Trial Outcomes & Findings for Xpert MTB/Rif, a New Tool for the Diagnosis of Pulmonary Tuberculosis in Two Municipalities in Brazil (NCT NCT01363765)

NCT ID: NCT01363765

Last Updated: 2014-03-12

Results Overview

Proportion of additional bacteriologically confirmed notified TB cases during intervention period compared to the observation period Patients notified who had a positive test result. The notification rate (NR, i.e., number of notifications/100,000 population/year) ratio (NRR) is defined as the NR in the intervention period/NR in the observation period, and is presented in the statistical analysis section.

Recruitment status

COMPLETED

Study phase

PHASE4

Target enrollment

34758 participants

Primary outcome timeframe

October 2012 (up to 2 years)

Results posted on

2014-03-12

Participant Flow

From Feb 4 to Oct 4 2012, all 11 primary care laboratories in Rio de Janeiro and 3 labs covering 70% of PTB diagnosis in Manaus participated. Over the same period, 4,660 patients were notified with PTB to SINAN (disease information database). Of these, 2,745 (59%) could be linked to test results in GAL (lab information system).

Samples (and not patients) were included if it was a first diagnostic sample in the intervention arm. Follow up (non diagnostic) samples were excluded for both arms, as were inadequate samples (insufficient material, blood stained-specimens) in the intervention group.

Participant milestones

Participant milestones
Measure
Xpert MTB/Rif
Sputum specimens arriving during intervention period were submitted to this technology, a real-time automated polymerase chain reaction test
Sputum Smear
Sputum smears arriving in the laboratory during the observation period were submitted to the classic routine AFB smear staining, as per national guidelines. Two smears were requested.
Overall Study
STARTED
18322
16436
Overall Study
COMPLETED
12522
11705
Overall Study
NOT COMPLETED
5800
4731

Reasons for withdrawal

Reasons for withdrawal
Measure
Xpert MTB/Rif
Sputum specimens arriving during intervention period were submitted to this technology, a real-time automated polymerase chain reaction test
Sputum Smear
Sputum smears arriving in the laboratory during the observation period were submitted to the classic routine AFB smear staining, as per national guidelines. Two smears were requested.
Overall Study
non-diagnostic
2621
1124
Overall Study
duplicate records
736
3177
Overall Study
non-resident
156
76
Overall Study
age not recorded (used for cross-linkage
117
354
Overall Study
smear during intervention
2170
0

Baseline Characteristics

Xpert MTB/Rif, a New Tool for the Diagnosis of Pulmonary Tuberculosis in Two Municipalities in Brazil

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Xpert MTB/Rif
n=2610 Participants
One sample of sputum specimens arriving during intervention period were submitted to this technology instead, a real-time automated polymerase chain reaction test
Sputum Smear
n=2050 Participants
Sputum smears arriving in the laboratory during the observation period will be submitted to the classic routine smear staining
Total
n=4660 Participants
Total of all reporting groups
Age, Customized
Between 15 and 39 years
1395 participants
n=5 Participants
1068 participants
n=7 Participants
2463 participants
n=5 Participants
Age, Customized
Between 40 and 59 years
835 participants
n=5 Participants
682 participants
n=7 Participants
1517 participants
n=5 Participants
Age, Customized
>=60 years
324 participants
n=5 Participants
244 participants
n=7 Participants
568 participants
n=5 Participants
Age, Customized
<=14 years
56 participants
n=5 Participants
56 participants
n=7 Participants
112 participants
n=5 Participants
Sex: Female, Male
Female
928 Participants
n=5 Participants
736 Participants
n=7 Participants
1664 Participants
n=5 Participants
Sex: Female, Male
Male
1682 Participants
n=5 Participants
1314 Participants
n=7 Participants
2996 Participants
n=5 Participants
Region of Enrollment
Brazil
2610 participants
n=5 Participants
2050 participants
n=7 Participants
4660 participants
n=5 Participants

PRIMARY outcome

Timeframe: October 2012 (up to 2 years)

Population: Only patients found both in laboratory and in the notification databases were included since this is an outcome based on notification rates. Population growth during time was estimated. NR per 100,000 population

Proportion of additional bacteriologically confirmed notified TB cases during intervention period compared to the observation period Patients notified who had a positive test result. The notification rate (NR, i.e., number of notifications/100,000 population/year) ratio (NRR) is defined as the NR in the intervention period/NR in the observation period, and is presented in the statistical analysis section.

