What’s new in the world of diabetes medicationsFriday, 18 December 2020
Almost all medications or products for which therapeutic claims are made must be entered in the Australian Register of Therapeutic Goods (ARTG) before it can be supplied in Australia. The Australian Therapeutic Goods Administration (TGA) carry out a range of assessment and monitoring activities to ensure therapeutic goods, such as continuous glucose monitoring (CGM) systems or insulin pumps available in Australia are of an acceptable standard. The TGA generally has it as a pre-requisite that products are approved by the US Food and Drug Administration (FDA), or their European counterpart the European Medicines Agency (EMA), before testing can commence in Australia.
New medications are slow to come through as it is costly to develop and market them. According to the Tufts Centre for the Study of Drug Development, the cost of bringing a new drug from its conception to shelves was about $320 million in the 1990s. By 2017 it had risen to around $2.7 billion. These high costs and uncertainty regarding return on investments limits investments by pharmaceutical companies in the development of new medications for diabetes.
New medications – insulin
Afrezza is a man-made, inhaled, rapid-acting insulin with a very fast onset (the time it takes for insulin to start working) and fast offset (the time it takes for insulin to finish working). Its blood-glucose-lowering action peaks just 12 minutes after inhaling, compared to over 30 minutes for typical rapid-acting mealtime insulins such as Novorapid, Humalog and Apidra. It is generally used in conjunction with long-acting insulin, but it is not recommended in people who smoke or have recently stopped smoking. Afrezza is currently available only in the US and for adults only.
A biosimilar medicine is a highly similar version of a reference biological medicine. The processes that produce biological and biosimilar medicines are naturally variable as they come from living cells; this means that no two batches are ever exactly the same. Biosimilar medicines have been tested and proven to be as safe and effective as the reference biological medicine.
Lantus is a biological medication that has been used successfully for many years. However, Lantus Solostar and Lantus insulin glargine 100 IU/mL products were removed from the Australian market from 1 July 2020. If you are using either of these products you will need to change to another insulin glargine injection.
There are currently two options:
Optisulin is the same formulation as Lantus and is available in two delivery methods: a prefilled disposable injector pen (Optisulin Solostar) and cartridges for use in reusable injector pens (AllStar, AllStar Pro, JuniorStar or ClikStar).
Semglee is a biosimilar insulin Glargine U-100 which is only available in pre-filled disposable pens. It has been listed and marked as “equivalent for the purposes of substitution for Lantus” on the PBS since 1 October 2019. Talk to your doctor before changing from Lantus to Semglee as these two insulins are similar, but not exactly the same.
Fiasp is a variation of insulin aspart, better known as Novorapid, but is absorbed faster as it has niacinamide (vitamin B3) and arginine (an amino acid) added. Fiasp has a faster onset and faster, higher peak than Novorapid and thereby provides quicker insulin cover at meals, while the duration of action is similar to Novorapid. This means that Fiasp allows you to delay injectioning until the first bite of your meal or within 20 minutes of starting a meal, allowing you to decide how much you are going to eat and dose accordingly. Fiasp has been on the PBS for about one year, it is available at the same cost as other rapid acting insulins.
Ryzodeg® 70/30 has been available on the PBS since August 2018, but we thought it is worth a mention here anyway. Ryzodeg 70/30 contains two types of insulin: a basal (or background) insulin called insulin degludec and rapid acting insulin called insulin aspart (more commonly known as Novorapid). Compared to other basal insulins (such as insulin detemir (Levemir) which lasts around 20 hours or insulin glargine (see above) which works for up to 24 hours), Degludec has a duration of action beyond 42 hours and this means that there is less variation in your blood glucose levels from one day to the next, even if you vary the timing of your injections.
Tresiba is a single ingredient insulin degludec and has been available in the UK and US since 2015. The Australian TGA approved it for use by adults at the same time as Ryzodeg in November 2017; however, Tresiba is not yet subsidised by the PBS.
New medications – other injectables: GLP-1
Glucagon-like peptide-1 (GLP-1) receptor agonists work by stimulating the release of insulin by the pancreas after eating, even before the blood glucose levels start to rise. At the same time GLP-1 inhibits the release of glucagon by the pancreas, which slows down the release of stored glucose from the liver. Thirdly, GLP-1 slows the absorption of glucose into the blood stream, by slowing stomach emptying; this makes you feel fuller for longer.
The chemical structure of GLP-1 and duration of action is different for different brands. There are several GLP-1 receptor agonists available to people with type 2 diabetes, though only four of them are currently available in Australia, three of which are on the PBS. GLP-1 is mostly an injectable medication (but it is not insulin) that generally comes in a pre-filled, multi-dose, disposable injection pen device.
- Dulaglutide, known in Australia as Trulicity, is a once weekly GLP-1 available on the PBS with an authority prescription.
- Exenatide comes in two formulations. Byetta, a twice daily injection and Bydureon, a once weekly injection. Both are available on the PBS.
- Liraglutide is known as either Vyctoza or Saxenda; both are available in Australia, but on a private script only. Vyctoza is used to treat type 2 diabetes, whereas Saxenda is marketed for people who do not have diabetes but who are overweight or obese.
- Lixisenatide or Lyxumia was registered with the TGA in 2013 but is not yet available on the PBS.
- Semaglutide is marketed as Ozempic and is another once weekly GLP-1. It was approved for listing on the PBS in November 2019.
There are two honourable mentions for other GLP-1 preparations:
Rybelsus is the first pill in the class of drugs called ‘glucagon-like peptide’ approved for use in the US. The generic name is semaglutide. However, it appears that this medication has some significant risks as recent studies have shown that it may cause certain thyroid tumours and can cause inflammation of the pancreas, kidney injury, vision loss and hypoglycaemia (low blood glucose levels) and so it remains to be seen if it ever makes it into Australia.
The makers of Optisulin (formerly known as Lantus, insulin Glargine U-100) have created a two-in-one medication which includes both insulin Glargine and Lixisenatide. Sanofi has submitted an application with the PBS for this medication to be available on the Australian market.
New medications – tablets
In the last 12 months we have seen the addition of a new sodium-glucose co-transporter-2 (SGLT-2) inhibitor called Steglatro (Ertugliflozin) added to the list of PBS medications. SGLT-2 inhibitors help lower blood glucose levels in people with type 2 diabetes by removing glucose from the body through the urine. Other SGLT-2 medications available in Australia include dapagliflozin (Forxiga) and empagliflozin (Jardiance).
Steglujan is a combination medication of the aforementioned SGLT-2 inhibitor ertugliflozin and a dipeptidyl peptidase-4 inhibitor (DPP4-inhibitor) sitagliptin (also known as Januvia).
Segluromet also has two active drugs, they are the SGLT-2 inhibitor ertugliflozin and metformin (also known as Diabex or Diaformin), which is a common medication and belongs to a group of medications called biguanides.
Trijardy XR is the first triple-combination medication that has been approved by the FDA; it contains empagliflozin (Jardiance), linagliptin (Trajenta), and extended-release metformin hydrochloride (Diabex XR or Diaformin XR). Although it has FDA approval, it is yet to make its way across to Australia.
If you think you would benefit from any of the products or medications mentioned in this article, please talk to your healthcare provider for further advice.