Abstract Published: 2017 Jan 26
Bezlotoxumab for Prevention of Recurrent Clostridium difficile Infection.
Recurrent Clostridium difficile Prevention
Wilcox MH1, Gerding DN1, Poxton IR1, Kelly C1, Nathan R1, Birch T1, Cornely OA1, Rahav G1, Bouza E1, Lee C1, Jenkin G1, Jensen W1, Kim YS1, Yoshida J1, Gabryelski L1, Pedley A1, Eves K1, Tipping R1, Guris D1, Kartsonis N1, Dorr MB1; MODIFY I and MODIFY II Investigators.
Background Clostridium difficile is the most common cause of infectious diarrhea in hospitalized patients. Recurrences are common after antibiotic therapy.
Actoxumab and bezlotoxumab are human monoclonal antibodies against C. difficile toxins A and B, respectively.
Methods – We conducted two double-blind, randomized, placebo-controlled, phase 3 trials, MODIFY I and MODIFY II, involving 2655 adults receiving oral standard-of-care antibiotics for primary or recurrent C. difficile infection. Participants received an infusion of bezlotoxumab (10 mg per kilogram of body weight), actoxumab plus bezlotoxumab (10 mg per kilogram each), or placebo; actoxumab alone (10 mg per kilogram) was given in MODIFY I but discontinued after a planned interim analysis.
The primary end point was recurrent infection (new episode after initial clinical cure) within 12 weeks after infusion in the modified intention-to-treat population.
Results In both trials, the rate of recurrent C. difficile infection was significantly lower with bezlotoxumab alone than with placebo (MODIFY I: 17% [67 of 386] vs. 28% [109 of 395]; adjusted difference, -10.1 percentage points; 95% confidence interval [CI], -15.9 to -4.3; P<0.001; MODIFY II: 16% [62 of 395] vs. 26% [97 of 378]; adjusted difference, -9.9 percentage points; 95% CI, -15.5 to -4.3; P<0.001) and was significantly lower with actoxumab plus bezlotoxumab than with placebo (MODIFY I: 16% [61 of 383] vs. 28% [109 of 395]; adjusted difference, -11.6 percentage points; 95% CI, -17.4 to -5.9; P<0.001; MODIFY II: 15% [58 of 390] vs. 26% [97 of 378]; adjusted difference, -10.7 percentage points; 95% CI, -16.4 to -5.1; P<0.001). In prespecified subgroup analyses (combined data set), rates of recurrent infection were lower in both groups that received bezlotoxumab than in the placebo group in subpopulations at high risk for recurrent infection or for an adverse outcome.
The rates of initial clinical cure were 80% with bezlotoxumab alone, 73% with actoxumab plus bezlotoxumab, and 80% with placebo; the rates of sustained cure (initial clinical cure without recurrent infection in 12 weeks) were 64%, 58%, and 54%, respectively.
The rates of adverse events were similar among these groups; the most common events were diarrhea and nausea.
Conclusions Among participants receiving antibiotic treatment for primary or recurrent
C. difficile infection, bezlotoxumab was associated with a substantially lower rate of recurrent infection than placebo and had a safety profile similar to that of placebo.
The addition of actoxumab did not improve efficacy. (Funded by Merck; MODIFY I and MODIFY II ClinicalTrials.gov numbers, NCT01241552 and NCT01513239 .).
Bezlotoxumab – A New Agent for Clostridium difficile Infection. [N Engl J Med. 2017]