Safety and Efficacy of Fidaxomicin Versus Placebo for Prophylaxis Against Clostridium Difficile-Associated Diarrhea in Adults Undergoing Hematopoietic Stem Cell Transplantation (MK-5119-001) (DEFLECT-1)
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ClinicalTrials.gov Identifier: NCT01691248 |
Recruitment Status :
Completed
First Posted : September 24, 2012
Results First Posted : April 12, 2016
Last Update Posted : September 18, 2018
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Condition or disease | Intervention/treatment | Phase |
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Clostridium Difficile-Associated Diarrhea (CDAD) | Drug: fidaxomicin Drug: Placebo | Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 611 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Double (Participant, Investigator) |
Primary Purpose: | Prevention |
Official Title: | DEFLECT-1: A Phase 3b Multi-Center, Double-Blind, Randomized, Placebo Controlled Study to Demonstrate the Safety and Efficacy of Fidaxomicin for Prophylaxis Against Clostridium Difficile-Associated Diarrhea in Adults Undergoing Hematopoietic Stem Cell Transplantation |
Actual Study Start Date : | October 10, 2012 |
Actual Primary Completion Date : | March 18, 2015 |
Actual Study Completion Date : | April 16, 2015 |

Arm | Intervention/treatment |
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Active Comparator: Fidaxomicin
200 mg Fidaxomicin tablet once daily for no longer than 40 days
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Drug: fidaxomicin
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. Other Names:
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Placebo Comparator: Placebo
Placebo tablet once daily for no longer than 40 days
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Drug: Placebo
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. |
- Percentage of Participants With Occurrence of CDAD From Start of Study Treatment up to 30 Days Post-treatment Follow-up. [ Time Frame: Up to 30 days post-treatment ]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 Occurrence of CDAD From Start of Study Treatment up to 60 Days Post-treatment. [ Time Frame: Up to 60 days post-treatment ]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 Occurrence of CDAD From Start of Study Treatment up to Day 70 of Study. [ Time Frame: Up to Day 70 of study ]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.

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Male or female 18 years of age or older.
- Females of childbearing potential must be using an adequate and reliable method of contraception (e.g., abstinence, barrier with additional spermicide foam or jelly, intrauterine device, hormonal contraception). Males and females must agree to avoid conception during treatment and for four weeks following the end of study treatment.
- Is undergoing HSCT with planned Fluoroquinolone prophylaxis.
- Informed consent is provided.
Exclusion Criteria:
- Ongoing active CDAD infection (as evidenced by clinical signs of diarrhea along with the presence of either toxin A and/or B [or their respective genes, tcdA and/or tcdB] of C. difficile in the stool) or current treatment for CDAD.
- Undergoing cord blood transplants.
- Has fulminant colitis, toxic megacolon, or ileus.
- A history of inflammatory bowel disease (ulcerative colitis or Crohn's disease).
- Women who are pregnant or are actively breast feeding (all women of childbearing potential must have a negative pregnancy test result prior to dosing study drug).
- Use of any drugs potentially useful in the treatment of CDAD (e.g. oral Vancomycin, Metronidazole, oral Bacitracin, Fusidic Acid, Rifaximin, and Nitazoxanide).
- Any other condition that, in the opinion of the investigator, would jeopardize the safety or rights of the participant in the study, would make it unlikely for the participant to complete the study, or would confound the results of the study.
- Participation in other clinical research studies utilizing an investigational agent within one month prior to screening and during the study treatment period.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01691248
Study Director: | Medical Director | Merck Sharp & Dohme LLC |
Responsible Party: | Optimer Pharmaceuticals LLC |
ClinicalTrials.gov Identifier: | NCT01691248 |
Other Study ID Numbers: |
5119-001 OPT-80-302 ( Other Identifier: Optimerpharma Study Number ) |
First Posted: | September 24, 2012 Key Record Dates |
Results First Posted: | April 12, 2016 |
Last Update Posted: | September 18, 2018 |
Last Verified: | August 2018 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Yes |
Plan Description: | https://www.merck.com/clinical-trials/pdf/ProcedureAccessClinicalTrialData.pdf |
URL: | http://engagezone.msd.com/ds_documentation.php |
Clostridium difficile Clostridium difficile-Associated Diarrhea Prophylaxis Hematopoietic Stem Cell Transplantation |
Clostridium Infections Diarrhea Signs and Symptoms, Digestive Gram-Positive Bacterial Infections Bacterial Infections |
Bacterial Infections and Mycoses Infections Fidaxomicin Anti-Bacterial Agents Anti-Infective Agents |