| Literature DB >> 28115839 |
David Price1, Anders Østrem2, Mike Thomas3, Tobias Welte4.
Abstract
Several fixed-dose combinations (FDCs) of long-acting bronchodilators (a long-acting muscarinic antagonist [LAMA] plus a long-acting β2-agonist [LABA]) are available for the treatment of COPD. Studies of these FDCs have demonstrated substantial improvements in lung function (forced expiratory volume in 1 second) in comparison with their respective constituent monocomponents. Improvements in patient-reported outcomes (PROs), such as symptoms and health status, as well as exacerbation rates, have been reported compared with a LABA or LAMA alone, but results are less consistent. The inconsistencies may in part be owing to differences in study design, methods used to assess study end points, and patient populations. Nevertheless, these observations tend to support an association between improvements in forced expiratory volume in 1 second and improvements in symptom-based outcomes. In order to assess the effects of FDCs on PROs and evaluate relationships between PROs and changes in lung function, we performed a systematic literature search of publications reporting randomized controlled trials of FDCs. Results of this literature search were independently assessed by two reviewers, with a third reviewer resolving any conflicting results. In total, 22 Phase III randomized controlled trials of FDC bronchodilators in COPD were identified, with an additional study including a post-literature search (ten for indacaterol-glycopyrronium once daily, eight for umeclidinium-vilanterol once daily, three for tiotropium-olodaterol once daily, and two for aclidinium-formoterol twice daily). Results from these studies demonstrated that the LAMA-LABA FDCs significantly improved lung function compared with their component monotherapies or other single-agent treatments. Furthermore, LABA-LAMA combinations also generally improved symptoms and health status versus monotherapies, although some discrepancies between lung function and PROs were observed. Overall, the safety profiles of the FDCs were similar to placebo. Further research is required to examine more closely any relationship between lung function and PROs in patients receiving LABA-LAMA combinations.Entities:
Keywords: chronic obstructive pulmonary disease; combination therapy; dyspnea; forced expiratory volume; health status; spirometry
Mesh:
Substances:
Year: 2016 PMID: 28115839 PMCID: PMC5221557 DOI: 10.2147/COPD.S116719
Source DB: PubMed Journal: Int J Chron Obstruct Pulmon Dis ISSN: 1176-9106
Figure 1Flowchart of systematic literature search.
Notes: Reasons for exclusion comprised: not a primary publication or not containing novel data from clinical studies, non-COPD study, data not from a randomized clinical study, medication not combination LABA–LAMA bronchodilator treatment, and unapproved dose for a licensed combination therapy.
Abbreviations: LABA, long-acting β2-agonist; LAMA, long-acting muscarinic antagonist.
Clinical trials of FDC bronchodilator therapies evaluating treatment effects on lung function and/or patient-reported outcome
| Reference and study | Design | Duration | Patients, n | Patient population | Mean FEV1% predicted (GOLD stage) | Treatment | Primary and other efficacy outcomes |
|---|---|---|---|---|---|---|---|
| Published Phase III clinical trials | |||||||
|
| |||||||
| Bateman et al | MC, R, DB | 26 weeks | 2,144 | Moderate-to-severe COPD (FEV1 ≥30% and <80% predicted) and symptomatic (total daily symptom score ≥1 on ≥4 of the 7 days prior to randomization); 75% had no reports of exacerbations in the previous year | 55 (II or III) | IND–GLY 110/50 µg Indacaterol 150 µg Glycopyrronium 50 µg Tiotropium 18 µg OL Placebo | Trough FEV1 at week 26 (primary) Dyspnea (TDI) Health status (SGRQ) Rescue-medication use Symptoms (diary) |
