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GBG Forschungs GmbH – a leading breast cancer research institute

Please note our new address from July 18, 2022:
GBG Forschungs GmbH • Dornhofstraße 10 • 63263 Neu-Isenburg

Breast cancer research – independent, academic, impartial

GBG Forschungs GmbH is an independent, impartial academic research organisation (ARO). Unlike contract research organisations (CRO), we do not provide research services purely on a contract basis. All study projects have to address an academic question which meets the requirements of the German Breast Group. Through our research, we aim to continually improve the treatment of breast cancer and the quality of the therapy available on a global basis.

Independent breast cancer research – an international leader

When conducting our breast cancer research projects, we adhere to the principles of international academic study groups. Our research institute, together with the German Breast Group’s sub-boards, creates the protocols for our studies as well as our databases and is also responsible for their evaluation and publication – always without influence from the pharmaceutical industry. Examples of our research are the neoadjuvant studies belonging to the “Gepar” trial series.

Today, GBG Forschungs GmbH has clinical data from more than 55,000 breast cancer patients at its disposal. Thanks to our expertise and experience acquired through 30 years of research, we are one of the world’s leading breast cancer research institutes.

Funding of breast cancer research

Our research projects are funded in advance via clinical trials, donations, public funding, the German Cancer Aid Organisation (Deutsche Krebshilfe) and the German Research Foundation (Deutsche Forschungsgemeinschaft). In addition, we receive funding from the German Federal Ministry of Education and Research (Bundesministerium für Bildung und Forschung ─ BMBF) and from foundations, such as the Banss-Stiftung, the Walter-Schulz-Stiftung and the Claudia-von-Schilling-Stiftung, as well as cooperation partners from the pharmaceutical industry. Our Translational Research Division is predominantly funded by the EU, the German Federal Government and various foundations.


German Breast Group: An employer for your future. We are recruiting to expand our multidisciplinary team. Get more information about our current vacancies here.


Do you have any questions about breast cancer? In our patient guide you will find comprehensive information and links to specialized self-help resources.


GBG Study Finder 2022

Overview of our currently recruiting trials. Further studies are in planning.

Early Breast Cancer

Operative Studies (M0)

Operable node-positive breast cancer:

  • Most suspicious lymph node clipped
  • AJCC/UICC stage II-III
  • Eligible for primary axillary lymph node dissection or sentinel lymph node biopsy procedure

Tailored axillary surgery with or without axillary lymph node dissection followed by radiotherapy. All patients will receive breast/chest wall and regional nodal irradiation. Patients without axillary lymph node dissection will receive additional irradiation of the axilla.


Operable HER2-positive or triple-negative breast cancer:

  • cT1c-T3 prior to neoadjuvant systemic therapy (NAST) and
  • cN0/iN0
  • Standard NAST with radiological complete response

Omission of sentinel lymph node biopsy in patients with radiologic and pathologic complete response in the breast after neoadjuvant systemic therapy. All patients with confirmed breast pCR after lumpectomy will be selected for the single study arm leading to omission of any axillary treatment.


(Neo)adjuvant Studies (M0)

Operable triple-negative breast cancer:

  • Stage II-III
  • Pathological tumor size >2 cm if pN0

Arm A: Adjuvant chemotherapy with 12x paclitaxel weekly followed by EC/AC q2w + atezolizumab q2w followed by atezolizumab monotherapy q3w (total duration of atezolizumab will be one year)
Arm B: Chemotherapy alone


Operable HR-positive / HER2-negative breast cancer:

  • Age ≥ 70 years; Stage II-III
  • Adjuvant chemotherapy required and feasible

Arm A: Palbociclib 2 years + standard adjuvant endocrine therapy ≥ 5 years
Arm B: Adjuvant chemotherapy followed by standard adjuvant endocrine therapy ≥ 5 years


HER2-negative breast cancer, non-pCR after NACT

  • HR-negative (TNBC)


  • HR-positive with CPS-EG score ≥3 or 2 and ypN+
  •  At least 16 weeks of taxane-based chemotherapy

Arm A: Sacituzumab govitecan 8 cycles d1,8 q3w
Arm B: Treatment of physician`s choice (8 cycles capecitabine or platinum-based chemotherapy or observation)
In patients with HR-positive breast cancer, endocrine therapy will be administered according to local guidelines.


HER2-positive breast cancer, non-pCR after NACT

  • cT4, cN0-3 or cT1-3, cN2-3 at first diagnosis


  • cT1-3, cN0-1 at first diagnosis with ypN1-3 after NACT
  • An interval of ≤12 weeks between the date of last surgery and the date of randomization
  • At least 16 weeks chemotherapy, including at least 9 weeks of trastuzumab (± pertuzumab) and at least 9 weeks of taxane-based chemotherapy

Arm A: Trastuzumab deruxtecan 14 cycles d1 q3w
Arm B: Trastuzumab emtansine (T-DM1) 14 cycles d1 q3w


HER2-positive, HR-positive breast cancer

  • cT1c-T3 prior to neoadjuvant treatment
  • Centrally confirmed PIK3CA mutation (tumor)
  • BMI ≤ 30

Arm A: Endocrine therapy in combination with ready-to-use fixed-dose combination of pertuzumab and trastuzumab s.c. (PH-FDC SC) q3w and inavolisib (6 cycles)
Arm B: Endocrine therapy and PH-FDC SC q3w (6 cycles)


Metastatic Breast Cancer

All subtypes

Brain metastases of breast cancer

Brain Metastases in Breast Cancer (BMBC)
Retrospective and prospective registry designed to collect tumor characteristics of the primary and metastatic tumor as well as treatment data and biomaterial from patients diagnosed with brain metastases of breast cancer.


HER2-negative Breast Cancer

HER2-negative and HR-positive metastatic breast cancer :

  • 1st systemic therapy for the treatment of metastatic breast cancer
  • Patients with only asymptomatic oligometastases of the bone as the only site of metastatic disease are excluded

Endocrine therapy + palbociclib versus mono-chemotherapy +/- endocrine maintenance therapy
Possible mono-chemotherapies (Physician`s choice):

  • Capecitabine p.o.
  • Epirubicin i.v.
  • Paclitaxel i.v.
  • Vinorelbine i.v.

Breast Cancer in Special Situations

Pregnancy and Young Women

  • Patients with breast cancer during pregnancy
    Non-pregnant women with breast cancer < 40 years
    M1 possible
Prospective and retrospective registry study for the diagnosis and treatment of breast cancer in pregnancy compared to young non-pregnant women.


  • Women with a confirmed or likely deleterious BRCA1 germline mutation
  • Age ≥ 25 years and ≤ 55 years
  • No evidence of breast cancer
    No preventive breast surgery planned
  • No previous history of breast or ovarian cancer

Study to determine the preventive effect of denosumab on breast cancer in women carrying a BRCA1 germline mutation:
Denosumab 120mg s.c. every 6 months vs placebo s.c. every 6 months



Long-term Safety and Efficacy

Former GBG study participants in Germany

Patient self-reported outcome registry (PSRO)
Collection of long-term safety and efficacy parameters of former GBG study participants from prospective clinical trials. Data reporting by the patient via questionnaire.


Former GBG study participants other countries

Registry for collection of long-term safety and efficacy parameters of former GBG study participants from prospective clinical trials. Data collection and documentation is performed study site.


** Planned start of recruitment QI-II/2022


GBG Forschungs GmbH
Dornhofstr. 10 | 63263 Neu-Isenburg | Fax +49 6102 7480-440

+49 6102 7480-0 | nfGBGd