Results of the search
We retrieved 139 records from the search of the electronic database and no other records from other sources (Fig. 1). A total of 94 records were screened after duplicates were removed. We reviewed full copies of 13 and assessed them for eligibility. We identified four articles as possibly meeting the review inclusion criteria, and nine of them were ineligible for inclusion. One article was a non-randomized controlled trial that evaluated the clinical response of elagolix-treated women who did not achieve the primary outcome (22). Two reviews, one on predictors of response to elagolix with add-back therapy and the other on medical treatment of uterine leiomyoma, were relevant to our research query (4, 23). There was no outcome of interest in the four papers as two papers (3, 11) on elagolix pharmacotherapy and pharmacodynamics and another two more papers (14, 24) on drug-drug interactions were written. Adenomyosis was the topic of two more publications (25, 26). We attempted to contact the trial authors for the full article but received no response. Therefore, we included four trials.
Table 1
Characteristics of included trial
Reference
|
Country
|
Participants
|
Inclusion study period/ Treatment period
|
Intervention
|
Elagolix dosage and frequency administration
|
Comparator
|
No of participants/ No of trial sites
|
No of missing
|
Age group; mean baseline MBL
|
Mean baseline uterine volume / mean baseline fibroid volume
|
Archer 2017
|
USA
|
20–49 years;
267 mL
|
535 ± 389 cm3 / 91 ± 175 cm3
|
September 2011-May 2014 /
3 months
|
Elagolix
(ABT-620)
|
i; 100 mg bd
ii; 200 mg bd
iii; 300 mg bd
iv; 400 mg qd
v; 600 mg qd
|
i; placebo (matching placebo tablet)
ii; 0.5 mg E2/ 0.1 md NETA
|
271/ 45
|
Intervention (29)
Control (14)
|
Carr 2018
|
USA
|
18–51 years; 246 ± 180 mL
|
628 ± 462 cm3/ 150 ± 196 cm3
|
April 2013-Dec 2015/ 6 months
|
Elagolix
(ABT-620)
|
i; 300 mg bd
ii; 600 mg qd
|
i; placebo
(Oral coated placebo)
ii; 0.5 mg E2/ 0.1 mg NETA
iii; 1.0 mg E2/ 0.5 mg NETA
|
571*/ 86
*4 women were randomized but not treated
|
Intervention (32)
Control (97)
|
Schlaff 2020
|
USA
|
(UF-1)
18–51 years;
245 ± 161 mL
(UF-2)
18–51 years;
234 ± 156 mL
|
(UF-1)
482 ± 393 cm3 / 50 ± 68.9 cm3
(UF-2)
519 ± 437 cm3 / 63 ± 111 cm3
|
(UF-1)
Dec 2015- Dec 2018/ 6 months
(UF-2)
Feb 2016 – Feb 2018 /
6 months
|
Elagolix
(ABT-620)
|
i; 300 mg bd
|
i; placebo (film coated placebo tab)
ii; 1.0 mg E2/ 0.5 mg NETA
|
(UF-1)
413
(UF-2)
378
/77
|
(UF-1)
Intervention (23)
Control (62)
(UF-2)
Intervention (26)
Control (63)
|
Simon 2020
UF EXTEND
|
USA
|
18–51 years;
236 ± 159 mL
|
519 ± 457 cm3 / 59 ± 97 cm3
|
September 2016- Mac 2019/
12 months
|
Elagolix
(ABT-620)
|
i; 300 mg bd
|
i; 1.0 mg E2/ 0.5 mg NETA
|
316 out of 433 recruited*/ 115
*117 placebo participants exempted
|
Intervention (19)
Control (36)
|
MBL-menstrual blood loss; UF-1 – elaris uterine fibroid-1; UF-2 – elaris uterine fibroid − 2; RCT-randomized controlled trial; USA-united states of America; bd-twice daily; qd-once daily; E2 - estradiol; NETA – norethindrone acetate
* 117 placebo participants in pivotal study (Schlaff 2020) exempted as not fulfills eligibility criteria; UF-EXTEND-Uterine Fibroid extend is an additional 6-month for total up to 12-month treatment period.
Add-back therapy; elagolix with estradiol/norethindrone acetate
|
Included studies
Four randomized controlled trials with 1949 participants were included in the study (27–30). All four trials reported the primary outcome. All trials were sponsored by AbbVie (27–30).