Outcome measures

Outcome measures
Measure
Xpert MTB/Rif
n=1385 Participants
One sample of sputum specimens arriving during intervention period was submitted to this technology
Sputum Smear
n=831 Participants
Sputum smears arriving in the laboratory during the observation period were submitted to the classic routine smear staining
Notification Rate Ratio
48.7 notifications/100,000 persons/year
Interval 41.5 to 55.8
30.5 notifications/100,000 persons/year
Interval 24.9 to 36.1

PRIMARY outcome

Timeframe: October 2012 (up to 2 years)

Costs per detected case were analyzed using a decision tree model from the national health system perspective. Incremental cost-effectiveness ratio (ICER) was calculated as (costs with Xpert - costs with smears)/(cases detected with Xpert - cases detected with smears). Negative ICERs mean cost saving.

Outcome measures

Outcome measures
Measure
Xpert MTB/Rif
n=12522 Participants
One sample of sputum specimens arriving during intervention period was submitted to this technology
Sputum Smear
n=11705 Participants
Sputum smears arriving in the laboratory during the observation period were submitted to the classic routine smear staining
Costs Per Detected Case
714.95 American dollars
799.02 American dollars

SECONDARY outcome

Timeframe: October 2012 (up to 2 years)

Population: The result is the notification rate ratio

The notification rate (NR, i.e., number of notifications/100,000 population/year) ratio (NRR) is defined as the NR in the intervention period/NR in the observation period, and is presented in the statistical analysis section. Numbers are participants in the notification database who were not in the lab (all tests done) database; denominators are population taking into account growth of the population during the study period, adjusted for variations in monthly number of opening days (by weighing the number of person-months for the proportion of suspects with samples examined each month out of the total number examined by the laboratory during the whole study period), stratified by sex and age group. Routine practices were not changed; patients with a high suspicion of TB were, as prior to the study, notified regardless of a confirmatory test.

Outcome measures

Outcome measures
Measure
Xpert MTB/Rif
n=1009 Participants
One sample of sputum specimens arriving during intervention period was submitted to this technology
Sputum Smear
n=906 Participants
Sputum smears arriving in the laboratory during the observation period were submitted to the classic routine smear staining
NRR of Non-laboratory Tested TB (Cluster-averaged).
35.8 notifications/100,000 persons/year
Interval 27.6 to 43.9
36.9 notifications/100,000 persons/year
Interval 26.8 to 47.1

SECONDARY outcome

Timeframe: October 2012 (up to 2 years)

The notification rate (NR, i.e., number of notifications/100,000 population/year) ratio (NRR) is defined as the NR in the intervention period/NR in the observation period, and is presented in the statistical analysis section. Numbers are driven from linkage between lab (all tests done) and notification databases; denominators are population taking into account growth of the population during the study period, adjusted for variations in monthly number of opening days (by weighing the number of person-months for the proportion of suspects with samples examined each month out of the total number examined by the laboratory during the whole study period), stratified by sex and age group. Routine practices were not changed; patients with a high suspicion of TB were, as prior to the study, notified regardless of a confirmatory test.

Outcome measures

Outcome measures
Measure
Xpert MTB/Rif
n=216 Participants
One sample of sputum specimens arriving during intervention period was submitted to this technology
Sputum Smear
n=313 Participants
Sputum smears arriving in the laboratory during the observation period were submitted to the classic routine smear staining
NRR of Negative-laboratory TB (Cluster-averaged).
7.3 notifications/100,000 persons/year
Interval 2.1 to 12.5
12.1 notifications/100,000 persons/year
Interval 6.1 to 18.0

Adverse Events

Xpert MTB/Rif

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Sputum Smear

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Anete Trajman

InCo-TB project, Gama Filho University

Phone: 5521-82189194

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place