|
| |||||||
| Dahl et al | MC, R, DB | 52 weeks | 339 | Moderate-to-severe COPD (FEV1 ≥30% and <80% predicted) and symptomatic (total daily symptom score ≥1 on ≥4 of the 7 days prior to randomization); excluded patients who had an exacerbation requiring antibiotics, oral steroids, or hospitalization, within ≤6 weeks prior to screening or between screening and randomization | 57 (II or III) | IND–GLY 110/50 µg Placebo | Safety (primary) Rescue-medication use Symptoms (diary) Trough FEV1 |
|
| |||||||
| Dahl et al | MC, R, DB | 4 weeks | 193 | Moderate-to-severe COPD (FEV1 ≥30% and <80% predicted) and symptomatic (total daily symptom score ≥1 on ≥3 days prior to randomization); excluded patients who had an exacerbation requiring treatment with antibiotics and/or oral corticosteroids and/or hospitalization ≤6 weeks prior to visit 1 | 54 (II or III) | IND–GLY 110/50 µg Indacaterol 150 µg + glycopyrronium 50 µg | Trough FEV1 at week 4 (noninferiority; primary) Rescue-medication use Symptoms (diary) |
|
| |||||||
| Mahler et al | MC, R, B, DD, XO | 6 weeks | 247 | Moderate-to-severe COPD (FEV1 ≥30% and <80% predicted) with mMRC grade ≥2; 70% of patients had no history of exacerbations in the previous year | 56 (II or III) | IND–GLY 110/50 µg Placebo Tiotropium 18 µg | Dyspnea at week 6 (TDI-SAC; primary) FEV1 AUC0–4 h Rescue-medication use Symptoms (diary) |
| Vogelmeier et al | MC, R, DB, DD | 26 weeks | 523 | Moderate-to-severe COPD (FEV1 ≥40% and <80% predicted) and symptomatic (total daily symptom score ≥1 on ≥4 of the 7 days prior to randomization); excluded patients with exacerbations requiring treatment with antibiotics, systemic corticosteroids, and/or hospitalization in the previous year | 60 (II or III) | IND–GLY 110/50 µg SFC 50/500 µg BID | FEV1 AUC0–12 h at week 26 (primary) Dyspnea (TDI) FEV1 and FVC Health status (SGRQ) Rescue-medication use Symptoms (diary) |
|
| |||||||
| Wedzicha et al | MC, R, DB | 64 weeks | 2,224 | Severe-to-very-severe COPD (FEV1 <50% predicted) with ≥1 COPD exacerbation requiring treatment with systemic corticosteroids and/or antibiotics in the previous year | 37 (III or IV) | IND–GLY 110/50 µg Glycopyrronium 50 µg Tiotropium 18 µg OL | Exacerbations (primary) Health status (SGRQ) Rescue-medication use Trough FEV1 |
|
| |||||||
| Beeh et al | MC, R, DB, DD, XO | 3 weeks | 85 | Moderate-to-severe COPD (FEV1 ≥40% and <70% predicted); 83% of patients had no history of exacerbation in the previous year | 56 (II or III) | IND–GLY 110/50 µg Tiotropium 18 µg | Exercise endurance time at week 3 (primary) Dyspnea and leg discomfort (Borg) Lung function Rescue-medication use Symptoms (diary) |
|
| |||||||
| Buhl et al | DB, TD | 26 weeks | 934 | Moderate-to-severe COPD (FEV1 ≥30%–<80% predicted; postbronchodilator FEV1 to FVC ratio <0.7 at screening), current or ex-smoker (≥10 pack-years); no COPD exacerbation within 6 weeks of prescreening or prior to randomization | 53 (II or III) | IND–GLY 110/50 µg Tiotropium 18 µg + formoterol 12 µg BID | Health status (SGRQ-C; primary) Dyspnea (TDI) Symptoms (SGRQ-C) FEV1 and FVC Exacerbations |
|
| |||||||
| Zhong et al | MC, R, DB, DD | 26 weeks | 744 | Moderate-to-severe COPD (FEV1 ≥30%–<80% predicted; postbronchodilator FEV1to FVC ratio <0.7 at screening), current or ex-smoker (≥10 pack-years); mMRC grade ≥2; ≤1 COPD exacerbation within 12 months of screening/randomization | 52 (II or III) | IND–GLY 110/50 µg SFC 50/500 µg BID | Trough FEV1 at week 26 (primary) Other FEV1, FVC Dyspnea (TDI) Health status (SGRQ and CAT) Rescue-medication use Symptoms (diary) Exacerbations |
|
| |||||||
