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History of Changes for Study: NCT03090191
Clostridium Difficile Vaccine Efficacy Trial (Clover) (Clover)
Latest version (submitted October 4, 2022) on ClinicalTrials.gov
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Study Record Versions
Version A B Submitted Date Changes
1 March 20, 2017 None (earliest Version on record)
2 April 6, 2017 Recruitment Status, Outcome Measures, Study Status, Contacts/Locations, Arms and Interventions, Study Design and Study Identification
3 May 3, 2017 Contacts/Locations, Study Status, Study Design and Oversight
4 May 22, 2017 Contacts/Locations and Study Status
5 June 6, 2017 Contacts/Locations and Study Status
6 June 29, 2017 Contacts/Locations and Study Status
7 July 25, 2017 Contacts/Locations, Study Status and IPDSharing
8 August 15, 2017 Contacts/Locations and Study Status
9 September 13, 2017 Contacts/Locations and Study Status
10 October 11, 2017 Contacts/Locations and Study Status
11 November 21, 2017 Contacts/Locations and Study Status
12 December 15, 2017 Contacts/Locations and Study Status
13 January 19, 2018 Contacts/Locations and Study Status
14 February 6, 2018 Contacts/Locations and Study Status
15 February 13, 2018 Contacts/Locations and Study Status
16 March 16, 2018 Contacts/Locations and Study Status
17 March 23, 2018 Contacts/Locations and Study Status
18 April 13, 2018 Contacts/Locations and Study Status
19 April 30, 2018 Contacts/Locations and Study Status
20 May 15, 2018 Contacts/Locations and Study Status
21 June 1, 2018 Contacts/Locations and Study Status
22 June 14, 2018 Contacts/Locations and Study Status
23 July 11, 2018 Contacts/Locations and Study Status
24 July 17, 2018 Contacts/Locations and Study Status
25 August 2, 2018 Contacts/Locations and Study Status
26 August 15, 2018 Contacts/Locations and Study Status
27 September 7, 2018 Contacts/Locations and Study Status
28 October 8, 2018 Contacts/Locations and Study Status
29 October 30, 2018 Contacts/Locations and Study Status
30 December 14, 2018 Contacts/Locations and Study Status
31 February 25, 2019 Contacts/Locations, IPDSharing, Study Status, Study Design and Study Identification
32 June 13, 2019 Recruitment Status, Contacts/Locations, Study Status, Study Design and Outcome Measures
33 July 22, 2019 Study Status and Study Design
34 August 20, 2019 Study Status, References and Contacts/Locations
35 October 1, 2019 Contacts/Locations, Study Status and Study Design
36 October 25, 2019 Contacts/Locations, Study Design and Study Status
37 November 25, 2019 Study Status and Contacts/Locations
38 February 20, 2020 Contacts/Locations and Study Status
39 October 16, 2020 Contacts/Locations, Study Status and Study Design
40 December 14, 2020 Contacts/Locations and Study Status
41 December 16, 2020 Contacts/Locations and Study Status
42 December 29, 2020 Contacts/Locations and Study Status
43 January 11, 2021 Contacts/Locations and Study Status
44 February 8, 2021 Contacts/Locations and Study Status
45 February 18, 2021 Contacts/Locations and Study Status
46 February 22, 2021 Study Status
47 March 18, 2021 Contacts/Locations, Study Status and Study Design
48 April 7, 2021 Contacts/Locations and Study Status
49 August 18, 2021 Contacts/Locations, Study Status and Study Design
50 September 10, 2021 Study Status and Contacts/Locations
51 September 21, 2021 Contacts/Locations and Study Status
52 October 8, 2021 Study Status and Contacts/Locations
53 November 18, 2021 Contacts/Locations and Study Status
54 December 16, 2021 Study Status
55 January 5, 2022 Recruitment Status, Study Status and Contacts/Locations
56 January 20, 2022 Study Status, Contacts/Locations and Study Design
57 March 2, 2022 Contacts/Locations, Study Status and Study Design
58 April 8, 2022 Contacts/Locations and Study Status
59 May 11, 2022 Contacts/Locations, Study Status and Study Design
60 June 7, 2022 Contacts/Locations, Study Status and Study Design
61 August 17, 2022 Contacts/Locations, Study Status and Study Design
62 October 4, 2022 Contacts/Locations, Study Status and Study Design
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Study NCT03090191
Submitted Date:  March 20, 2017 (v1)