Participants
All four studies were carried out in 323 locations across the United States, Puerto Rico, and Canada. One trial recruited participants from clinic settings (27). The other three trials did not mention the location from which participants were recruited (28–30). Three studies included premenopausal women aged 18 to 51 at the screening time (28–30), while one study recruited participants aged 20–49 (27). They underwent ultrasonography-confirmed diagnosis of uterine fibroids and heavy menstrual bleeding, as characterized by more than 80 ml of menstrual blood loss per menstrual cycle for at least two cycles. The trials excluded participants due to a complex ovarian cyst, cancer, pelvic inflammatory disorder, osteoporosis history, or metabolic bone disease. Participants who had a myomectomy or hysterectomy for symptomatic uterine fibroid were exempted from the study (27–30).
Intervention
Participants in the trials were randomized to the intervention and comparison groups. Two identical, double-blind, randomized, placebo-controlled, six-month phase 3 trials (Elaris Uterine Fibroids 1 and Elaris Uterine Fibroid 2) have been reported in one trial (29). Elaris Uterine Fibroid-1 and Elaris Uterine Fibroid-2 participants were later randomized or pooled into a new study (30) to look at the long-term twelve-month safety and efficacy of elagolix with or without estradiol/norethindrone acetate. The meta-analysis included four trials that evaluated the primary outcomes. Three trials compared elagolix with placebo (27–29), and four trials compared to elagolix with estradiol/norethindrone acetate (27–30). Only one trial compared elagolix to placebo at different doses of 100 mg bd, 200 mg bd, 300 mg bd, 400 mg qd, and 600 mg qd (27). One study was compared to placebo at doses of 300 mg bd and 600 mg qd (28). Another trial was compared elagolix to placebo at a dose of 300 mg bd (29).
In a comparison of elagolix to elagolix with estradiol/norethindrone acetate, one trial compared it at a dose of 0.5 mg estradiol/ 0.1 mg norethindrone acetate (27), while two trials compared it at a dose of 1.0 mg estradiol/ 0.5 mg norethindrone acetate (29, 30). In one trial, elagolix was compared to elagolix with estradiol/norethindrone acetate at two doses: 0.5 mg estradiol/0.1 mg norethindrone acetate and 1.0 mg estradiol/0.5 mg norethindrone acetate (28). All medications are taken orally as tablets or capsules. The duration of treatment differed between trials compared to elagolix versus placebo, as only one trial was three months (27), and the other two trials were six months (28, 29). In contrast, the length of treatment differed between trials when comparing elagolix to elagolix with estradiol/norethindrone acetate, with a three-month (27), a six-month (28, 29), and a twelve-month (30) period.
Outcomes
The validated alkaline hematin method was used to quantify and evaluate the primary outcome in all four trials (27–30). Any spotting or bleeding episodes on a sanitary pad were reported at the time of screening or during treatment. Participants kept an electronic daily bleeding diary (eDiary) and assessed bleeding patterns using the validated Mansfield-Voda-Jorgenson Menstrual Bleeding Scale (31). All studies were followed up to at least three-months duration. The primary outcome was measured during the last month of the treatment period.
All four trials reported all secondary outcomes except for one study (27), which did not record bone mineral density due to a limited study time and a small sample size per group. Reduction of uterine and fibroid volume was calculated using trans abdominal or transvaginal ultrasound. The mean percentage change from baseline to the end of the treatment month was recorded.
The Uterine Fibroid Symptom and Quality of Life questionnaire’s cumulative score were used to measure symptom severity reduction and change in health-related quality of life in women with symptomatic uterine fibroids. It was a disease-specific, self-administered, validated questionnaire. There were 37 questions in all, split into two parts. The first part consisted of an 8-item symptom severity scale. The second part consisted of a 29-item health-related quality of life subscale with six domains (concern, behaviors, energy/mood, power, self-consciousness, and sexual function). All items are rated on a 5-point scale, with symptom intensity items ranging from “not at all” to “a great deal”, and health-related quality of life items ranging from “none of the time” to “all of the time”. The cumulative score for each of the two components was determined by adding the symptom intensity and health-related quality of life subscale scores and translating them to a 0-to-100-point scale. Higher overall health-related quality of life scores indicated better quality of life, while lower symptom severity scores indicate better quality of life.
