AstraZeneca has yet to elaborate on its ‘commercial’ decision to discontinue a medication used by thousands of breast cancer and endometriosis patients.
Mystery surrounds why pharmaceutical giant AstraZeneca would withdraw a successful medication used by thousands of Australian cancer and endometriosis patients, leaving clinicians, patient groups and government officials searching for answers.
The company has described its move to discontinue the goserelin 3.6mg implant (Zoladex Implant) in Australia, removing it from both the Pharmaceutical Benefits Scheme (PBS) and the private market, simply as a “commercial” decision.
It has clearly stated that the decision was unrelated to the product’s safety, efficacy or quality, but provided no public explanation of the commercial factors that prompted the move.
The Medical Republic today sent an extensive list of questions to AstraZeneca about the decision, including “What specific commercial factors led AstraZeneca to discontinue Zoladex 3.6mg in Australia?”
We received this response from an AstraZeneca spokesperson to our 16 questions:
“AstraZeneca is discontinuing ZOLADEX® (goserelin) monthly (3.6mg) implant from Australia. The ZOLADEX monthly implant will not be available on the Pharmaceutical Benefits Scheme (PBS) and will also not be available for patients to purchase via a private prescription from November 2026,” they said.
“The discontinuation of ZOLADEX monthly implant from the Australian market is not related to the safety or efficacy of ZOLADEX.
“The ZOLADEX® (goserelin) three monthly implant (10.8mg) will remain available to Australian patients.
“AstraZeneca has prepared government regulatory and reimbursement applications to expand availability and access of ZOLADEX three monthly implant to include breast cancer patients that are hormone receptor positive as soon as possible.
“We understand that maintaining continuity of care is essential for patients who need access to the ZOLADEX monthly implant as a treatment option. For eligible patients without alternative treatment pathways, AstraZeneca will provide free access to the ZOLADEX monthly implant in Australia following its discontinuation in Australia from 1 November 2026.”
Related
Some media outlets have reported that this compassionate access has been set at six months from that date. AstraZeneca did not respond to a TMR question about this.
The lack of detail has fuelled concern and a mainstream media storm involving worried patients because the withdrawal affects a medicine that many clinicians regard as a cornerstone therapy for hormone-sensitive conditions, including prostate cancer, endometriosis and hormone receptor-positive breast cancer.
It has also placed the federal government in the unusual position of publicly acknowledging that it attempted to keep the product on the PBS but was ultimately unable to do so.
“The Australian government appreciates that it is important for Australians to have access to the medicines they need,” a statement from the PBS said.
“The government relies on the advice of the Pharmaceutical Benefits Advisory Committee (PBAC) about the removal of medicines from the PBS. The PBAC has advised that the delisting of this product will result in unmet clinical need.
“Alternative options remain listed on the PBS, including goserelin 10.8mg implant (Zoladex 10.8 Implant™) and other gonadotropin-releasing hormone (GnRH) agonists for the prostate cancer and endometriosis indications.
“However, it is recognised that there are currently no other PBS listed options for hormone receptor positive breast cancer and anticipated premature ovarian failure.”
Speculation about the rationale for AstraZeneca’s decision has centred on the economics of supplying a relatively small market.
Writing in The Conversation, Professor Nial Wheate, of Macquarie University’s School of Natural Sciences, noted that Australia accounted for only a small share of global medicine demand and suggested factors such as manufacturing priorities, cost pressures or the desire to streamline product lines may have influenced the company’s thinking.
AstraZeneca has not publicly confirmed any of these factors.
“AstraZeneca – the company that produces Zoladex – has decided to pull its low-dose medication from the Australian market for ‘commercial reasons’,” Professor Wheate wrote.
“The company has stated these are unrelated to the drug’s safety or efficacy but has not explained what the exact reasons are.
“However, one possible factor could be a difference in demand for low-dose Zoladex in Australia versus overseas.
“In 2025, there were nearly 100,000 scripts for the medication across the country. But for a company such as AstraZeneca, it may be more profitable to go from producing two products to one, particularly in the Australian market which makes up just 2.1% of the total global demand for medicines.
“However, other factors may also have contributed to AstraZeneca’s latest decision. It may be looking to cut costs, or free up manufacturing capacity to start producing a new medicine or increase supply of an existing medicine.”
AstraZeneca has indicated that the three-monthly 10.8mg implant will remain available and that applications have been submitted to expand its approved indications and PBS reimbursement to include hormone receptor-positive breast cancer.
Any such expansion would need to undergo assessment by the Therapeutic Goods Administration and PBAC before approval.
The withdrawal has generated concern among breast cancer specialists because ovarian suppression with monthly goserelin is commonly used in premenopausal women with hormone receptor-positive disease.
These cancers rely on oestrogen to grow, and reducing hormone levels can significantly improve outcomes when used alongside endocrine therapies. Although alternative treatment approaches exist, clinicians note that not all patients can be readily switched to another regimen.
Endometriosis patients may also be affected. By suppressing oestrogen production, goserelin can reduce inflammation and pain associated with the condition. Other hormonal treatments, including contraceptives and progestogen-based therapies, may be suitable alternatives for some women, but treatment decisions are highly individualised.
For some observers, however, the support program has raised further questions about the rationale for discontinuing the medicine in the first place.
If the company could continue supplying the product through a compassionate access arrangement it remained unclear why routine PBS and private market access could no longer be maintained.
The department has encouraged all patients currently receiving goserelin 3.6mg to discuss treatment options with their healthcare team well before the November 2026 deadline.
Clinicians have similarly been urged to identify affected patients early and consider whether transition to alternative therapies, including the 10.8mg formulation where clinically appropriate, could be undertaken safely.
