A Study of Tucatinib or Placebo With Trastuzumab and Pertuzumab for Metastatic HER2+ Breast Cancer

Condition(s) studied

Investigational drug(s) / intervention(s)

Tucatinib: 300mg given by mouth (orally) twice daily

Trastuzumab: 6mg/kg given into the vein (IV; intravenously) or 600mg injected under the skin (SC; subcutaneous) every 21 days

Pertuzumab: 420mg given by IV every 21 days

Combination product: Trastuzumab + Pertuzumab: 600 mg pertuzumab, 600 mg trastuzumab, and 20,000 units hyaluronidase will be given by subcutaneous injection every 21 days. May be given in place of trastuzumab and pertuzumab individually.

Placebo: Given orally twice daily

Study summary

This study is being done to see if tucatinib works better than placebo when given with other drugs to treat participants with HER2-positive breast cancer. A placebo is a pill that looks the same as tucatinib but has no medicine in it. This study will also test what side effects happen when participants take this combination of drugs. A side effect is anything a drug does to the body besides treating your disease.

Participants will have cancer that has spread in the body near where it started (locally advanced) and cannot be removed (unresectable) or has spread through the body (metastatic).

In this study, all participants will get either tucatinib or placebo. Participants will be assigned randomly to a group. This is a blinded study, so patients and their doctors will not know which group a participant is in.

All participants will also get trastuzumab and pertuzumab. These are 2 drugs used to treat this type of cancer.

Eligibility

Primary outcome measure(s)

• Progression-Free Survival (PFS) as Assessed by Investigator Per Response Evaluation Criteria in Solid Tumors (RECIST) Version (v) 1.1 — From randomization until the first documentation of PD or death from any cause or censoring date, whichever occurred first (maximum treatment exposure was of 41.3 months)
  PFS: time from randomization to the first documented disease progression (PD) (as assessed by investigator per RECIST 1.1) or death from any cause, whichever occurred first. PD: \>=20% increase in sum of diameters of target lesions, taking as reference the smallest sum of diameter recorded since the treatment started or the appearance of 1 or more new lesions. Participants without documentation of PD/ death at the time of analysis, were censored at date of last tumor assessment with an overall response of complete response (CR), partial response (PR), stable disease (SD), non-CR/non-PD or no evidence of disease (NED). CR: disappearance of all target lesions; PR: \>=30% decrease in the sum of the diameters of target lesions, taking as reference the baseline sum of diameters; SD: neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for PD, taking as reference the smallest sum of diameter since the treatment started. Kaplan-Meier method was used for analysis.

Trial sites (307)

+ 267 more sites — see the full list on the official registry below.

On this site

More Seagen, a wholly owned subsidiary of Pfizer trials in Spain

Other trials for the same condition