The percentage of increase in hemoglobin concentration from baseline to the last month of treatment was reported in all trials. Loss of bone mineral density was assessed by dual-energy x-ray absorptiometry scans of the lumbar spine, total hip, and femoral neck. The mean percentage change in bone mineral density from baseline to the last month of treatment was recorded in three studies (28–30). Any adverse events were recorded beginning with the first dose of the study drug and continuing for up to 30 days after completing the last dose of the study drug. All four trials identified common adverse events such as hot flushes, headaches, nausea, and fatigue. In this review, only two trials documented adverse events such as abdominal pain, dizziness, and hypertension (27, 28). Other non-significant adverse events identified in clinical trials will not be addressed in this review.
Risk of bias in included studies
The assessment risk of bias is shown in Fig. 2 and Fig. 3. Figure 2 shows the proportion of studies assessed as low, high or unclear risk of bias for each risk of bias indicator. Figure 3 shows the risk of bias indicators for individual studies. The details of these trials are found in the table of characteristics of included studies (Table 1).
Allocation
Only one trial, with 271 participants, was reported to have been recruited in a clinic setting, while the other three were not (27). The method of randomization was not reported in all four trials (27–30). Thus, we judged random sequence generation as having an unclear risk of bias. Allocation concealment was not mentioned and regarded as unclear in four trials (27–30).
Blinding
Participants, care provider, investigator and outcome assessor were masked in all four trials. The details on blinding were not recorded in all four trials, but the outcomes were unlikely to be influenced as it was objectively collected and measured using standardized methods (27–30). Therefore, they are judged as having a low risk of bias.
Incomplete outcome data
More than 80% of participants completed the studies in two trials (27, 30). Meanwhile, 74.4% of participants in one trial completed the study (28). Approximately 129 of the 571 participants failing to complete the analysis due to hypoestrogenism side effects (n = 39), withdrawal (n = 38), loss of follow up (n = 25), noncompliance (n = 11), lack of efficacy (n = 3), surgery (n = 4) and other (n = 9) (28). About 78% of 791 participants completed studies in Elaris Uterine Fibroid-1 and Elaris Uterine Fibroid-2 (29). The study drug was discontinued by similar proportions of women in both treatment groups (16.5 % for elagolix with estradiol/norethindrone acetate and 19.4 % for elagolix alone), with the most common primary reason being lost to follow-up (5.0% and 5.1%, respectively) in one trial (29). Missing data were evenly balanced across groups, and the reasons were similar. The most common reasons for missing outcome data included withdrawal, noncompliance, loss to follow up, hypoestrogenism side effects, pregnancy, and surgery, which led to discontinuation.
Selective reporting
All four trials reported the outcomes as specified in their methods Sect. (27–30). The outcomes listed in the registered protocol were those reported. Although changes in bone mineral density were assessed as an exploratory parameter, one trial did not report due to the short duration of the study and the relatively small sample size per group (27). We graded it as having a low risk of bias.
Other potential source of bias
We discovered that women with asymptomatic anemia and a hemoglobin level of less than 12 g/dl at screening or during the study period were advised to take iron supplements in two trials (27, 30). This could have an influence on the hemoglobin level at the end of the treatment period. Thus, we judged it as having a high risk of bias. We detected no other potential source of bias in the other two trials (28, 29).
Effects of intervention
There would be two comparisons evaluated in this review, i.e., comparing elagolix versus placebo and comparing elagolix versus estradiol/norethindrone acetate.
A) Comparison between elagolix and placebo
Elagolix has increased the number of patients with a reduction of menstrual blood loss of less than 80 ml (RR 4.81, 95% CI 2.45 to 9.45; I² statistic = 89%; P < 0.001; four trials, 869 participants; moderate quality evidence) (Fig. 4, Table 2) (27–29) or more than 50% from baseline (RR 4.87, 95% CI 2.55 to 9.31; I² statistic = 87%; P < 0.001; four trials, 869 participants; moderate quality evidence) (Fig. 5, Table 2) (27–29) compared to placebo. The sensitivity analysis did not change the cumulative effect estimate. Table 3 showed the subgroup analysis for reduction of menstrual blood loss of less than 80 ml or more than 50% reduction from baseline stratified by frequency of drug administration, uterine and fibroid volume (Additional File 1).