| Wedzicha et al | MC, R, DB, DD, NI | 52 weeks | 3,362 | Moderate-to-very-severe COPD (FEV1 ≥25%–<60% predicted; postbronchodilator FEV1 to FVC ratio <0.7 at screening); mMRC grade ≥2; a documented history of ≥1 COPD exacerbation requiring treatment with systemic corticosteroids and/or antibiotics) in the previous 1 year | 44 (II–IV) | IND–GLY 110/50 µg | Exacerbations (primary) |
|
| |||||||
| Donohue et al | MC, R, DB | 24 weeks | 1,536 | Moderate-to-very-severe COPD (FEV1 ≤70% predicted) and mMRC grade ≥2; exacerbation history not stated | 47 (II–IV) | UMEC–VI 62.5/25 µgUmeclidinium 62.5 µg | Trough FEV1 at week 24 (primary) |
|
| |||||||
| Decramer et al | MC, R, B, DD | 24 weeks | 843 | Moderate-to-very-severe COPD (FEV1 ≤70% predicted) and mMRC grade ≥2; 53% of patients experienced an exacerbation in the previous year | 48 (II–IV) | UMEC–VI 125/25 µg | Trough FEV1 at week 24 (primary) |
|
| |||||||
| Decramer et al | MC, R, B, DD | 24 weeks | 869 | Moderate-to-very-severe COPD (FEV1 ≤70% predicted) and mMRC grade ≥2; 38% of patients had experienced an exacerbation in the previous year | 47 (II–IV) | UMEC–VI 125/25 µg | Trough FEV1 at week 24 (primary) |
|
| |||||||
| Maleki-Yazdiet al | MC, R, B, DD | 24 weeks | 905 | Moderate-to-very-severe COPD (FEV1 ≤70% predicted) and mMRC grade ≥2; exacerbation history not stated | 46 (II–IV) | UMEC–VI 62.5/25 µg | Trough FEV1 at week 24 (primary) |
|
| |||||||
| Maltais et al | MC, R, DB, XO | 12 weeks | 349 | Moderate-to-severe COPD (FEV1 ≥35% and ≤70% predicted), mMRC grade ≥2 and FRC ≥120% (hyperinflated); exacerbation history not stated | 51 (II or III) | UMEC–VI 125/25 or 62.5/25 µg | Exercise-endurance time at week 12 (co-primary) |
|
| |||||||
| Maltais et al | MC, R, DB, XO | 12 weeks | 308 | Moderate-to-severe COPD (FEV1 ≥35% and ≤70% predicted), mMRC grade ≥2 and FRC ≥120% (hyperinflated); exacerbation history not stated | 51 (II or III) | UMEC–VI 125/25 or 62.5/25 µg | Exercise-endurance time at week 12 (coprimary) |
|
| |||||||
| Donohue et al | MC, R, DB, DD | 12 weeks | 707 | Moderate-to-severe COPD; (FEV1 ≥30% and ≤70% predicted); no exacerbations in past year | 49–50 (II or III) | UMEC–VI 62.5/25 µg | FEV1 0–24 hours at week 12 (primary) |
|
| |||||||
| Donohue et al | MC, R, DB, DD | 12 weeks | 700 | Moderate-to-severe COPD; (FEV1 ≥30% and ≤70% predicted); no exacerbations in past year | 49–50 (II or III) | UMEC–VI 62.5/25 µg | FEV1 0–24 hours at week 12 (primary) |
|
| |||||||
| Buhl et al | MC, R, DB | 52 weeks (×2) | 2,624 | Moderate-to-severe COPD (GOLD stage II–III); FEV1 ≥30% and <80% predicted; exacerbation history not stated | 49–50 (I–IV) | Olodaterol 5 µg | FEV1 0–3 hours, trough FEV1 and health status (SGRQ total score) at week 24 (joint primary) |
|
| |||||||
| Beeh et al | MC, R, DB, IN, XO | 6 weeks | 219 | Moderate-to-very-severe COPD (GOLD stage II–IV); FEV1 <80% predicted (≥30% for certain sites); exacerbation history not stated | Olodaterol 5 µg | FEV1 AUC0–24 h at week 6 (primary) | |
|
| |||||||
| Singh et al | MC, R, DB | 24 weeks | 1,729 | Moderate-to-severe COPD (FEV1 ≥30%, but <80% predicted); exacerbation history not stated | 54 (III–IV) | Placebo ACL–FORM 400/12 µg BID ACL–FORM 400/6 µg BID Aclidinium 400 µg BID Formoterol 12 µg BID | FEV1 1 hour postdose (co-primary) |
|
| |||||||
| D’Urzo et al | MC, R, DB | 24 weeks | 1,692 | Moderate-to-severe COPD (FEV1 ≥30% and <80% predicted); excluded patients with exacerbations ≤6 weeks (≤3 months if hospitalized for exacerbation) before screening | 53–55 (III–IV) | Placebo | FEV1 hour postdose (coprimary) |
Notes: Treatment was once daily unless stated otherwise.
Patients randomized to treatment;
investigator-blinded only;
inclusion criteria: FEV1 ≤70% predicted and FEV1/FVC 0.7.
