Real World Bezlotoxumab Use for Recurrent C diff

March 31, 2020

After the MODIFY trial, investigators wanted to explore how bezlotoxumab treated patients in the real world.

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.”