Table 2
Summary of findings including GRADE quality assessment for comparison between elagolix and placebo
Certainty assessment
|
No of patients
|
Effect
|
Certainty
|
No of studies
|
Study design
|
Risk of bias
|
Inconsistency
|
Indirectness
|
Imprecision
|
Other consideration
|
Elagolix
|
Placebo
|
Relative (95% CI)
|
Absolute (95% CI)
|
Reduction of menstrual blood loss of less than 80 ml
|
4
|
Randomized trials
|
not serious a
|
serious b
|
not serious
|
not serious
|
none
|
414/485 (85.4%)
|
80/834 (20.8%)
|
RR 4.81
(2.45 to 9.45)
|
794 more per 1,000
(from 302 more to 1,000 more)
|
⨁⨁⨁◯
MODERATE
|
Reduction of more than 50% menstrual blood loss
|
4
|
Randomized trials
|
not serious
|
serious c
|
not serious
|
not serious
|
none
|
416/485 (85.8%)
|
78/384 (20.3%)
|
RR 4.87
(2.55 to 9.31)
|
362 more per 1,000
(from 231 more to 528 more)
|
⨁⨁⨁◯
MODERATE
|
Improvement in hemoglobin level
|
4
|
Randomized trials
|
not serious
|
not serious
|
not serious
|
serious
|
none
|
196/320 (61.3%)
|
58/234 (24.8%)
|
RR 2.46
(1.93 to 3.13)
|
786 more per 1,000
(from 315 more to 1,000 more)
|
⨁⨁⨁◯
MODERATE
|
Adverse event (Hot flush)
|
4
|
Randomized trials
|
not serious
|
not serious e
|
not serious
|
serious d
|
none
|
259/501 (51.7%)
|
25/389 (6.4%)
|
RR 7.47
(4.99 to 11.18)
|
416 more per 1,000
(from 256 more to 654 more)
|
⨁⨁⨁◯
MODERATE
|
Uterine volume
|
4
|
Randomized trials
|
not serious
|
serious f
|
not serious
|
not serious
|
none
|
424
|
359
|
-
|
MD 34.5 lower
(43.48 lower to 25.53 lower)
|
⨁⨁⨁◯
MODERATE
|
Fibroid volume
|
4
|
Randomized trials
|
not serious
|
serious g
|
not serious
|
not serious
|
none
|
406
|
344
|
-
|
MD 31.39 lower
(44.69 lower to 18.09 lower)
|
⨁⨁⨁◯
MODERATE
|
Symptom severity
|
4
|
Randomized trials
|
not serious
|
very serious h
|
not serious
|
not serious
|
none
|
445
|
369
|
-
|
MD 31.54 lower
(41.85 lower to 21.22 lower)
|
⨁⨁◯◯
LOW
|
Health-related quality of life
|
4
|
Randomized trials
|
not serious
|
very serious
|
not serious
|
not serious
|
none
|
443
|
369
|
-
|
MD 30.64 higher
(20.14 higher to 41.15 higher)
|
⨁⨁◯◯
LOW
|
Bone mineral density (Lumbar spine)
|
3
|
Randomized trials
|
Not serious
|
Not serious
|
Not serious
|
Serious
|
none
|
281
|
293
|
-
|
MD 2.82 lower (3.3 lower to 2.35 lower)
|
⨁⨁⨁◯
MODERATE
|
Bone mineral density (Total hip)
|
3
|
Randomized trials
|
Not serious
|
Not serious
|
Not serious
|
Serious
|
none
|
281
|
293
|
-
|
MD 1.97 lower (2.37 lower to 1.57 lower)
|
⨁⨁⨁◯
MODERATE
|
Bone mineral density (Femoral neck)
|
3
|
Randomized trials
|
Not serious
|
Not serious
|
Not serious
|
Serious
|
none
|
281
|
293
|
-
|
MD 1.92 lower (2.61 lower to 1.23 lower)
|
⨁⨁⨁◯
MODERATE
|
Table 3
Summary of findings, including GRADE quality assessment for the comparison between elagolix and placebo by subgroup analysis
Outcome/Subgroup
|
No of trials
|
No of participants
|
Risk Ratio (RR)
|
95% Confidence interval (CI)
|
P value
|
Random effect; I2 statistic
|
GRADE quality
|
Reduction of menstrual blood loss of less than 80 ml