Abbreviations: ACL–FORM, aclidinium–formoterol; AUC0–4 h, area under the (plasma concentration–time) curve from 0 to 4 hours; AUC0–12 h, area under the (plasma concentration–time) curve from 0 to 12 hours; AUC0–24 h, area under the (plasma concentration–time) curve from 0 to 24 hours; B, blinded; BID, bis in die (twice daily); CAT, COPD Assessment Test; DB, double-blind; DD, double-dummy; DPI, dry-powder inhaler; E-RS, Evaluating Respiratory Symptoms; EXACT, EXAcerbations of COPD Tool; FEV1, forced expiratory volume in 1 second; FRC, functional residual capacity; FVC, forced vital capacity; GFF, glycopyrrolate–formoterol fumarate; GOLD, Global Initiative For Chronic Obstructive Lung Disease; HCRU, health care-resource utilization; IC, inspiratory capacity; IN, incomplete; IND–GLY, indacaterol–glycopyrronium; MC, multicenter; MDI, metered-dose inhaler; mMRC, modified Medical Research Council; NI, noninferiority; NR, not reported; OL, open-label; PEFR, peak expiratory flow rate; R, randomized; SFC, salmeterol–fluticasone combination; SOBDA, Shortness Of Breath with Daily Activity; SGRQ-C, St George’s Respiratory Questionnaire – COPD; TD, triple-dummy; TDI-SAC, transition dyspnea index – self-administered, computerized; TIO–OLO, tiotropium–olodaterol; UMEC–VI, umeclidinium–vilanterol; XO, crossover.
Lung function: margin of efficacy of fixed combinations versus comparators in fully published studies
| Reference and study | Duration | Treatment | Trough FEV1 LSM (95% CI) treatment difference at end point, mL | Other lung-function parameters |
|---|---|---|---|---|
| Bateman et al | 26 weeks | IND–GLY 110/50 µg OD vs Indacaterol 150 µg OD | IND–GLY provided significantly higher FEV1 AUC0–4 h and peak FEV1 compared with placebo, glycopyrronium, and tiotropium (all | |
| 70 | ||||
| 80 | ||||
| 70 | ||||
| 200 | ||||
|
| ||||
| Dahl et al | 52 weeks | IND–GLY 110/50 µg OD vs placebo | FEV1 at 60 minutes postdose significantly greater with IND–GLY than placebo throughout the 52-week treatment period ( | |
| 189 | ||||
|
| ||||
| Dahl et al | 4 weeks | IND–GLY 110/50 µg OD vs indacaterol 150 µg OD + glycopyrronium 50 µg OD | FEV1 AUC0–4 h (day 1 and week 4) similar between treatment groups | |
| 5 (NR; NS for superiority) | ||||
|
| ||||
| Mahler et al | 6 weeks | IND–GLY 110/50 µg OD vs Placebo | FEV1 AUC0–4 h postdose significantly higher for IND–GLY vs tiotropium and placebo at day 1 and week 6 (all | |
| 330 (0.31–0.36) | ||||
| 110 (0.08–0.13) | ||||
|
| ||||
| Vogelmeier et al | 26 weeks | IND–GLY 110/50 µg OD vs SFC 50/500 µg BID | Week 26 FEV1 AUC0–12 h significantly higher with IND–GLY than with SFC (treatment difference 138 mL, 95% CI 0.1–0.176; | |
| 103 | ||||
|
| ||||
| Wedzicha et al | 64 weeks | IND–GLY 110/50 µg OD vs Glycopyrronium 50 µg OD | Weeks 4–64: | NR |
| 70–80 | ||||
| 60–80 | ||||
|
| ||||
| Beeh et al | 3 weeks | IND–GLY 110/50 µg OD vs Tiotropium 18 µg OD | At day 21, mean treatment differences in trough IC, FEV1, and FVC significantly higher for IND–GLY vs placebo (190, 200, and 280 mL, respectively) and vs tiotropium (150, 100, and 110 mL, respectively) | |
| 100 | ||||
| 200 | ||||
|
| ||||
| Buhl et al | 26 weeks | IND/GLY 110/50 µg OD vs tiotropium 18 µg OD + formoterol 12 µg BID | IND–GLY increased predose FVC vs tiotropium + formoterol at week 26 (74 mL, 95% CI: 24–125 mL; | |
| 68 | ||||
|
| ||||
| Zhong et al | 26 weeks | IND–GLY 110/50 µg OD vs SFC 50/500 µg BID | Improvements in trough FEV1 with IND–GLY vs SFC observed at day 1 (Δ=43 mL) and reaching steady state by week 12 (Δ=78 mL, both | |
| 72 | ||||
|
| ||||
| Wedzicha et al | 52 weeks | IND–GLY 110/50 µg OD vs SFC 50/500 µg BID | Change from baseline in FEV1 AUC0–12h (measured in a subgroup of 556 patients) was significantly greater with IND–GLY vs SFC at week 52 (Δ=110 mL, | |
