Q&A: Generic imatinib
(From CML News October 2016 issue)
In October 2016, generic imatinib became available in Australia.
As the patent to the original imatinib (called Glivec®) ends, new brands of the drug will enter the market. These new brands of imatinib will be much cheaper, saving the Pharmaceutical Benefits Scheme (PBS) millions of dollars.
In the coming months, your doctor may choose to ask if you would like to change from your current brand of imatinib, to a different, cheaper brand.
Some people may feel hesitant about changing their medication, which has been holding their disease at bay. Dr David Yeung, haematologist at Royal Adelaide Hospital and CML Research Fellow at South Australian Health & Medical Research Institute, answers the questions you may be asking about what this means.
Q. What is meant by the term ‘generic’ imatinib?
Novartis – the company that originally developed imatinib as a successful treatment for CML – has had sole rights to manufacture and distribute imatinib under the brand name Glivec®, under patent protection. That patent has expired in Australia. This means other pharmaceutical companies now can legally make and distribute imatinib tablets but under different brand names, as Glivec remains a trademark of Novartis. Generic imatinib is expected to be significantly cheaper than the originally branded Glivec. To market a generic drug, manufacturers must demonstrate that their drugs are identical to the original branded drug in terms of dosage form, safety, strength, route of administration, quality, performance characteristics, and intended use. For more information, click here.
Q. Is generic imatinib a lower quality medicine to Glivec?
The Therapeutic Goods Administration (TGA) license and set standards for medicines in Australia. We (Australian doctors) have confidence in the TGA in its role ensuring that medicines available in Australia are efficacious and made to acceptable standards, regardless of the manufacturer. The TGA will ensure all imatinib distributed in Australia, regardless of whether it is generic imatinib or Glivec, will be safe and effective. We believe all imatinib tablets sold here will have the same active imatinib ingredient, and at the same doses, regardless of manufacturer. Generic versions of a number of drugs already are sold in Australia, such as anti-hypertensives and cholesterol lowering agents, and studies have established that generic versions of these drugs, used in cardiovascular disease, lead to the same results as the original brands. Generic imatinib is already available in other countries, including New Zealand and Canada.
Q. How is generic imatinib different to Glivec?
Several companies are expected to manufacture generic imatinib. They will have different brand names and the shape, size and colour of the tablets are likely to be different too. However, each tablet will have the standard quantity of the active compound, imatinib. Apart from the active compound, tablets usually contain ingredients that are added to the tablets to stabilise the active compound, and to add colour and shape. These inactive ingredients may vary between different products made by different companies. We do not expect patients to have different side-effects when and if they switch to generic forms of imatinib, unless they have a reaction to one of the inactive ingredients.
Q. Why is the Pharmaceutical Benefits Scheme changing our access to Glivec/imatinib?
Novartis’ patent on Glivec in Australia has expired, allowing other manufacturers the opportunity to make and market imatinib. The TGA will license these generic drugs and the PBS will provide them to Australian patients. These generic drugs will provide large cost savings to the Government over time.
Q. Do I have to go on generic imatinib and can I choose to stay on Glivec?
In Australia, patients and doctors can choose the manufacturer of their medicine. This includes the choice to choose Glivec. In some cases, there may be a cost difference to the patient if the premium brand is dispensed, compared to the generic. However, the cost of a month’s supply of imatinib will not exceed $38.30 (or $6.20 for concession card holders), as at 2016.
Patients can also choose between different brands/manufacturers of generic imatinib. However, pharmacies may only stock drugs from one or two manufacturers, and non-generic forms may not be available at certain pharmacies. At this stage, it is not clear how many brands of imatinib, including Glivec, will be available to Australian patients.
Q. What are the benefits of going on generic imatinib?
Generic imatinib is likely to cost less for the PBS system to purchase. This will lower the Federal government’s cost of providing care to CML patients in Australia, making our health system more cost effective. At the same time, treatment outcomes will not be compromised.
Q. Should I take extra precautions if I do switch to generic imatinib?
The usual precautions you take when having Glivec apply. Take tablets at the same dose, around the same time each day, with a substantial meal.
Q. Will I need more frequent follow-up with my doctor for a time to ensure my CML remains under control?
For patients already established as having a stable molecular response, we do not expect extra monitoring to be necessary. However, in some cases where treatment response is not as well established, extra monitoring may be necessary. Your haematologist will work this out with you.
Q. Some people fear losing their response to CML if they begin treatment with generic imatinib. How likely is this to occur?
Patients with no new side-effects and who are taking their pills as directed will not lose their treatment response. This will apply to the majority of patients who decide to use generic imatinib.
Q. Would generic imatinib be recommended for everyone or are there some patients who should remain on Glivec?
The very occasional patient may have new side-effects when switching to generic imatinib. This is likely to be due to changes in formulation and in particular, to the inactive ingredients. If this occurs, going back to Glivec may solve the problem.
Q. Will switching to generic imatinib affect my ability to enter an imatinib cessation trial in the future?