|
Frequency of drug administration
|
Twice a day (bd)
|
4
|
663
|
4.90
|
2.59, 9.25
|
P < 0.001
|
84%
|
Low
|
Once a day (qd)
|
2
|
223
|
3.35
|
1.28, 8.78
|
P = 0.010
|
59%
|
Low
|
Uterine volume
|
< 500 cm3
|
2
|
311
|
8.75
|
4.97, 15.42
|
P < 0.001
|
0%
|
Moderate
|
> 500 cm3
|
3
|
558
|
3.66
|
1.96, 6.83
|
P < 0.001
|
84%
|
Very low
|
Fibroid volume
|
< 50 cm3
|
2
|
252
|
8.77
|
4.98, 15.45
|
P < 0.001
|
0%
|
Moderate
|
> 50 cm3
|
3
|
632
|
3.85
|
2.09, 7.09
|
P < 0.001
|
84%
|
Very low
|
Reduction of more than 50% menstrual blood loss
|
Frequency of drug administration
|
Twice a day (bd)
|
4
|
663
|
5.00
|
2.74, 9.13
|
P < 0.001
|
82%
|
Low
|
Once a day (qd)
|
2
|
221
|
2.47
|
1.87, 3.26
|
P < 0.001
|
0%
|
Moderate
|
Uterine volume
|
< 500 cm3
|
2
|
311
|
8.75
|
4.97, 15.42
|
P < 0.001
|
0%
|
Moderate
|
> 500 cm3
|
3
|
558
|
3.75
|
2.06, 6.82
|
P < 0.001
|
82%
|
Very low
|
Fibroid volume
|
< 50 cm3
|
2
|
252
|
4.66
|
0.92, 21.71
|
P = 0.060
|
92%
|
Very low
|
> 50 cm3
|
3
|
632
|
3.92
|
2.19, 7.03
|
P < 0.001
|
82%
|
Very low
|
For the secondary outcomes, elagolix has increased the number of patients with improved hemoglobin level (RR 2.46, 95% CI 1.93 to 3.13; I² statistic = 0%; P < 0.001; four trials, 554 participants; moderate quality evidence) (27–29), reduced the mean percentage change in uterine volume (MD -34.50, 95% CI -43.48 to -25.53; I² statistic = 63%; P < 0.001; four trials, 783 participants; moderate quality evidence) (27–29), fibroid volume (MD -31.39, 95% CI -44.69 to -18.09; I² statistic = 65%; P < 0.001; four trials, 750 participants; moderate quality evidence) (27–29), severity of symptoms (MD -31.54, 95% CI -41.85 to -21.22; I² statistic = 96%; P < 0.001; four trials, 814 participants; low quality evidence) (27–29), and improved health-related quality of life (MD 30.64, 95% CI 20.14 to 41.15; I² statistic = 95%; P < 0.001; four trials, 812 participants; low quality evidence) (27–29) (Additional File 1, Table 2) compared to placebo.
Elagolix has reduced bone mineral density in lumbar spine (MD -2.82, 95% CI -3.30 to -2.35; I² statistic = 0%; P < 0.001; three trials, 574 participants; moderate quality evidence) (28, 29), total hip (MD -1.97, 95% CI -2.37 to -1.57; I² statistic = 46%; P < 0.001; three trials, 574 participants; moderate quality evidence) (28, 29) and femoral neck (MD -1.92, 95% CI -2.61 to -1.23; I² statistic = 34%; P < 0.001; three trials, 574 participants; moderate quality evidence) (28, 29) (Fig. 6, Table 2) compared to placebo.
There was no significant of severe, serious or adverse event led to discontinuation of elagolix treatment. Elagolix has increased the number of patients with side effect of hot flush (RR 7.47, 95% CI 4.99 to 11.18; I² statistic = 8%; P < 0.001; four trials, 890 participants; moderate quality evidence) (27–29) and headache (RR 1.88, 95% CI 1.25 to 2.83; I² statistic = 0%; P < 0.001; four trials, 890 participants; low quality evidence) (27–29) (Fig. 7, Table 4) compared to placebo.