| 62 | ||||
|
| ||||
| Donohue et al | 24 weeks | UMEC–VI 62.5/25 µg OD vs Umeclidinium 62.5 µg OD | Change from baseline: | Improvements in trough FVC change from baseline observed at day 169 for UMEC–VI 62.5/25 µg, UMEC 62.5 µg, and VI 25 µg vs placebo (248 mL, 175 mL, and 105 mL; all |
| 52 | ||||
| 95 | ||||
| 167 | ||||
|
| ||||
| Decramer et al | 24 weeks | UMEC–VI 125/25 µg OD | Change from baseline: | Mean 0- to 6-hour FEV1 on day 168 for UMEC–VI (both doses) significantly improved vs tiotropium 18 µg |
| 90 | ||||
| 90 | ||||
|
| ||||
| Decramer et al | 24 weeks | UMEC–VI 125/25 µg OD | Change from baseline: | Mean 0- to 6-hour FEV1 on day 168 for both doses of UMEC/VI improved vs tiotropium 18 µg (nominal |
| 60 | ||||
| 22 (-27 to 72) | ||||
|
| ||||
| Maleki-Yazdi et al | 24 weeks | UMEC–VI 62.5/25 µg OD vs tiotropium 18 µg OD | Change from baseline: | Weighted mean FEV1 over 0–6 hours postdose at day 168 improved for UMEC–VI vs tiotropium (105 mL, 95% CI 0.071–0.14; |
| 112 | ||||
|
| ||||
| Maltais et al | 12 weeks | UMEC–VI 125/25 µg OD | Change from baseline vs placebo: | Trough FEV1 numerically improved with UMEC–VI 125/25 µg and UMEC–VI 62.5/25 µg compared with placebo from day 2 to week 12 |
| 211 | ||||
| 87 | ||||
| 140 | ||||
| 99 | ||||
|
| ||||
| Maltais et al | 12 weeks | UMEC–VI 125/25 µg OD | Change from baseline vs placebo: | Trough FEV1 improved with UMEC–VI 125/25 µg and UMEC–VI 62.5/25 µg compared with placebo ( |
| 243 | ||||
| 144 | ||||
| 255 | ||||
| 112 | ||||
|
| ||||
| Donohue et al | 12 weeks | UMEC–VI 62.5/25 µg OD vs SFC 50/250 µg BID | Change from baseline: | FEV1 significantly improved for UMEC–VI vs SFC at all time points on day 84 (except 18 hours); significantly greater improvement in LSM trough FEV1 from baseline for UMEC–VI vs SFC on day 85 (treatment difference 82 mL, |
| 74 | ||||
|
| ||||
| Donohue et al | 12 weeks | UMEC–VI 62.5/25 µg OD vs SFC 50/250 µg BID | Change from baseline: | FEV1 significantly improved for UMEC–VI vs SFC at all time points on day 84; significantly greater improvement in LSM trough FEV1 from baseline for UMEC–VI vs SFC on day 85 (treatment difference 98 mL, |
| 101 | ||||
|
| ||||
| Buhl et al | 52 weeks | TIO–OLO 2.5/5 µg OD | Change from baseline | Improvements observed for FEV1 values on all test days over each of the 52-week studies; responses in trough FVC and FVC AUC0–3 h over 24 weeks consistent with the primary end points |
| at week 24: | ||||
| 82 | ||||
| 71 | ||||
| NR | ||||
|
| ||||
| Buhl et al | 52 weeks | TIO–OLO 2.5/5 µg OD | Change from baseline | Improvements observed for FEV1 values on all test days over each of the 52-week studies; responses in trough FVC and FVC AUC0–3 h over 24 weeks consistent with the primary end points |
| at week 24: | ||||
| 88 | ||||
| 50 | ||||
| NR | ||||
|
| ||||
| Beeh et al | 6 weeks | TIO–OLO 2.5/5 µg OD | Adjusted mean difference: | Significant improvement in FEV1 AUC0–24 h and greater improvement in 24-hour FEV1 profile for both TIO–OLO doses vs placebo and monotherapies at 6 weeks; similar pattern of response for FVC, FRC, and residual volume |
| 92 | ||||
| 79 | ||||
| NR | ||||
| 207 | ||||
|
| ||||
| Singh et al | 24 weeks | ACL–FORM 400/6 µg BID | Change from baseline at week 24: | Fast onset of action of both ACL–FORM doses on day 1, with significant improvements in bronchodilation vs placebo at 5 minutes postdose |
| 85 | ||||
| ~25 | ||||
| 143 | ||||
|
| ||||
| D’Urzo et al | 24 weeks | ACL–FORM 400/6 µg BID | Change from baseline at week 24: | ACL–FORM (both doses) associated with significant changes from baseline in peak FEV1 at day 1 and week 24 ( |
| 45 | ||||
| 28 | ||||
| 129 | ||||
Notes: Treatment once daily unless stated otherwise.
