番茄社区

CHICAGO -- A sublingual vaccine not only reduced the risk of recurrent urinary tract infections (UTIs) in women, it also appeared to enable a significant number of these women to be completely UTI-free, according to a North American study.

Among 67 women with three or more UTIs per year, 40.6% of those receiving a 3-month course of the MV140 vaccine had no UTIs during the 9-month post-vaccination study period, reported J. Curtis Nickel, MD, of Queen's University in Kingston, Ontario, at the American Urological Association annual meeting.

Compared with the UTI rate in the year prior to vaccination (0.56 UTIs per patient per month), the reduction in UTI rate was 75.3% for the 9-month efficacy period (0.14 UTIs per patient per month).

Nickel and colleagues also reported that the total number of UTIs and patients reporting UTIs decreased substantially for each 3-month follow-up period, while the percentage of UTI-free patients increased following vaccination.

At the 12-month efficacy visit, 82% of study participants reported that they were moderately/markedly improved, and 59% were mostly satisfied, pleased, or delighted.

There were 14 adverse reactions that were potentially related to the vaccine in nine patients, all of which were mild and resolved by 3 months. No patients needed to withdraw from the study due to an adverse reaction.

"We think this is going to have a major impact when approved for patients with recurrent urinary tract infections, and I'm thinking in women with uncomplicated, recurrent urinary tract infections," Nickel said in a press briefing.

Wai Lee, MD, of Northwell Health's North Shore University Hospital and Long Island Jewish Medical Center in Manhasset, New York, who moderated the press briefing, noted that "the challenges of treating patients with urinary tract infections are that some patients have very, very difficult-to-treat conditions. We try a lot of different modalities and it can be frustrating -- especially for the patient -- and to have another option for patients is really powerful."

European Study Confirmed

"We all understand that urinary tract infections are major problems," said Nickel, in explaining the rationale behind the development of the vaccine. "They can be treated with antibiotics, but the impact of long-term antibiotics to prevent urinary tract infections has a deleterious effect on patients and society in terms of side effects, causes, and the rising spectra of bacterial resistance."

MV140 is a sublingual preparation of whole-cell inactivated bacteria. Nickel noted that the vaccine was previously evaluated in a 1-year trial of 240 women from Spain and the U.K. In that trial, the results of which were published in , women were randomized to MV140 for 3 or 6 months or placebo for 6 months in a 1:1:1 ratio.

The primary endpoint was the number of UTIs in the 9-month period after 3 months of intervention. Study authors, who included Nickel, found that among women treated with placebo, 25% were free of UTIs, compared with 56% and 58% of those who received 3 and 6 months of MV140, respectively.

"It showed that this vaccine was very successful and safe," Nickel said. "But there's no North American clinical or research experience with this vaccine. So, before it could be approved by Health Canada, we had to see some real-world evidence that it would work in North American women, prescribed by North American physicians."

The North American trial included 67 women, 64 of whom completed the 3-month vaccination period and were followed for 9 months. Patients had a mean age of 55.6 years and a mean of 6.2 UTIs per year, with Escherichia coli (59%), Klebsiella (18%), and Enterococcus (15%) being the predominant causative bacterial species.

When asked who should be treated if this vaccine were more broadly used, Nickel said that at this point it has been shown to work in women with uncomplicated UTIs, but that he would not advocate using it in men, children, or complicated UTIs.

"We just don't have the data," he said. "All those three studies are planned now, and when the results of those studies are available, and if they prove that there is efficacy in those populations, then by all means that vaccine can, and should be, used in those populations."

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