFS was censored at the date of last adequate tumor assessment. The PFS distribution was estimated using Kaplan-Meier methodology. Subjects were analyzed according to the PIK3CA mutation status (mutant or non-mutant) as identified using plasma ctDNA. Progression was defined as at least a 20% increase in the sum of diameter of all measured target lesions, taking as reference the smallest sum of diameter of all target lesions recorded at or after baseline. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm.

Time frame: From baseline up to 56.4 months

Population: Subjects who were randomized to study treatment with an evaluable mutation status by ctDNA at baseline

ArmMeasureValue (MEDIAN)
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantPFS Per Investigator Criteria in Subjects With PIK3CA Mutation Status Measured in ctDNA at Baseline10.9 Months
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantPFS Per Investigator Criteria in Subjects With PIK3CA Mutation Status Measured in ctDNA at Baseline3.7 Months
PIK3CA Non-mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantPFS Per Investigator Criteria in Subjects With PIK3CA Mutation Status Measured in ctDNA at Baseline9.0 Months
PIK3CA Non-mutant Cohort by Tumor Tissue: Placebo + FulvestrantPFS Per Investigator Criteria in Subjects With PIK3CA Mutation Status Measured in ctDNA at Baseline7.4 Months
Secondary

Time to 10% Deterioration in the Global Health Status (GHS) /Quality of Life (QOL) Scale Score of the European Organization for Research and Treatment of Cancer's Core Quality of Life Questionnaire (EORTC QLQ-C30)

The EORTC QLQ-C30 is a questionnaire that includes 5 functional scales, 3 symptom scales, 1 GHS/QoL scale, and 6 single items. GHS/QoL scale score ranges between 0 and 100. A high score for GHS/QoL represents better functioning or QoL.The time to definitive 10% deterioration was defined as the time from the date of randomization to the date of event, which was defined as at least 10% relative to baseline worsening of the GHS/QoL score (without further improvement above the threshold) or death due to any cause. The Kaplan-Meier method was used to estimate the distribution. If a patient had not had an event, time to deterioration was censored at the date of the last adequate QoL evaluation.

Time frame: From baseline up to 55.7 months

Population: All subjects who were randomized to study treatment

ArmMeasureValue (MEDIAN)
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTime to 10% Deterioration in the Global Health Status (GHS) /Quality of Life (QOL) Scale Score of the European Organization for Research and Treatment of Cancer's Core Quality of Life Questionnaire (EORTC QLQ-C30)18.14 Months
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantTime to 10% Deterioration in the Global Health Status (GHS) /Quality of Life (QOL) Scale Score of the European Organization for Research and Treatment of Cancer's Core Quality of Life Questionnaire (EORTC QLQ-C30)19.98 Months
PIK3CA Non-mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTime to 10% Deterioration in the Global Health Status (GHS) /Quality of Life (QOL) Scale Score of the European Organization for Research and Treatment of Cancer's Core Quality of Life Questionnaire (EORTC QLQ-C30)7.39 Months
PIK3CA Non-mutant Cohort by Tumor Tissue: Placebo + FulvestrantTime to 10% Deterioration in the Global Health Status (GHS) /Quality of Life (QOL) Scale Score of the European Organization for Research and Treatment of Cancer's Core Quality of Life Questionnaire (EORTC QLQ-C30)9.23 Months
Secondary

Time to Definitive Deterioration of Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) Score From Baseline

ECOG PS categorized patients based on their ability to perform daily activities and self-care, with scores ranging from 0 to 5. A score of 0 indicated no restrictions in activity, while higher scores indicated increasing limitations. Time to definitive deterioration of ECOG PS by one score was defined as the time from the date of randomization to the date of the event, defined as experiencing at least one score lower than the baseline. A deterioration was considered definitive if no improvements in the ECOG PS were observed at a subsequent time. The Kaplan-Meier method was used to estimate the distribution. Patients receiving any further therapy prior to definitive worsening were censored at their date of last assessment prior to start of therapy. Patients that had not worsened at the data cutoff point were censored at the date of last assessment.

Time frame: From baseline up to 56.4 months

Population: All subjects who were randomized to study treatment

ArmMeasureValue (MEDIAN)
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTime to Definitive Deterioration of Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) Score From Baseline34.07 Months
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantTime to Definitive Deterioration of Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) Score From BaselineNA Months
PIK3CA Non-mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTime to Definitive Deterioration of Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) Score From BaselineNA Months
PIK3CA Non-mutant Cohort by Tumor Tissue: Placebo + FulvestrantTime to Definitive Deterioration of Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) Score From Baseline40.44 Months
Secondary

Trough Plasma Concentration of Alpelisib

Pre-dose plasma concentrations of alpelisib were assessed. Only participants randomized to the alpelisib + fulvestrant arm were included in this analysis.