Significant treatment difference;
FEV1 AUC0–4 h;
dose not approved for use (ACL–FORM, dose not approved in EU);
estimated from figure.
Abbreviations: ACL–FORM, aclidinium–formoterol; AUC0–3 h, area under the plasma concentration-time curve from 0 to 3 hours; AUC0–4 h, area under the (plasma concentration–time) curve from 0 to 4 hours; AUC0–12 h, area under the (plasma concentration–time) curve from 0 to 12 hours; AUC0–24 h, area under the (plasma concentration–time) curve from 0 to 24 hours; BID, bis in die (twice daily); CI, confidence interval; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; FRC, functional residual capacity; IC, inspiratory capacity; IND–GLY, indacaterol–glycopyrronium; LSM, least-squares mean; NR, not reported; NS, not significant; OD, once daily; OL, open-label; SFC, salmeterol/fluticasone combination; TIO–OLO, tiotropium–olodaterol; UMEC–VI, umeclidinium–vilanterol.
Symptoms: margin of efficacy of fixed combinations versus comparators in published studies
| Reference and study | Duration | Treatment | Treatment difference at end point
| ||
|---|---|---|---|---|---|
| TDI total score, LSM (95% CI) | % TDI responders | Other | |||
| Bateman et al | 26 weeks | IND–GLY 110/50 µg OD vs Indacaterol 150 µg OD | Diary data (values vs placebo): % days with no daytime symptoms, +3.05 | ||
| 0.25 (NR) | 3.5 (NR) | ||||
| 0.20 (NR) | 4.4 (NR) | ||||
| 0.51 | 8.9 | ||||
| 1.09 | 10.6 | ||||
|
| |||||
| Dahl et al | 52 weeks | IND–GLY 110/50 µg OD vs Placebo | Diary data: | ||
| NR | NR | Total daily symptom score, −0.573 | |||
|
| |||||
| Dahl et al | 4 weeks | IND–GLY 110/50 µg OD vs indacaterol 150 µg OD + glycopyrronium 50 µg OD | Diary data: | ||
| NR | NR | Total daily symptom score, 0.07 (−0.24, 0.39) | |||
|
| |||||
| Mahler et al | 6 weeks | IND–GLY 110/50 µg OD vs tiotropium 18 µg OD | SAC TDI: | SAC TDI: | Diary data (vs placebo and tiotropium): |
| 0.49 | 11.5 | Total daily symptom score, −0.72 | |||
| 1.37 | 17.8 | ||||
|
| |||||
| Vogelmeier et al | 26 weeks | IND–GLY 110/50 µg OD vs SFC 50/500 µg BID | Diary data: | ||
| 0.76 | 10.7 | Differences in scores for most symptoms NS between treatment groups | |||
|
| |||||
| Beeh et al | 3 weeks | IND–GLY 110/50 µg OD vs tiotropium 18 µg OD | Diary data, mean daily symptom score vs baseline: | ||
| NR | NR | ||||
| NR | NR | ||||
|
| |||||
| Buhl et al | 26 weeks | IND–GLY 110/50 µg OD vs tiotropium 18 µg OD + formoterol 12 µg BID | LSM treatment difference in SGRQ-C symptom score IND–GLY vs tiotropium + formoterol (−1.31 [95% CI −3.49, 0.86]) | ||
| 0.38 (−0.06, 0.82) | 7.2 (1.17 risk ratio) | ||||
|
| |||||
| Zhong et al | 26 weeks | IND–GLY 110/50 µg OD vs SFC 50/500 µg BID | Improvements in TDI focal score at weeks 12 and 26 similar between IND–GLY and SFC | ||
| 0.25 (−0.09, 0.59) | NR | ||||
|
| |||||
| Donohue et al | 24 weeks | UMEC–VI 62.5/25 µg OD vs umeclidinium 62.5 µg OD | NR | ||
| 0.3 (−0.2, 0.7) | 5.0 (NR) | ||||
