BBreast cancer patients are very insecure: There are massive supply bottlenecks for the drug tamoxifen, which tens of thousands have been taking for years. “Our inbox is full of concerned inquiries,” reports Andrea Hahne from the BRCA network, which advises women with breast cancer. “They are worried that the cancer will come back if the therapy is not continued.” Gynecologists and oncologists are vehemently demanding that more supplies come soon, but also say: There is no reason to panic.
Tamoxifen is what is known as a selective estrogen receptor modulator. These are medicines that mediate their effect through the receptors for the hormone estrogen. The active ingredient docks onto the tumor cell and blocks the influence of estrogen on the growth of the tumor cell. In this way, it ensures that tumor cells do not continue to grow.
Tamoxifen is used in aftercare – the aim is to reduce the likelihood of a relapse in the long term. “It is an indispensable part of the therapy of patients with hormone receptor-positive breast cancer,” says a statement with which five specialist societies reacted to the situation.
The corona pandemic is also to blame for the lack of supply
Those affected usually take 20 milligrams a day – for five to ten years. According to the GKV drug index, 27 to 28 million daily doses were prescribed in the years 2019 to 2021. This is based on estimates that 120,000 to 130,000 female patients – but also some male patients – could be affected by the tamoxifen bottleneck.
“The causes of this lack of supply are manifold,” says the Federal Institute for Drugs and Medical Devices (BfArM): There is no single cause, but “interactions of different effects”.
The professional societies see a possible explanation, among other things, in an “increase in prescriptions since the first quarter of 2020 in connection with the lockdown measures due to the Covid 19 pandemic”.
It is conceivable that women stocked up at the beginning of the corona pandemic. The BfArM has been monitoring the development since January. Because the market share of tamoxifen is high, it is one of the “supply-relevant active ingredients”. The Advisory Board for Delivery and Supply Bottlenecks at the BfArM has introduced measures to alleviate the supply bottleneck.
“No prescriptions for individual storage”
The companies should check whether contingents “can be made available for the German market without creating a supply shortage in other countries”. Doctors should “not issue prescriptions for individual stocking” in the coming months. Patients should switch to other pack sizes, for example take 10 milligrams twice instead of the usual 20 milligram tablet.
The question remains what those affected should do if supplies come to a complete standstill. “An alternative equivalent drug therapy is not available,” says the official announcement by the Federal Ministry of Health in the Federal Gazette on February 18th. “But there are alternatives,” says Michael Untch, head of gynecology at the Helios Clinic in Berlin-Buch: Nobody should be afraid.
So-called aromatase inhibitors and hormone-inhibiting injections are available as alternatives. These are drugs that block estrogen production. The problem: “Replacing tamoxifen with other forms of endocrine therapy is associated with a higher rate of side effects,” warn the professional societies.
Above all, bone problems from joint pain to osteoporosis are mentioned. You can get the side effects under control, says Untch. “The most important message is: An alternative therapy must be found.” Interrupting the therapy could increase the relapse rate.
Changing the preparation depends on the individual case
Whether it makes sense to change the drug at short notice to bridge the bottleneck depends on the individual case, says Bernhard Wörmann from the Clinic for Haematology, Oncology and Tumor Immunology at the Berlin Charité. A short-term interruption of a few days is also medically possible. However, he emphasizes: “The interruption of therapy is not a solution to this supply crisis.”
It is not yet clear how long the bottleneck will last. “The complex and time-consuming manufacturing process of drugs with the active ingredient tamoxifen requires a lead time of several weeks,” explains the BfArM. Replenishment could be expected “around the end of April 2022”. The first imported batches could possibly arrive as early as next week, says Wörmann.
In any case, consultant Hahne is “stunned that such a banal active substance that has been tried and tested for a long time is not available”. In order to avoid bottlenecks in the future, Wörmann calls for forward-looking purchasing in the future: “We need a six-month stockpile for such indispensable preparations.”