Table 4
Summary of findings, including GRADE quality assessment for the comparison between elagolix and placebo by adverse events
Adverse event
|
No of trials
|
No of participants
|
Risk Ratio (RR)
|
95% Confidence interval (CI)
|
P value
|
Random effect; I2 statistic
|
GRADE quality
|
Any AE
|
4
|
890
|
1.25
|
1.15, 1.36
|
P < 0.001
|
0%
|
High
|
Serious AE
|
4
|
890
|
0.93
|
0.48, 1.81
|
P = 0.830
|
0%
|
Low
|
Severe AE
|
3
|
605
|
1.53
|
0.86, 2.73
|
P = 0.150
|
0%
|
Low
|
AE led to discontinuation
|
4
|
890
|
1.66
|
1.05, 2.64
|
P = 0.030
|
0%
|
Low
|
Hot flush
|
4
|
890
|
7.47
|
4.99, 11.18
|
P < 0.001
|
8%
|
Moderate
|
Headache
|
4
|
890
|
1.88
|
1.25, 2.83
|
P = 0.003
|
0%
|
Low
|
Abdominal pain
|
2
|
495
|
1.17
|
0.37, 3.66
|
P = 0.790
|
6%
|
Low
|
Dizziness
|
2
|
495
|
1.26
|
0.48, 3.29
|
P = 0.640
|
18%
|
Low
|
Nausea
|
4
|
890
|
1.00
|
0.53, 1.92
|
P = 0.990
|
41%
|
Low
|
Fatigue
|
4
|
890
|
0.77
|
0.33, 1.79
|
P = 0.550
|
0%
|
Low
|
Hypertension
|
2
|
495
|
1.25
|
0.14, 10.93
|
P = 0.840
|
*
|
Low
|
* Not estimable due to no hypertension events for both Elagolix and placebo. Carr et al, 2018.
|
B) Comparison between elagolix and elagolix with estradiol/norethindrone acetate
There was no difference in menstrual blood loss of less than 80 ml (RR 1.08, 95% CI 1.00 to 1.16; I² statistic = 56%; P = 0.070; five trials, 1365 participants; moderate quality evidence) (Fig. 8, Table 5) (27–30) or more than 50% reduction from baseline between the elagolix (RR 1.08, 95% CI 1.01 to 1.15; I² statistic = 43%; P = 0.020; five trials, 1365 participants; high quality evidence) (Fig. 9, Table 5) (27–30) and elagolix with estradiol/norethindrone acetate. The sensitivity analysis did not change the cumulative effect estimate. Table 6 showed the subgroup analysis for reduction of menstrual blood loss of less than 80 ml or more than 50% reduction from baseline stratified by dosage and uterine volume (Additional File 1).
Table 5
Summary of findings, including GRADE quality assessment for the comparison between elagolix and elagolix with estradiol/norethindrone acetate
Certainty assessment
|
No of patients
|
Effect
|
Certainty
|
No of studies
|
Study design
|
Risk of bias
|
Inconsistency
|
Indirectness
|
Imprecision
|
Other consideration
|
Elagolix
|
Elagolix with estradiol plus norethindrone acetate
|
Relative (95% CI)
|
Absolute (95% CI)
|
Reduction of menstrual blood loss less than 80 ml
|
5
|
Randomized trials
|
not serious
|
serious
|
not serious
|
not serious
|
none
|
393/459 (85.6%)
|
716/906 (79.0%)
|
RR 1.08
(1.00 to 1.16)
|
63 more per 1,000
(from 0 fewer to 126 more)
|
⨁⨁⨁◯
MODERATE
|
Reduction of more than 50% menstrual blood loss
|
5
|
Randomized trials
|
not serious
|
not serious
|
not serious
|
not serious
|
none
|
396/459 (86.3%)
|
722/906 (79.7%)
|
RR 1.08
(1.01 to 1.15)
|
64 more per 1,000
(from 8 more to 120 more)
|
⨁⨁⨁⨁
HIGH
|
Improvement in hemoglobin level
|
5
|
Randomized trials
|
not serious
|
serious
|
not serious
|
serious
|
none
|
206/319 (64.6%)
|
370/580 (63.8%)
|
RR 0.99
(0.80 to 1.22)
|
6 fewer per 1,000
(from 128 fewer to 140 more)
|
⨁⨁◯◯
LOW
|
Adverse event (Hot flush)
|
5
|
Randomized trials
|
not serious
|
not serious
|
not serious
|
serious a
|
none
|
258/474 (54.4%)
|
190/929 (20.5%)
|
RR 2.67
(2.30 to 3.10)
|
342 more per 1,000
(from 266 more to 429 more)
|
⨁⨁⨁◯
MODERATE
|
Uterine volume
|
5
|
Randomized trials
|
not serious
|
serious b
|
not serious
