This is a multicenter, Phase 1b/2 trial in participants with estrogen receptor positive/human epidermal growth factor receptor 2 negative (ER+/HER2-) advanced/metastatic breast cancer. The phase 1b part of the trial will determine the recommended Phase 2 dose (RP2D) of elacestrant when administered in combination with alpelisib, everolimus, palbociclib, capivasertib, and ribociclib. The Phase 2 part of the trial will evaluate the efficacy and safety of the various combinations.
This is a multicenter, Phase 1b/2 trial. The Phase 1b aims at selecting the RP2D dose, defined as a dose that is associated with less than 33% of participants experiencing a dose-limiting toxicity (DLT) of elacestrant when administered in combination with alpelisib, everolimus, palbociclib, ribociclib, and capivasertib that is, ≤1 participant experiencing a DLT out of 6 DLT-evaluable participants. For each combination, this phase will have approximately 3 cohorts of up to 6 DLT-evaluable participants each. The total number of DLT-evaluable participants in all the combinations will be up to 125. The Phase 2 part of the trial will evaluate the efficacy and safety of the various combinations. The treatment arms will be: * Arm A: 50 participants: elacestrant with alpelisib; * Arm B: 50 participants: elacestrant with everolimus; * Arm C: 60 participants (30 participants in each combination): elacestrant with either abemaciclib or ribociclib; * Arm D: 90 participants (30 participants in each combination): elacestrant with either palbociclib, abemaciclib, or ribociclib; * Arm E: 60 participants: elacestrant with capivasertib Phase 1b will have a total of 125 participants, while Phase 2 will have 310 participants for all treatment arm combinations.
Elacestrant 86 mg, 172 mg, 258 mg or 345 mg once daily in cycles of 28 days
Alpelisib 150 mg or 250 mg once daily in cycles of 28 days
Everolimus 5 mg, 7.5 mg, or 10 mg once daily in cycles of 28 days
Ribociclib 400 mg or 600 mg once daily for 21 days followed by 7 days off in cycles of 28 days
Palbociclib 100 mg or 125 mg once daily for 21 days followed by 7 days off in cycles of 28 days
Capivasertib 200 mg or 320 mg or 400 mg twice daily for 4 days on, 3 days off in cycles of 28 days
Abemaciclib 100 mg or 150 mg twice daily in cycles of 28 consecutive days
Buenos Aires, Argentina
Guillermo Streich
Buenos Aires, Argentina
Córdoba, Argentina
Jorge Emilio Salinas
La Rioja, Argentina
Diego Lucas Kaen