About this trial

The purpose of this trial is to determine the safety and efficacy of the drug copanlisib and the optimum dose when used with trastuzumab.

It will also establish how well copanlisib works in combination with trastuzumab to treat anti HER2-therapy resistant breast cancer. The study will also be used to learn more about this new drug and this type of cancer.

HER2+ breast cancer is a type of breast cancer that over-produces Human Epidermal growth factor Receptor 2 (HER2), a protein that stimulates the growth of cancer cells.

Currently, approved treatments that specifically target HER2, such as trastuzumab, are effective at helping to slow or even stop the growth of breast cancer cells. However, resistance to HER2-targeted treatment can develop, meaning that treatment is no longer effective. We are now learning how this happens. The switching on of a pathway called the PI3K pathway in cancer cells is often responsible. One of the possible ways this happens is through mutations (changes) that occur in a gene called PIK3CA. Research studies have suggested that blocking the abnormal activity of the PI3K pathway, may help to reverse the resistance of some HER2+ breast cancers to HER2 treatments.

Copanlisib is a new drug that blocks the abnormal activity in the PI3K pathway and it is currently being tested in a variety of cancers. By giving copanlisib and trastuzumab together, this research study hopes to block the abnormal activity of the PI3K pathway (using copanlisib) to allow trastuzumab to work. This will provide a new therapy for advanced previously treated HER2+ breast cancer.

Patient Profile

Patients who have advanced HER2-positive (HER2+) breast cancer that has progressed or has recurred either during or following anti-HER2 treatment.

Where’s this trial being run?

Beaumont Hospital, Cork University Hospital, St James’s Hospital, St Vincents University Hospital, and University Hospital Galway

Can I join this study / trial?

The first thing you do is to talk to your doctor and/or the cancer trials research team in your hospital. The contact details for the cancer trials research units in Ireland is here.

Why not Print this page and bring it with you. It will help your doctor and research team advise you.

For more detailed information


Here’s a list of questions you may have for your doctor or local cancer research team.

Summary Data

Name: PantHER
Number: 15-02
Full Title:

Phase Ib/II Clinical Trial of Copanlisib in Combination With Trastuzumab in Pretreated Recurrent or Metastatic HER2-positive Breast Cancer

Principal Investigator: Prof Bryan Hennessy (Beaumont Hospital)
Type: In-House

Cancer Trials Ireland

Recruitment Started: Global: Not Applicable
Ireland: August 2016
Global Recruitment Target: Not Applicable
Ireland Recruitment Target: 31