A study of tucatinib versus placebo in combination with pertuzumab and trastuzumab for subjects with advanced or metastatic HER2+ breast cancer

You may be able to join if

• Have centrally confirmed HER2+ breast carcinoma according to the 2018 American Society of Clinical Oncologists (ASCO)-College of American Pathologists (CAP) guidelines prior to randomization (defined as a 3+ score on immunohistochemistry (IHC) and/or 2+ IHC and concurrent positive by ISH). a. Tissue blocks or tumor slides must be submitted and confirmed as HER2+ by a sponsor designated central laboratory prior to randomization
• Have unresectable locally advanced or metastatic (hereafter referred to as “advanced”) disease; if recurrent (after [neo]adjuvant therapy), there must be a minimum 6month -treatment f-ree interval from any trastuzumab and pertuzumab received in the early breast cancer setting to the diagnosis of advanced HER2+ disease. Prior standard of care therapy for early breast cancer is permitted (eg, prior ado-trastuzumab- emtansine [T-DM1]); however, Exclusion Criterion 1 should be noted.
• Have received 4-8 cycles of pre-study induction therapy including only trastuzumab, pertuzumab, and taxane as first-line therapy for the treatment of advanced breast cancer prior to study enrollment. Participants are eligible provided they are without evidence of disease progression (per investigator judgement, ie, CR, PR, or SD) following completion of induction therapy. o Participants receiving <6 cycles (ie, 4-5 cycles) of taxane are only eligible if the taxane was stopped early due to intolerable toxicity (eg, documented neuropathy impacting function). o Participants are permitted to receive trastuzumab and pertuzumab for 2 additional cycles (after completion of chemotherapy) to allow completion of screening procedures. Study treatment should begin within 6 weeks (± 3 days) from the start of the last cycle of trastuzumab and pertuzumab. o Participants are permitted to receive up to 2 cycles of carboplatin during the start of induction therapy in combination with trastuzumab, pertuzumab, and taxane (eg, to obtain confirmation of metastatic breast cancer diagnosis) o Participants who received traditional medications (eg, traditional Chinese medication) and/or supplements with potential anti-cancer effects during induction therapy will remain eligible if they discontinue these treatments at least 4 weeks prior to the start of study treatment.
• Known hormone receptor status (per local guidelines; may be hormone receptor positive [HR+] or negative [HR-])
• Have Eastern Cooperative Oncology Group Performance Status (ECOG PS) of 0 or 1
• CNS Inclusion – Based on screening contrast-enhanced brain magnetic resonance imaging (MRI), participants may have any of the following: o No evidence of brain metastases o Untreated brain metastases which are asymptomatic, not needing immediate local treatment and, if identified on prior brain imaging, without evidence of progression since starting first-line induction therapy with trastuzumab, pertuzumab, and taxane o Previously treated brain metastases which are asymptomatic o Brain metastases previously treated with local therapy must not have progressed since treatment o Time since whole brain radiation therapy (WBRT) is ≥ 14 days prior to first dose of study treatment, time since stereotactic radiosurgery (SRS) is ≥7 days prior to first dose of study treatment, or time since surgical resection is ≥28 days prior to first dose of study treatment o Relevant records of any CNS treatment must be available to allow for classification of target and non-target lesions