Many cytotoxic drugs may harm the fertility of young women treated for cancer. The aim of the study is to investigate if the Gonadotropin-Releasing Hormone agonist (GnRHa) during cancer treatment can preserve the fertility of young female cancer subjects.

Approximately 300 women with newly diagnosed breast cancer and up to 200 women with newly diagnosed lymphoma, acute leukemias or sarcomas will be recruited before start of cancer treatment.

The patients will be randomised in between treatment with triptorelin (experimental) or placebo (control) intramuscularly a 1:1 ratio during chemotherapy. The injections may be given once monthly or once three months depending on type of chemotherapy given. Randomisation and study drug is blinded, neither investigator, research nurse nor patient will know if it is active drug or placebo. The only person who knows is the nurse preparing the injection.

Patients will be followed up to 5 years after end of treatment with physical examinations, vital signs, biochemical markers, bone mineral density exams, ultrasound for antral follicle counts and ovarian doppler flow, concomitant medications, adverse events and quality of life questionnaires.

Inclusion Criteria:

• Signed informed consent
• Breast cancer or acute leukemias, lymphomas (Hodgkin and non-Hodgkin) or sarcomas (osteo, soft tissue and Ewing) confirmed by histology and assigned for diseace-specific chemotheraphy
• Confirmed menarche
• ECOG performance status 0-1
• Adequate bone marrow, renal, hepatic and cardiac functions and absence of other uncontrolled medical or psychiatric disorders

Exclusion Criteria:

• Demonstrated premature ovarian failure at time of randomization according to clinical or biochemical data
• Previous or planned bilateral oophorectomy
• Pregnancy or breastfeeding at time of start of chemotherapy
• Other malignancy diagnosed within the last five years
• Uncontrolled hypertension, heart, liver, kidney related or other uncontrolled medical or psychiatric disorders including previous or current diagnosis of anorexia
• Known osteoporosis
• Known low platelet count with increased bleeding risk or refractory thrombocytopenia in subjects with acute leukemias
• Known or suspected allergy against triptorelin
• Direct radiation of the gonads previous or planned (TBI allowed)
• Mental inability, reluctance or language difficulties that result in difficulty understanding the meaning of study participation

The identity of the individual participants is protected by GDPR through the The Swedish Authority for Privacy Protection as regulated by the informed consent and any data sharing must be in accordance with their regulations. We can thus only share IPD that underlie the results reported in this study (text, tables, figures, and appendices), after full anonymization of the data.

After completion of the study the protocol, informed consent form and statistical analysis plan will be available.

Requests for additional analyses or to access the anonymized datasets should be directed to kenny.rodriguez-wallberg@ki.se. Information will be available upon reasonable request to the sponsor and if in correspondence with the proposed research in the signed informed consent e.g to achieve aims in the approved proposal.

Subjects are randomised to triptorelin (active arm) or placebo (control) given in parallel to the chemotherapy treatment for the cancer diagnosis. All personnel involved in the study, and subjects, except personnel preparing triptorelin/placebo at the local site and an unblinded monitor, will be blinded during the study. Unblinded research nurse at each site will prepare blinded triptorelin/placebo to subjects and a web-based randomisation system will be used to allocate of blinded triptorelin/placebo to subjects at randomisation and drug dispense during the treatment period.