Painful treatment for rheumatic heart disease might be on course for change with an international trial showing 95 per cent of patients preferred penicillin injections into abdominal tissue under the skin, reporting it was less painful than traditional treatment.
Rheumatic heart disease (RHD) – caused by invasive Strep A bacteria that scars the heart and can lead to heart failure – disproportionately affects First Nations, Torres Strait Islander, Māori and Pacific populations, claiming 400,000 lives each year globally.
Treatment traditionally requires intramuscular injections of thick penicillin, likened to the texture of toothpaste, in the buttocks causing pain – one factor discouraging patients returning for monthly treatments.
Barriers like pain and treatment frequency, led an international team of researchers to investigate new ways to treat RHD, to remove barriers and provide patients with more treatment options.
Researchers from New Zealand and Australia trialled an alternative treatment on 50 participants in North Island in New Zealand; an area where Māori and Pacific people are over-burdened with RHD.
The Otago University-led study, published in the PLOS One journal, found patients overwhelmingly preferred abdominal injections, with reduced pain a key feature of their experience.
The trial was informed by an earlier trial undertaken in Perth – coined the subcutaneous injection of benzathine penicillin G or SCIP – which tested the alternative treatment on 24 healthy adults, who tolerated it well.
The SCIP trial also found larger doses could be given in one visit, extending treatment cycles to around every three months.
Co-author Associate Professor Laurens Manning, from the Wesfarmers Centre of Vaccines and Infectious Diseases at The Kids Research Institute Australia and The University of Western Australia’s Medical School, said both studies’ results were promising, removing barriers while providing patients with a menu of options.
“The New Zealand and Perth trials of SCIP both have showed promise for patients in terms of pain reduction and frequency of injections, the two major barriers for continued treatment,” Associate Professor Manning said.
“We’re now in the process of identifying sites to conduct more community-led trials in the Northern Territory and Western Australia with First Nations people, who have said in discussions they’re excited about the results of the New Zealand study.
“These studies are community-led to ensure the patient experience is a core focus in managing RHD to improve cardiovascular inequality.”
Lead author Dr Julie Bennett from Otago University, said results represented a potential leap forward in disease management, where a 70-year-old painful method could potentially be phased out.
“This new method shows enormous promise as an alternative mode of penicillin delivery and may increase adherence through improved patient experience,” says Dr Bennett.
“Greater adherence may prevent disease progression and death here in New Zealand and globally.”
The subcutaneous injection might also work in different areas of the body where penicillin can be infused into fatty tissue, yet at this stage researchers are focusing on the abdominal area.
Researchers will now continue clinical trials using the SCIP method to gather more data to eventually change the therapeutic landscape.
The article “Hurts less, lasts longer”: a qualitative study on experiences of young people receiving high-dose subcutaneous injections of benzathine penicillin G to prevent rheumatic heart disease in New Zealand is available here.