Currently, using an inhaler is the most common way of treating asthma. Inhalers contain medicines that relax and open the airways and reduce swelling to allow air to enter the lungs more easily. For the majority of people, using inhalers (or “puffers”) keeps their asthma under control and allows them to live a healthy and active life. Some people have severe asthma, which is a type of asthma that is hard to control even using high doses of standard asthma medicines. For these people, a different medication is required.

A relatively new way to treat severe asthma is to use a class of drugs called biologics. Biologics are medicines that contain substances that have been isolated from a natural source. This source includes: human cells, microorganisms, plants or animals. Apart from asthma, biologics have been developed to treat many different diseases, including: cancer, rheumatoid arthritis and psoriasis.


The biologics that have been approved to treat severe asthma in New Zealand are called omalizumab (brand name: Xolair), mepolizumab (brand name: Nucala) and more recently benralizumab (Fasenra). Omalizumab is used to treat severe allergic asthma, whereas mepolizumab and benralizumab are used to treat people with severe eosinophilic asthma: a type of asthma caused by high numbers of white blood cells that cause swelling and inflammation in the lungs. All these medications omalizumab, mepolizumab and benralizumab work by recognising and blocking substances in the lungs that cause lung inflammation and asthma symptoms.

Biologics are administered by regular injection every four to eight weeks, depending on the biological medicine used, your weight and asthma severity. Injections can be given by healthcare providers in a healthcare setting or self-administered at home if your healthcare practitioner deems it safe. For some people, who struggle to remember to take their inhaler daily, an injection every month or two is a huge benefit of biologics’ treatment. However, most people still need to take their inhalers as well as having the injections.

Perhaps the main benefit however, is that treatment with biologics can improve the quality of life of people with severe asthma and reduce the frequency of asthma flare-ups and hospitalisation. Biologics also replace the need for high doses of corticosteroids, which can cause unpleasant side effects.

The number of people eligible for treatment with biologics is relatively small; only people with specific types of severe asthma that cannot be controlled with high doses of corticosteroids can be prescribed omalizumab, mepolizumab, and benralizumab in New Zealand. In order to be prescribed biologics for asthma, your healthcare practitioner will refer you to a respiratory specialist or a clinical immunologist, who will run tests to determine if you are eligible for biologic treatment.

As asthma is one of the most common chronic diseases across the globe, research in to the condition continues to be relatively well-funded globally. In the future, we hope to see more biologics and other medicines on the market to further improve the quality of life for people with asthma.

Severe asthma

People with severe asthma have persistent symptoms including: constant breathlessness, continuous cough, difficulty speaking in full sentences and a heavy feeling in the chest. As these symptoms cannot be alleviated by taking standard medication from a reliever inhaler, instead people with severe asthma are often given higher doses of medication and longer-lasting medication in order to keep the airways open for extended periods of time. Antibiotics are also used for people with severe asthma. Often, people with asthma mistakenly assume they have severe asthma because they experience lots of bad asthma symptoms. However, it is most likely that their asthma is just not well controlled. If this is the case, their healthcare practitioner can alter their treatment regimen and the patient will feel better as they regain good control of their asthma.

If changing a treatment regimen doesn’t improve symptoms, a patient will be referred to specialist asthma care where they may receive a diagnosis of severe asthma. A variety of tests are used to diagnose severe asthma, including: lung volume tests, spirometry, imaging scans and gas transfer tests. A severe asthma diagnosis may sound scary but it will allow a patient to gain access to the help and support needed to manage their condition properly.

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