Bezlotoxumab for Prevention of Recurrent Clostridium difficile Infection in Cancer Patients: Report of Clinical Case

Clostridium difficile infection is a leading cause of healthcare-associated morbidity, especially in immunocompromised hosts such as cancer patients. Recurrent CDI complicates treatment outcomes and quality of life, and increases healthcare costs. Cancer patients face unique challenges—immunosuppression, chemotherapy, frequent hospitalizations, and antibiotic use all contribute to increased incidence and severity of CDI. Standard-of-care antibiotics (vancomycin, fidaxomicin) are effective for initial cure but provide limited protection against recurrence. Bezlotoxumab has emerged as an adjunctive preventive option against rCDI, particularly in high-risk cohorts. This article presents a detailed case report and a review of existing evidence for bezlotoxumab's role in cancer patients.

Patient Background

·        Demographics: 60-year-old woman

·        Diagnosis: Metastatic breast cancer, on palliative chemotherapy (docetaxel and carboplatin)

·        Medical History: Multiple prior hospitalizations, two documented episodes of CDI in the past eight months, recurrent neutropenia, recent course of piperacillin-tazobactam for febrile neutropenia

Clinical Course

1.      Presentation: Admitted with new-onset watery diarrhea (≥5 stools/day), abdominal cramps, and low-grade fever.

2.      Workup:

o   Positive for C. difficile toxin B gene (PCR).

o   Laboratory: Neutropenia (ANC 900/μL), mild renal insufficiency.

o   Imaging: No toxic megacolon.

3.      Management:

o   Standard-of-care: Oral vancomycin 125mg q6h initiated.

o   Supportive care: Intravenous fluids, neutropenic precautions.

o   Gastroenterology consult recommended adjunctive bezlotoxumab due to multiple recurrences and cancer status.

o   Bezlotoxumab 10mg/kg single intravenous infusion administered on day 3 of vancomycin therapy.

4.      Course and Outcomes:

o   Diarrhea resolved within five days.

o   ANC recovery by day 7; discharged off antibiotics.

o   No recurrence of CDI over 12-week follow-up despite ongoing chemotherapy and subsequent courses of prophylactic antibiotics.

o   No infusion reactions or bezlotoxumab-related adverse events documented.

Table 1. Timeline of Clinical Events

Efficacy in Cancer Patients

·        Post-hoc analysis of MODFIY I/II trials: 382 cancer patients analyzed (190 bezlotoxumab, 192 placebo). Recurrent CDI rates were significantly lower in the bezlotoxumab arm (17.8%) vs. placebo (30.4%); absolute risk reduction 12.6% (95% CI: –22.5% to –2.7%) ^[1][2][3].

·        Initial clinical cure rates were similar between treatment groups, indicating bezlotoxumab's role is prevention, not acute treatment ^[1][3].

·        Hospital readmissions and mortality: Trends for fewer 30-day CDI-associated rehospitalizations and lower 90-day mortality observed in bezlotoxumab-treated cancer patients (not statistically significant) ^[2].

Mechanism & Rationale

·        Bezlotoxumab binds and neutralizes C. difficile toxin B, the principal driver of colonic inflammation and recurrence.

·        Lack of immunogenicity makes it particularly suited for immunocompromised hosts such as cancer patients, who often fail to mount an effective antibody response to toxins after CDI ^[4][5].

Safety

·        Comparable infusion-related reactions and adverse event rates across studies for cancer and non-cancer cohorts.

·        No new safety signals observed in post-hoc analyses or real-world studies for the oncologic population ^[5][1].

Graph: rCDI Rate with Bezlotoxumab vs. Placebo in Cancer Patients

Graph: Bar chart showing significant reduction in rCDI among cancer patients receiving bezlotoxumab compared to placebo (MODIFY pooled analysis)

Comparative Risk Reduction in Subgroups

Patients with additional risk factors (age ≥65, severe CDI, immunosuppression, ribotype 027/078/244) have the greatest reduction in rCDI with bezlotoxumab ^[6][3][1].

Bezlotoxumab is an effective and well-tolerated adjunct for prevention of recurrent CDI in cancer patients, especially those with multiple risk factors or immunosuppression. Real-world and clinical trial data support its use to reduce recurrences, hospitalization, and potentially mortality. Ongoing research and real-world data will clarify its optimal placement in oncologic infection management protocols.

1.      Gerding, D. N., et al. “Exploratory Evaluation of Bezlotoxumab on Outcomes Among Cancer Patients With Clostridioides difficile Infection.” Open Forum Infectious Diseases, vol. 7, no. 4, 2020, p. ofaa585.

2.      Wilcox, Mark H., et al. “Bezlotoxumab for Prevention of Recurrent Clostridium difficile Infection.” New England Journal of Medicine, vol. 376, no. 4, 2017, pp. 305–317.

3.      Cornely, Oliver A., et al. "Bezlotoxumab Treatment Reduced C diff Recurrence in Cancer Patients." Open Forum Infectious Diseases, 2020.

4.      Chapin, Ryan W., et al. "Bezlotoxumab: Could This be the Answer for Clostridium difficile Recurrence?" Annals of Pharmacotherapy, vol. 51, no. 9, 2017, pp. 678-684.