Open or close this module Study Identification
Unique Protocol ID: B5091007
Brief Title: Clostridium Difficile Vaccine Efficacy Trial (Clover) (Clover)
Official Title: A Phase 3, Placebo-controlled, Randomized, Observer-blinded Study To Evaluate The Efficacy, Safety, And Tolerability Of A Clostridium Difficile Vaccine In Adults 50 Years Of Age And Older
Secondary IDs: 2016-003866-14 [EudraCT Number]
CLOVER [Alias Study Number]
Open or close this module Study Status
Record Verification: March 2017
Overall Status: Not yet recruiting
Study Start: March 31, 2017
Primary Completion: September 28, 2020 [Anticipated]
Study Completion: September 28, 2020 [Anticipated]
First Submitted: March 20, 2017
First Submitted that
Met QC Criteria:
March 20, 2017
First Posted: March 24, 2017 [Actual]
Last Update Submitted that
Met QC Criteria:
March 20, 2017
Last Update Posted: March 24, 2017 [Actual]
Open or close this module Sponsor/Collaborators
Sponsor: Pfizer
Responsible Party: Sponsor
Collaborators:
Open or close this module Oversight
U.S. FDA-regulated Drug: Yes
U.S. FDA-regulated Device: No
Data Monitoring: Yes
Open or close this module Study Description
Brief Summary:

The Clover trial is evaluating an investigational vaccine that may help to prevent Clostridium difficile infection. Participants in the study are adults 50 years of age and older, who are at risk of developing Clostridium difficile infection. The study will assess whether the vaccine prevents the disease, and whether it is safe and well tolerated.

Each subject will receive 3 doses of Clostridium difficile vaccine or placebo and be followed for up to 3 years after vaccination for potential Clostridium difficile infection.

Detailed Description:
Open or close this module Conditions
Conditions: Clostridium Difficile Infection
Keywords:
Open or close this module Study Design
Study Type: Interventional
Primary Purpose: Prevention
Study Phase: Phase 3
Interventional Study Model: Parallel Assignment
Number of Arms: 2
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Allocation: Randomized
Enrollment: 15776 [Anticipated]
Open or close this module Arms and Interventions
Arms Assigned Interventions
Experimental: Clostridium difficile vaccine Biological: Clostridium difficile vaccine
Placebo Comparator: Placebo Biological: Placebo
Open or close this module Outcome Measures
Primary Outcome Measures:
1. First primary case CDI incidence per 1000 person-years of follow-up (confirmed at the central laboratory)
[ Time Frame: Up to 3 years after the 3rd dose. ]

2. First primary case CDI incidence per 1000 person-years of follow-up (confirmed at the central laboratory)
[ Time Frame: Up to 3.4 years after the 2nd dose. ]

3. Percentage of subjects reporting local reactions (pain, erythema, and induration), as self-reported on electronic diaries.
[ Time Frame: Up to 7 days following each vaccination, 1, 2, and 3. ]

4. Percentage of subjects reporting systemic events (fever, vomiting, headache, fatigue, new or worsening muscle pain, and new or worsening joint pain), as self-reported on electronic diaries.
[ Time Frame: Up to 7 days following each vaccination, 1, 2, and 3. ]

5. Percentage of subjects reporting nonserious adverse events.
[ Time Frame: Up to 7 months after the first dose. ]

6. Percentage of subjects reporting serious adverse events.
[ Time Frame: Up to 12 months after the first dose. ]

Secondary Outcome Measures:
1. Recurrent case CDI incidence per 1000 person-years of follow-up (confirmed at the central laboratory).
[ Time Frame: Up to 3 years after the 3rd dose. ]

2. Recurrent case CDI incidence per 1000 person-years of follow-up (confirmed at the central laboratory).
[ Time Frame: Up to 3.4 years after the 2nd dose. ]

3. First primary case CDI incidence per 1000 person-years of follow-up (including local laboratory demonstration of the presence of Clostridium difficile).
[ Time Frame: Up to 3 years after the 3rd dose. ]

4. First primary case CDI incidence per 1000 person-years of follow-up (including local laboratory demonstration of the presence of Clostridium difficile).
[ Time Frame: Up to 3.4 years after the 2nd dose. ]

5. Recurrent case CDI incidence per 1000 person-years of follow-up (including local laboratory demonstration of the presence of Clostridium difficile).
[ Time Frame: Up to 3 years after the 3rd dose. ]

6. Recurrent case CDI incidence per 1000 person-years of follow-up (including local laboratory demonstration of the presence of Clostridium difficile).
[ Time Frame: Up to 3.4 years after the 2nd dose. ]

7. In subjects that receive only 2 doses, first primary CDI incidence per 1000 person-years of follow-up (confirmed at the central laboratory).
[ Time Frame: Up to 3.4 years after the 2nd dose. ]