|
not serious
|
none
|
422
|
828
|
-
|
MD 17.47 lower
(27.54 lower to 7.4 lower)
|
⨁⨁⨁◯
MODERATE
|
Fibroid volume
|
5
|
Randomized trials
|
not serious
|
not serious
|
not serious
|
not serious
|
none
|
408
|
800
|
-
|
MD 23.18 lower
(28.98 lower to 17.38 lower)
|
⨁⨁⨁⨁
HIGH
|
Symptom severity
|
5
|
Randomized trials
|
not serious
|
not serious
|
not serious
|
not serious
|
none
|
429
|
859
|
-
|
MD 9.05 lower
(9.68 lower to 8.43 lower)
|
⨁⨁⨁⨁
HIGH
|
Health-related quality of life
|
5
|
Randomized trials
|
not serious
|
very serious c
|
not serious
|
not serious
|
none
|
428
|
859
|
-
|
MD 9.94 higher
(5.82 higher to 14.06 higher)
|
⨁⨁◯◯
LOW
|
Bone mineral density (Lumbar spine)
|
4
|
Randomized trials
|
Not serious
|
Not serious
|
Not serious
|
Serious
|
none
|
362
|
764
|
-
|
MD 2.63 lower (3.12 lower to 2.14 lower)
|
⨁⨁⨁◯
MODERATE
|
Bone mineral density (Total hip)
|
4
|
Randomized trials
|
Not serious
|
Not serious
|
Not serious
|
Serious
|
none
|
362
|
764
|
-
|
MD 1.93 lower (2.56 lower to 1.31 lower)
|
⨁◯◯◯
VERY LOW
|
Bone mineral density (Femoral neck)
|
4
|
Randomized trials
|
Not serious
|
Not serious
|
Not serious
|
Serious
|
none
|
362
|
764
|
-
|
MD 0.77 lower (1.84 lower t0 0.3 higher)
|
⨁◯◯◯
VERY LOW
|
Table 6
Summary of findings, including GRADE quality assessment for the comparison between elagolix and elagolix with estradiol/norethindrone acetate by subgroup analysis
Outcome/Subgroup
|
No of trials
|
No of participants
|
Risk Ratio (RR)
|
95% Confidence interval (CI)
|
P value
|
Random effect; I2 statistic
|
GRADE quality
|
Reduction of menstrual blood loss of less than 80 ml
|
Dosage of E2/NETA
|
0.5 mg E2/ 0.1 mg NETA
|
2
|
333
|
1.08
|
0.92, 1.27
|
P = 0.350
|
52%
|
Moderate
|
1.0 mg E2/ 0.5 mg NETA
|
4
|
1165
|
1.08
|
1.00, 1.18
|
P = 0.060
|
58%
|
Moderate
|
Uterine volume
|
< 500 cm3
|
3
|
894
|
1.07
|
0.95, 1.21
|
P = 0.250
|
70%
|
Low
|
> 500 cm3
|
2
|
471
|
1.08
|
0.94, 1.24
|
P = 0.290
|
46%
|
Moderate
|
Reduction of more than 50% menstrual blood loss
|
Dosage of E2/NETA
|
0.5 mg E2/ 0.1 mg NETA
|
2
|
333
|
1.10
|
1.01, 1.19
|
P = 0.020
|
0%
|
Moderate
|
1.0 mg E2/ 0.5 mg NETA
|
4
|
1165
|
1.08
|
0.99, 1.17
|
P = 0.070
|
56%
|
Moderate
|
Uterine volume
|
< 500 cm3
|
3
|
894
|
1.07
|
0.95, 1.21
|
P = 0.250
|
70%
|
Low
|
> 500 cm3
|
2
|
471
|
1.10
|
1.02, 1.17
|
P = 0.009
|
0%
|
Moderate
|
E2 - estradiol; NETA – norethindrone acetate
|
Foe secondary outcomes, there was no difference improvement in hemoglobin level between elagolix (RR 0.99, 95% CI 0.80 to 1.22; I² statistic = 68%; P = 0.930; five trials, 899 participants; low quality evidence) (27–30) and elagolix with estradiol/norethindrone acetate. However, elagolix has reduced mean percentage change in uterine volume (MD -17.47, 95% CI -27.54 to -7.40; I² statistic = 58%; P < 0.001; five trials, 1250 participants; moderate quality evidence) (27–30), fibroid volume (MD -23.18, 95% CI -28.98 to -17.38; I² statistic = 0%; P < 0.001; five trials, 1208 participants; high quality evidence) (27–30), symptoms severity (MD -9.05, 95% CI -9.68 to -8.43; I² statistic = 0%; P < 0.001; five trials, 1288 participants; high quality evidence) (27–30), and increased health-related quality of life (MD 9.94, 95% CI 5.82 to 14.06; I² statistic = 76%; P < 0.001; five trials, 1287 participants; low quality evidence) (27–30) (Additional File 1, Table 5) compared to elagolix with estradiol/norethindrone acetate.
