Oral vaccine prevents recurring UTIs for nine years

A new oral vaccine helped prevent recurring urinary tract infections (UTIs) for nearly a decade. A clinical trial showed that the pineapple-flavoured vaccine spray helped 53.9 per cent of people remain UTI-free for nine years.

UTIs are among the most common bladder infections, and they disproportionately affect women. About 40 to 60 per cent of women experience a UTI at least once in their life, and one in four are prone to repeat infections. Urinary tract infections are often treated with antibiotics. However, this incurs the risk of antibiotic resistance, making these drugs less effective with repeated use.

As an alternative, researchers developed the MV140 vaccine, which contains four inactivated bacterial species that cause UTIs. The dissolved vaccine, sprayed under the tongue daily for three months, passes through the soft mucous membrane inside the mouth to stimulate lymphoid tissues, a component of the immune system.

The latest clinical trial, presented on 6 April at the European Association of Urology Congress in Paris, is the first to show the long-term effectiveness of the MV140 vaccine. The study authors previously reported the short-term effectiveness of the vaccine after three and six months. The researchers tracked the medical records and regularly followed up on 89 participants who received the vaccine in 2014. All participants had a history of UTIs but were UTI-free during the three-month vaccination period.

After they completed treatment with the spray, people remained infection-free for an average time of 54.7 months. More than half of the group – 54 per cent of the women and 53 per cent of the men – avoided UTIs for nine years.

“People who caught UTIs had a milder form and only drank lots of water and felt fine,” says Bob Yang at the Royal Berkshire Hospital in the UK, a coauthor of the study.

One concern, however, is the study size. S. Adam Ramin at Urology Cancer Specialists in California points out that about half of women will develop a UTI over the course of a lifetime. In comparison, only 54 per cent of the women who received the vaccine avoided UTIs for the entire nine-year study period. This “falls within the range of insignificant difference in such [a] small sample population,” he says.

Previously, another group attempted to make a UTI vaccine in tablet form. But Yang says one appeal of using a spray is that people are more likely to take it. “It’s not a tablet but a spray underneath the tongue that helps with compliance,” explains Yang. He says the taste of pineapple helps people forget they are taking medicine, and the spray is easier for older adults who have trouble swallowing medicine.