A medicine licensed to treat psoriasis worsened symptoms in patients with severe asthma, according to trial results published today in the New England Journal of Medicine.

The study, which was led by researchers at the National Institute for Health Research (NIHR) Leicester Biomedical Research Centrea partnership between Leicester's Hospitals, the University of Leicester and Loughborough University investigated whether risankizumab could potentially improve the symptoms and reduce 'attacks' in people with severe asthma.

The international study, co-led by researchers in Manchester, Belgium and Canada, recruited 214 patients into the trial; 105 patients were randomised to a risankizumab injection every four weeks over a 24-week period, while 109 patients received a placebo.

Researchers measured the 'time-to-first' worsening determined by increasing symptoms, deterioration in breathing tests, increased use of inhalers and need for steroid tablets. Patients treated with risankizumab had an average time-to-first-worsening of 40 days, compared to 86 days for the patients given a placebo. Studying 'gene signatures' from immune cells in airway samples, risankizumab was shown to decrease molecules known to be important in protection against infection, which possibly explains the observed poorer asthma control.

Professor Chris Brightling, NIHR Senior Investigator at the NIHR Leicester Biomedical Research Centre (BRC) and study lead, said: "It is always disappointing when a potential treatment is shown to be ineffective at treating a disease, more so when it makes symptoms worse.

"We think risankizumab reduces the presence of substances in the airways that are important factors in preventing infections, which probably makes the patients' symptoms worse. This theory is backed by molecular profiling, which shows reduced levels of these substances in samples taken from patients on the trial."

The study, which was sponsored by AbbVie and Boehringer Ingelheim is registered on ClinicalTrials.gov, NCT02443298. It was also part-funded by 3TR-Innovative Medicines Initiative (IMI), a consortium of academic institutions, charities and industry partners that aims to provide fundamental new insights into the molecular pathways and mechanisms of response and non-response to treatment for autoimmune, inflammatory and allergic diseases.

The paper "Risankizumab in Severe Asthma: A Phase IIa, Placebo-Controlled Study" is published in the New England Journal of Medicine, today (28 October 2021).