New Drug Offers Hope for Kiwis Living With Rare Disorder
New Zealanders living with a rare blood disorder which can cause spontaneous, fatal internal bleeding and excruciating arthritis-like symptoms are set to benefit from the Medsafe registration of a new medicine.
Haemophilia A is an inherited blood disorder caused by lack of a clotting protein called factor VIII, it affects eight in every 100,000 Kiwis, with males most likely to be diagnosed with the condition.
The approval of the medicine is significant as it is the first new treatment for those living with this disease who show an immunological rejection of factor VIII to be made available in New Zealand in the past 20 years.
According to Senior Lecturer at Otago University and Consultant Haematologist Dr Mark Smith there are around 800 Kiwis living with haemophilia and around 365 have a severe form of the condition called Haemophilia A which puts them at extreme risk of spontaneous internal bleeding.
“The bleeding will often pool around the joints which can cause significant levels of pain - in the past this was often treated with morphine which severely impacted the ability to function and led to time off work or school,” he says.
People with haemophilia A are usually treated with factor VIII medicines, which replace the missing factor VIII and help control and prevent bleeding. However, the body may develop inhibitors (antibodies) as a reaction to these medicines in around 25-30% of the cases. The inhibitors reduce the medicines’ effect, so bleeding is no longer controlled.
A new medicine, Hemlibra (emicizumab), which gained priority registration from Medsafe today, works by mimicking the coagulation function of activated factor VIII and can prevent or reduce the frequency of bleeding episodes in adults and children with hemophilia A with factor VIII inhibitors.
The treatment is given weekly via a subcutaneous injection, which means it can be injected under the skin without the inconvenience of needing to locate a vein.
Dr Smith says haemophilia can have a significant impact on the quality of life for those living with the condition as well as their families.
“Haemophilia is often picked up at birth, the baby may be born with unusually severe bruising and then tested as a result.
He says one of the current treatments for children with the disease may involve regular intravenous injections every couple of days - with infusions taking 20 minutes each time.
“Younger children might need to have ports surgically implanted in their body - in their chest through which the factor replacement is infused; these can get infected leading to long periods of antibiotic treatment and often port removal,” he says.
Dr Smith says one of the key goals in treating those living with haemophilia is to prevent damage to joints which is caused by blood pooling in this part of the body.
“Young New Zealanders with haemophilia need to stay on top of the bleeds and work hard to avoid damage to their joints so that when they’re in their early twenties, they're not having to have a joint replacement or a joint fusion.
“For older people we need to ensure we are supporting them in the right way and enabling them to have the right treatment packages including joint replacements to minimise further bleeding,” he says .
Dr Smith says new scientific advancements are helping extend the life expectancy of those living with haemophilia.
“Five decades ago, someone living with severe haemophilia may have lived to be 25, now with new treatments they can have a normal lifespan, which is why we need to continue to support advances in scientific research in this field,” he says.
“I am passionate about clinical trials and I would like to see more patients given the opportunity to take part in them. I always try and explain to patients the science and make it less complicated for them, because a well-run study will ultimately result in an improved medicine being made available,” he says.
Dr Smith says along with more convenient treatment options, he would like to see better access to specialists and physiotherapists throughout the country, and more testing for those women who may be carriers.
“I would like to see a system that would allow faster access to care for women who carry the gene, treatment for those who live in the regions can be challenging, and our aim is to have medicine in their home, sitting in their fridge - to allow for the immediate treatment of bleeds,” he says.
Roche NZ General Manager Ian Black says the company is proud to have developed Hemlibra and is excited to be able to provide this treatment option to Kiwis who live with haemophilia A with inhibitors.
Black says data from one of the largest global studies among people with hemophilia A found an 87 percent reduction in treated bleeds in people who received the new drug as part of their treatment regime.
He says current treatment alternatives in people with haemophilia A who develop inhibitors are time-consuming and often difficult, especially for children and are not always effective. He says there was an unmet medical need for more convenient and effective treatment options.
Black says while the therapy is approved to treat those with the condition who have inhibitors, more research has recently been completed which investigated the potential for the drug to treat haemophilia A without inhibitors.