Time frame: Day 8 and Day 15 of Cycle 1, then Day 1 of Cycles 2, 4, 6 and 8. Cycle = 28 days

Population: Participants who received at least one dose of alpelisib and provided at least one evaluable trough plasma concentration for alpelisib at the specified time points

ArmMeasureGroupValue (GEOMETRIC_MEAN)Dispersion
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTrough Plasma Concentration of AlpelisibCycle 1 Day 8424 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 41.1
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTrough Plasma Concentration of AlpelisibCycle 4 Day 1458 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 69.4
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTrough Plasma Concentration of AlpelisibCycle 1 Day 15468 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 57.6
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTrough Plasma Concentration of AlpelisibCycle 2 Day 1436 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 53.4
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTrough Plasma Concentration of AlpelisibCycle 6 Day 1418 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 57.1
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTrough Plasma Concentration of AlpelisibCycle 8 Day 1469 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 58.3
Secondary

Trough Plasma Concentration of Fulvestrant

Pre-dose plasma concentrations of fulvestrant were assessed.

Time frame: Day 15 of Cycle 1, then Day 1 of Cycles 2, 4, 6 and 8. Cycle = 28 days

Population: Participants who received at least one dose of fulvestrant and provided at least one evaluable trough plasma concentration for fulvestrant at the specified time points

ArmMeasureGroupValue (GEOMETRIC_MEAN)Dispersion
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTrough Plasma Concentration of FulvestrantCycle 2 Day 114.0 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 39.7
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTrough Plasma Concentration of FulvestrantCycle 6 Day 112.6 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 30.5
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTrough Plasma Concentration of FulvestrantCycle 4 Day 111.5 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 32.2
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTrough Plasma Concentration of FulvestrantCycle 8 Day 113.5 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 35.2
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantTrough Plasma Concentration of FulvestrantCycle 1 Day 1510.8 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 43.5
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantTrough Plasma Concentration of FulvestrantCycle 8 Day 114.7 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 23.2
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantTrough Plasma Concentration of FulvestrantCycle 1 Day 1510.3 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 51
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantTrough Plasma Concentration of FulvestrantCycle 2 Day 114.7 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 41.2
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantTrough Plasma Concentration of FulvestrantCycle 4 Day 112.2 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 29.8
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantTrough Plasma Concentration of FulvestrantCycle 6 Day 114.0 nanogram (ng)/ milliliter (mL)Geometric Coefficient of Variation 24.2
Post Hoc

All Collected Deaths

Pre-treatment deaths were collected from randomization to the day before first dose of study medication. On-treatment deaths were collected from start of treatment to 30 days after last dose of study medication. Post-treatment survival follow-up deaths were collected from day 31 after last dose of study treatment to end of study.

Time frame: Pre-treatment: Up to 35 days. On-treatment: Up to approx. 6.5 years. Post-treatment survival follow-up: Up to approx. 6.5 years

Population: All subjects who were randomized to study treatment.

ArmMeasureGroupValue (NUMBER)
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantAll Collected DeathsPre-treatment0 Participants
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantAll Collected DeathsOn-treatment9 Participants
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantAll Collected DeathsPost-treatment survival follow-up151 Participants
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantAll Collected DeathsAll deaths160 Participants
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantAll Collected DeathsAll deaths168 Participants
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantAll Collected DeathsPre-treatment0 Participants
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantAll Collected DeathsPost-treatment survival follow-up156 Participants
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantAll Collected DeathsOn-treatment12 Participants
Other Pre-specified

Updated PFS Per Investigator Assessment in the PIK3CA Mutant Cohort (Longer Follow-up)

PFS was defined as the time from the date of randomization to the date of the first documented progression or death due to any cause. PFS was assessed via a local radiology assessment according to RECIST 1.1. If a patient did not have an event, PFS was censored at the date of last adequate tumor assessment. The PFS distribution was estimated using Kaplan-Meier methodology. This analysis was conducted at the time of the final OS analysis (when approximately 178 deaths in the PIK3CA mutant cohort had been achieved) and includes a longer follow-up time. Progression was defined as at least a 20% increase in the sum of diameter of all measured target lesions, taking as reference the smallest sum of diameter of all target lesions recorded at or after baseline. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm.

Time frame: Up to 55.7 months

Population: All subjects with a PIK3CA mutation who were randomized to study treatment

ArmMeasureValue (MEDIAN)
PIK3CA Mutant Cohort by Tumor Tissue: Alpelisib + FulvestrantUpdated PFS Per Investigator Assessment in the PIK3CA Mutant Cohort (Longer Follow-up)10.97 Months
PIK3CA Mutant Cohort by Tumor Tissue: Placebo + FulvestrantUpdated PFS Per Investigator Assessment in the PIK3CA Mutant Cohort (Longer Follow-up)5.65 Months

Source: ClinicalTrials.gov · Data processed: Mar 5, 2026