Elagolix has reduced bone mineral density in the lumbar spine (MD -2.63, 95% CI -3.12 to -2.14; I² statistic = 49%; P < 0.001; four trials, 1126 participants; moderate quality evidence (28–30), and total hip (MD -1.93, 95% CI -2.56 to -1.31; I² statistic = 75%; P < 0.001; four trials, 1126 participants; very low quality evidence) (28–30) except femoral neck (MD -0.77, 95% CI -1.84 to 0.30; I² statistic = 78%; P = 0.160; four trials, 1126 participants; very low quality evidence) (28–30) (Fig. 10, Table 5) compared to elagolix with estradiol/norethindrone acetate.
There was no difference of severe, serious or adverse event led to discontinuation between elagolix treatment and elagolix with estradiol/norethindrone acetate. Elagolix has increased the number of patients with side effect of hot flush (RR 2.67, 95% CI 2.30 to 3.10; I² statistic = 0%; P < 0.001; five trials, 1403 participants; moderate quality evidence) (27–30), reduced the number of patients with risk of nausea (RR 0.63, 95% CI 0.43 to 0.91; I² statistic = 0%; P = 0.010; five trials, 1403 participants; low quality evidence) (27–30) and fatigue (RR 0.43, 95% CI 0.23 to 0.80; I² statistic = 0%; P = 0.008; five trials, 1403 participants; low quality evidence) (27–30) (Fig. 11, Table 7) compared to elagolix with estradiol/norethindrone acetate.
Table 7
Summary of findings, including GRADE quality assessment for comparison between elagolix and elagolix with estradiol/norethindrone acetate by adverse events
Adverse event
|
No of trials
|
No of participants
|
Risk Ratio (RR)
|
95% Confidence interval (CI)
|
P value
|
Random effect; I2 statistic
|
GRADE quality
|
Any AE
|
5
|
1403
|
1.13
|
1.03, 1.25
|
P = 0.010
|
68%
|
Moderate
|
Serious AE
|
5
|
1403
|
1.23
|
0.68, 2.24
|
P = 0.500
|
0%
|
Low
|
Severe AE
|
4
|
979
|
0.90
|
0.45, 1.83
|
P = 0.780
|
51%
|
Low
|
AE led to discontinuation
|
5
|
1403
|
1.31
|
0.92, 1.87
|
P = 0.130
|
0%
|
Low
|
Hot flush
|
5
|
1403
|
2.67
|
2.30, 3.10
|
P < 0.001
|
0%
|
Moderate
|
Headache
|
5
|
1403
|
1.16
|
0.84, 1.62
|
P = 0.370
|
22%
|
Low
|
Abdominal pain
|
2
|
493
|
1.02
|
0.14, 7.47
|
P = 0.990
|
47%
|
Low
|
Dizziness
|
2
|
493
|
0.87
|
0.38, 2.02
|
P = 0.750
|
0%
|
Low
|
Nausea
|
5
|
1403
|
0.63
|
0.43, 0.91
|
P = 0.010
|
0%
|
Low
|
Fatigue
|
5
|
1403
|
0.43
|
0.23, 0.80
|
P = 0.008
|
0%
|
Low
|
Hypertension
|
3
|
809
|
0.60
|
0.23, 1.59
|
P = 0.300
|
0%
|
Low
|