8. In subjects that receive only 2 doses, recurrent case CDI incidence per 1000 person-years of follow-up (confirmed at the central laboratory).
[ Time Frame: Up to 3.4 years after the 2nd dose. ]

9. In subjects that receive only 2 doses, first primary case CDI incidence per 1000 person-years of follow-up (including local laboratory demonstration of the presence of Clostridium difficile).
[ Time Frame: Up to 3.4 years after the 2nd dose. ]

10. In subjects that receive only 2 doses, recurrent case CDI incidence per 1000 person-years of follow-up (including local laboratory demonstration of the presence of Clostridium difficile).
[ Time Frame: Up to 3.4 years after the 2nd dose. ]

11. All case CDI incidence per 1000 person-years of follow-up (confirmed at the central laboratory).
[ Time Frame: Up to 3 years after the 3rd dose. ]

12. All case CDI incidence per 1000 person-years of follow-up (including local laboratory demonstration of the presence of Clostridium difficile).
[ Time Frame: Up to 3 years after the 3rd dose. ]

13. All case CDI incidence per 1000 person-years of follow-up (confirmed at the central laboratory).
[ Time Frame: Up to 3.4 years after the 2nd dose. ]

14. All case CDI incidence per 1000 person-years of follow-up (including local laboratory demonstration of the presence of Clostridium difficile).
[ Time Frame: Up to 3.4 years after the 2nd dose. ]

15. Mean time to resolution of diarrhea in first primary cases of CDI (confirmed at the central laboratory).
[ Time Frame: Up to 3.5 years after enrolment. ]

16. Proportion of subjects experiencing a first primary episode of CDI (confirmed at the central laboratory) who have a non-protocol-related medically attended visit during the CDI episode.
[ Time Frame: Up to 3.5 years after enrolment. ]

17. Mean ATLAS (age, treatment with systemic antibiotics during CDI therapy, leukocyte count, serum albumin, and serum creatinine) score.
[ Time Frame: Up to 3.5 years after enrolment. ]

Open or close this module Eligibility
Minimum Age: 50 Years
Maximum Age:
Sex: All
Gender Based:
Accepts Healthy Volunteers: Yes
Criteria:

Inclusion Criteria:

  • Evidence of a personally signed and dated informed consent document.
  • Willing and able to comply with study procedures.
  • Subjects with an increased risk of future contact with healthcare systems or subjects who have received systemic antibiotics in the previous 12 weeks.
  • Ability to be contacted by telephone during study participation.
  • Negative urine pregnancy test for female subjects of childbearing potential.

Exclusion Criteria:

  • Investigator site staff members directly involved in the conduct of the study and their family members, site staff members otherwise supervised by the investigator, or subjects who are Pfizer employees, including their family members, directly involved in the conduct of the study.
  • Participation in other studies involving investigational drug(s)/vaccine(s) within 28 days prior to study entry until 1 month after the third vaccination.
  • Previous administration of an investigational C difficile vaccine or C difficile mAb therapy.
  • Prior episode of CDI..
  • Receipt of blood products or immunoglobulins within 6 months before enrollment.
  • Subjects who may be unable to respond to vaccination due to:
    • Metastatic malignancy; or
    • End-stage renal disease; or
    • Any serious medical disorder likely to be fatal within the next 12 months; or
    • Congenital or acquired immunodeficiency; or
    • Receipt of high dose systemic corticosteroids for 14 days within 28 days of enrollment; or
    • Receipt of chronic systemic treatment with other known immunosuppressant medications, or radiotherapy, within 6 months of enrollment.
  • Known infection with human immunodeficiency virus (HIV).
  • Any bleeding disorder or anticoagulant therapy that would contraindicate intramuscular injection.
  • Any contraindication to vaccination or vaccine components, including previous anaphylactic reaction to any vaccine or vaccine-related components.
  • Prior small- or large-bowel resection.
  • Any condition or treatment resulting in frequent diarrhea.
  • Other acute or chronic condition or abnormality that may increase the risk associated with study participation or IP administration or may interfere with interpretation of study results
  • Pregnant or breastfeeding female subjects; male subjects and female subjects who are sexually active and at risk for pregnancy and will not/cannot use 2 methods of contraception
Open or close this module Contacts/Locations
Central Contact Person: Pfizer CT.gov Call Center
Telephone: 1-800-718-1021
Study Officials: Pfizer CT.gov Call Center
Study Director
Pfizer
Locations:
Open or close this module IPDSharing
Plan to Share IPD: Yes

Information relating to our policy on data sharing and the process for requesting data can be found at the following link:

http://www.pfizer.com/research/clinical_trials/trial_data_and_results/data_requests

Supporting Information:
Time Frame:
Access Criteria:
URL:

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