Approval Probability
TA Base Rate
Adjusted LOA
ML Risk
Fidaxomicin · 6 trials · 9 indications
Initial clinical response (ICR) for ages from birth to \< 2 years was defined as absence of watery diarrhea for 2 consecutive treatment days, remaining well until study drug discontinuation. ICR for ages ≥ 2 years to \< 18 years was defined as improvement in number and character of bowel movements as determined by \< 3 unformed bowel movements (UBMs) per day for 2 consecutive treatment days, remaining well until study drug discontinuation. CCR was defined for both age groups as not requiring further CDAD therapy within 2 days after study drug completion, and was reported with a positive (Yes) or negative (No) outcome. Resolution of diarrhea was assessed during interviews of participant/parent/legal guardian, supplemented by review of personal records (if hospitalized) and checked for presence of watery diarrhea (ages from birth to \< 2 years) or number of UBMs (for ages ≥ 2 years to \< 18 years).
CDAD is defined as follows: Diarrhea: (change in bowel habits with \>3 unformed bowel movements in a 24 hour period) and the presence of either toxin A and/or B (or their respective genes, tcdA and/or tcdB) of C. difficile in the stool determined by C. difficile toxin assay. Wald 95% Confidence Intervals (CI) are presented.
Percentage of participants with 3 or fewer unformed stools for 2 consecutive days and maintained through the end of therapy, and the subject no longer needed specific anti-Clostridium antibacterial treatment after completion of the course of study medication.
Number of participants with adverse events, as categorized by MedDRA.
3-5 hour plasma levels of fidaxomicin (mean)
End of therapy fecal levels of fidaxomicin (mean)
3-5 hour plasma levels of OP-1118 (mean)
End of therapy fecal levels of OP-1118 (mean)
Single Dose
Single Dose
Last Dose
Last Dose
Cmax (maximum observed concentration)
AUCinf (area under the concentration time curve from time zero extrapolated to infinity)
| Arm | Type | Description |
|---|---|---|
| Fidaxomicin | EXPERIMENTAL | Participants from birth to \< 6 years of age received weight based doses of fidaxomicin oral suspension (32 mg/kg/day with a maximum dose of 400 mg/day divided in 2 doses) 2 times daily for 10 days. Participants aged ≥ 6 years to \< 18 years of age received a 200 mg fidaxomicin tablet 2 times daily for 10 days. |
| Vancomycin | ACTIVE_COMPARATOR | Participants from birth to \< 6 years of age received weight based doses of vancomycin oral liquid (40 mg/kg/day with a maximum dose of 500 mg/day divided in 4 doses) 4 times daily for 10 days. Participants aged ≥ 6 years to \< 18 years of age received a 125 mg vancomycin capsule 4 times daily for 10 days. |
| Placebo | PLACEBO_COMPARATOR | Placebo tablet once daily for no longer than 40 days |
| Cohort 1: Fidaxomicin low dose in Japanese males | EXPERIMENTAL | - |
| Cohort 2: Fidaxomicin high dose in Japanese males | EXPERIMENTAL | - |
| Cohort 3: Fidaxomicin high dose in Caucasian males | EXPERIMENTAL | - |
| Matching Placebo in Caucasian males | PLACEBO_COMPARATOR | - |
| Matching Placebo in Japanese males | PLACEBO_COMPARATOR | - |
| 1:Single rosuvastatin,multiple fidaxomicin,single rosuvastatin | EXPERIMENTAL | - |
| 2:Multiple fidaxomicin,single rosuvastatin,single rosuvastatin | EXPERIMENTAL | - |
| Name | Type | Description |
|---|---|---|
| Fidaxomicin oral suspension | DRUG | Participants from birth to \< 6 years of age received weight based doses of fidaxomicin oral suspension (32 mg/kg/day with a maximum dose of 400 mg/day divided in 2 doses) 2 times daily for 10 days. |
| Fidaxomicin tablets | DRUG | Participants aged ≥ 6 years to \< 18 years of age received a 200 mg fidaxomicin tablet 2 times daily for 10 days. |
| Vancomycin oral liquid | DRUG | Participants from birth to \< 6 years of age received weight based doses of vancomycin oral liquid (40 mg/kg/day with a maximum dose of 500 mg/day divided in 4 doses) 4 times daily for 10 days. |
| Vancomycin capsules | DRUG | Participants aged ≥ 6 years to \< 18 years of age received a 125 mg vancomycin capsule 4 times daily for 10 days. |
| fidaxomicin | DRUG | Fidaxomicin 200 mg tablet once daily from the start (+/- 2 days) of condition (prior to transplantation) or at the time of Fluoroquinolone initiation. Study drug treatment will continue until 7 days after either neutrophil engraftment or the completion of any Fluoroquinolone antibiotic regimen (whichever occurs later). Study drug treatment will stop at onset of CDAD or no longer than 40 days of duration, even if other antibiotics are still administered or neutrophil engraftment extends beyond 40 days. |
| Placebo | DRUG | Placebo tablet once daily from the start (+/- 2 days) of condition (prior to transplantation) or at the time of Fluoroquinolone initiation. Treatment will continue until 7 days after either neutrophil engraftment or the completion of any Fluoroquinolone antibiotic regimen (whichever occurs later). Treatment will stop at onset of CDAD or no longer than 40 days of duration, even if other antibiotics are still administered or neutrophil engraftment extends beyond 40 days. |
| Vancomycin | DRUG | 125 mg capsules q6hr (4 times a day) |
| Matching Placebo to Fidaxomicin | DRUG | Matching Placebo to Fidaxomicin administered two times daily (intermittently with fidaxomicin dosing) |
| rosuvastatin | DRUG | Oral |
Inclusion Criteria: * Subject is diagnosed with CDAD according to local diagnostic criteria. As a minimum there must be positive detection, within 72 hours prior to randomization, of either toxin A and/or toxin B in stool or positive detection of toxigenic C. difficile in stool and: * Subject fr...
Fidaxomicin is used for Clostridium difficile-associated diarrhea (CDAD), also called Clostridium difficile infection. It is a small molecule gastrointestinal drug being developed by Merck & Company, Inc. (MRK). Fidaxomicin is an investigational agent and has been studied in clinical trials for the treatment of CDAD.
Fidaxomicin is a macrocyclic antibiotic that targets Clostridium difficile bacteria. It works by inhibiting bacterial RNA polymerase, which disrupts bacterial protein synthesis and leads to bacterial cell death. This mechanism is specific to the treatment of Clostridium difficile infections.
Fidaxomicin is developed by Merck & Company, Inc., which trades under the ticker MRK. Merck is conducting clinical trials to evaluate fidaxomicin for the treatment of Clostridium difficile-associated diarrhea (CDAD).
Fidaxomicin has completed Phase 3 clinical trials for Clostridium difficile-associated diarrhea (CDAD). The Phase 3 trial, NCT00314951, compared fidaxomicin to vancomycin in 629 patients. Fidaxomicin is not yet approved and remains an investigational drug in clinical development.
Fidaxomicin has been studied in several completed trials. NCT00314951 was a Phase 3 trial comparing fidaxomicin to vancomycin for CDAD in 629 patients. NCT01591863 was a Phase 2 pediatric trial in 38 subjects with CDAD. NCT01813448 and NCT02083627 were Phase 1 pharmacokinetic and drug-drug interaction studies in healthy volunteers.
Fidaxomicin is also known by the development code OPT-80. It is a macrocyclic antibiotic being developed by Merck & Company, Inc. for the treatment of Clostridium difficile-associated diarrhea (CDAD). The drug has been evaluated in Phase 3 clinical trials.