| 0.4 (−1.0, 0.8) | 7.0 | ||||
| 1.2 | 17.0 | ||||
|
| |||||
| Decramer et al | 24 weeks | UMEC–VI 125/25 µg OD | |||
| NR | |||||
| −0.1 (−0.7, 0.5) | 5 (0.9) | ||||
| 0.2 (−0.4, 0.8) | 6 (1.4) | ||||
|
| |||||
| Decramer et al | 24 weeks | UMEC–VI 125/25 µg OD | |||
| 0.2 (−0.5, 0.9) | 6 (1.3) | NR | |||
| 0.4 (−0.3, 1.1) | 7 (1.3) | ||||
|
| |||||
| Donohue et al | 12 weeks | UMEC–VI 62.5/25 µg OD vs SFC 50/250 µg BID | |||
| 0.3 (−0.2, 0.7) | NR | NR | |||
|
| |||||
| Donohue et al | 12 weeks | UMEC–VI 62.5/25 µg OD vs SFC 50/250 µg BID | |||
| 0.3 (−0.1, 0.8) | NR | NR | |||
|
| |||||
| Maltais et al | 12 weeks | Exercise dyspnea scale (Borg), changes from baseline vs placebo: | |||
| UMEC–VI 125/25 µg OD | −0.25 (−0.57 to 0.07) | ||||
| −0.05 (−0.37 to 0.27) | |||||
| NR | NR | −0.16 (−0.61 to 0.3) | |||
| NR | NR | −0.13 (−0.58 to 0.33) | |||
| NR | NR | 0.39 (−0.01 to 0.79) | |||
|
| |||||
| Maltais et al | 12 weeks | Exercise dyspnea scale (Borg), change from baseline vs placebo: | |||
| UMEC–VI 125/25 µg OD | −0.34 (−0.76 to 0.03) | ||||
| −0.36 (0.67 to −0.05) | |||||
| NR | NR | −0.32 (−0.78 to 0.13) | |||
| NR | NR | −0.66 (−1.14 to −0.18) | |||
| NR | NR | −0.36 (−0.76 to 0.03) | |||
|
| |||||
| Buhl et al | 52 weeks | TIO–OLO 2.5/5 µg OD | (At week 24): | ||
| 0.420 | NR | NR | |||
| Tiotropium 5 µg OD | 0.356 | NR | NR | ||
|
| |||||
| Singh et al | 24 weeks | ACL–FORM 400/6 µg BID | E-RS changes from baseline: | ||
| 0.45 (0–0.9) | 3.5 (1.19) | −0.69 (−6.2) | |||
| 0.40 (−0.05 to 0.85) | 8.3 (1.42) | −0.89 (−8.4) | |||
| Placebo | 1.29 | 19.3 (2.54) | −0.82 (−8.2) | ||
|
| |||||
| ACL–FORM 400/12 µg BID vs Formoterol 12 µg BID | Nighttime symptoms, change from baseline: | ||||
| NR | NR | −0.04 (−4.2) | |||
| NR | NR | −0.09 | |||
| NR | NR | −0.07 (−8) | |||
|
| |||||
| ACL–FORM 400/12 µg BID vs Formoterol 12 µg BID | Early morning symptoms, change from baseline vs: | ||||
| NR | NR | −0.04 (−3.7) | |||
| NR | NR | −0.08 (−7.5) | |||
| NR | NR | −0.09 (−8.1) | |||
|
| |||||
| D’Urzo et al | 24 weeks | ACL–FORM 400/6 µg BID | E-RS changes from baseline: | ||
| 0.5 | 6.4 | −0.48 (−3.4) | |||
| 0.46 | 3.3 | −0.32 (−1.7) | |||
| 1.44 | 21.5 (2.8) | −1.36 (−10.8) | |||
|
| |||||
| ACL–FORM 400/6 µg BID | Night-time symptoms, change from baseline vs: | ||||
| NR | NR | −0.05 (−2.4) | |||
| NR | NR | −0.08 (−5.3) | |||
| NR | NR | −0.12 (−9.3) | |||
|
| |||||
| ACL–FORM 400/6 µg BID | Early-morning symptoms, change from baseline vs: | ||||
| NR | NR | −0.06 (−4.6) | |||
| NR | NR | −0.09 (−7.4) | |||
| NR | NR | −0.13 (−9.8) | |||
Notes: Treatment once daily unless stated otherwise.
TDI responders had improvement ≥1 unit in TDI score.
Significant treatment difference. Significant treatment difference versus
indacaterol,
glycopyrronium or
tiotropium (values NR).
Dose not approved for use (ACL–FORM, dose not approved in EU).
Values in parentheses are differences expressed in percentage points (not percentage differences).
