Real World Bezlotoxumab Use for Recurrent C diff

Bezlotoxumab use can prevent recurrent Clostridioides difficile (C diff) infection in the real world, according to a paper published in Open Forum Infectious Diseases.

Investigators from all over the United States retrospectively studied 200 patients across 34 centers in order to assess recurrent C diff infection after 90-days post treatment with bezlotoxumab. The patients were treated with bezlotoxumab between April 2017 and December 2018. The antibody bezlotoxumab was approved for the prevention of recurrent C diff in adult patients receiving standard care antibiotic therapy and who are at high risk for recurrence. Previous studies showed bezlotoxumab had significantly lower rates of recurrent C diff and was especially effective in patients with more than 1 risk factor for recurrent C diff, the study authors wrote.

The adult patients had a median age of 70 years and two-thirds of the cohort was female. A majority of the patients had prior C diff episodes (86%). Most of the patients had 2 or more risk factors for recurrent C diff (79%), including age greater than 65 years, history of C diff in the previous 6 months, compromised immunity, severe C diff infection, and having a strain associated with poor C diff outcomes.

Prior to bezlotoxumab treatment, the standard of care antibiotics administered to the patients included fixed dose vancomycin (38%), tapered vancomycin (30%), fidaxomicin (30%), and metronidazole (1.5%). These were done in combination with bezlotoxumab, which was administered to those patients as a single intravenous infusion over 60 minutes, the investigators said.

Within 90 days, 31 patients (16%) experienced recurrent C diff, the study authors found. They extrapolated this data to correspond to a success rate of 84%.

After treatment with bezlotoxumab, 17 of those patients were treated with standard antibiotics, 12 were treated with standard antibiotics plus fecal microbiota transplant (FMT), and 2 were treated with FMT only. Hospitalization due to recurrent C diff was observed in 11 of those 31 patients and 3 were admitted with severe disease.

The median time to C diff recurrence was 31 days, but ranged from 5 to 76 days. Half of the patients saw recurrent C diff within 30 days, 14 patients between 30-60 days, and 2 between 60-90 days post- bezlotoxumab.

The study authors also found that patients with 2 or more C diff recurrences before treatment with bezlotoxumab were independently associated with a higher risk for subsequent C diff recurrence compared to those with just 1 recurrence or primary C diff infection.

There were no infusion-related reactions for bezlotoxumab treatment, the study authors found. There were 2 deaths reported; 1 died a week post-bezlotoxumab but had a history of worsening interstitial lung disease, and another died 40 days post-bezlotoxumab but had systemic lupus, end stage renal disease, and 6 prior C diff episodes.

“Bezlotoxumab has been shown to effectively reduce the risk of recurrent C diff infection in the pivotal MODIFY trials,” the study authors concluded. “Our findings indicate that a single infusion of bezlotoxumab resulted in a CDI recurrence rate of 15.9%, which is comparable to 16.5% reported for the overall population enrolled in the MODIFY trials.”