Abbreviations: ACL–FORM, aclidinium–formoterol; BID, bis in die (twice daily); CI, confidence interval; E-RS, Evaluating Respiratory Symptoms; IND–GLY, indacaterol–glycopyrronium; LSM, least-squares mean; NR, not reported; NS, not significant; OR, odds ratio; SAC, self-administered, computerized; SFC, salmeterol–fluticasone combination; SGRQ-C, St George’s Respiratory Questionnaire – COPD; TIO–OLO, tiotropium–olodaterol; TDI, transition dyspnea index; UMEC–VI, umeclidinium–vilanterol.
Figure 2Differences between monotherapy and combination bronchodilators or placebo in TDI patient-response rates in published studies.
Notes: (A) Indacaterol–glycopyrronium; (B) umeclidinium–vilanterol 62.5/25 µg; (C) aclidinium–formoterol 400/12 µg BID. TDI response was defined as improvement of ≥1 unit in TDI score. All treatments were once daily unless stated otherwise. *Significant treatment difference. aBateman et al;2 bself-administered computerized TDI;38 cVogelmeier et al;39 dBuhl et al;25 eDonohue et al;41 fDecramer et al;23 gSingh et al;28 hD’Urzo et al.29
Abbreviations: BID, bis in die (twice daily); SFC, salmeterol–fluticasone propionate; TDI, transition dyspnea index.
Rescue-medication use: margin of efficacy of fixed combinations versus comparators in published studies
| Reference and study | Duration | Treatment | Rescue albuterol/salbutamol puffs/day change from baseline, LSM (95% CI) treatment difference at end point |
|---|---|---|---|
| Bateman et al | 26 weeks | IND–GLY 110/50 µg OD vs Indacaterol 150 µg OD | |
| −0.31 | |||
| −0.66 | |||
| −0.55 | |||
| −0.96 | |||
|
| |||
| Dahl et al | 52 weeks | IND–GLY 110/50 µg OD vs Placebo | |
| −0.73 | |||
|
| |||
| Dahl et al | 4 weeks | IND–GLY 110/50 µg OD vs Indacaterol 150 µg OD + glycopyrronium 50 µg OD | |
| −0.04 (−0.35 to 0.28) | |||
|
| |||
| Mahler et al | 6 weeks | IND–GLY 110/50 µg OD vs Placebo | |
| −1.43 | |||
| −0.45 | |||
|
| |||
| Vogelmeier et al | 26 weeks | IND–GLY 110/50 µg OD vs SFC 50/500 µg BID | |
| −0.39 | |||
|
| |||
| Wedzicha et al | 64 weeks | IND–GLY 110/50 µg OD vs Glycopyrronium 50 µg OD | |
| −0.81 | |||
| −0.76 | |||
|
| |||
| Beeh et al | 3 weeks | IND–GLY 110/50 µg OD vs Tiotropium 18 µg | |
| −1.08 | |||
| −1.23 | |||
|
| |||
| Zhong et al | 26 weeks | IND–GLY 110/50 µg OD vs SFC 50/500 µg BID | |
| −0.03 (−0.26 to 0.21) | |||
|
| |||
| Wedzicha et al | 52 weeks | IND–GLY 110/50 µg OD vs SFC 50/500 µg BID | |
| −0.25 | |||
|
| |||
| Donohue et al | 24 weeks | UMEC–VI 62.5/25 µg OD vs Umeclidinium 62.5 µg OD | |
| −0.6 | |||
| 0.1 (−0.3 to 0.5) | |||
| −0.8 | |||
|
| |||
| Decramer et al | 24 weeks | UMEC–VI 125/25 µg OD | |
| −0.7 | |||
| −0.3 (−0.8 to 0.3) | |||
|
| |||
| Decramer et al | 24 weeks | UMEC–VI 125/25 µg OD | |
| −0.6 (−1.2 to 0) | |||
| −0.6 (−1.2 to 0) | |||
|
| |||
| Maleki-Yazdi et al | 24 weeks | UMEC–VI 62.5/25 µg OD vs Tiotropium 18 µg OD | |
| −0.5 | |||
|
| |||
| Maltais et al | 12 weeks | UMEC–VI 125/25 µg OD | Differences from placebo: |
| −0.6 | |||
| −0.2 (−0.6 to 0.1) | |||
| −0.6 | |||
| −0.4 | |||
|
| |||
| Maltais et al | 12 weeks | UMEC–VI 125/25 µg OD | Differences from placebo: |
| −1.2 | |||
| −0.7 | |||
| −1.0 | |||
| −0.8 | |||
|
| |||
| Donohue et al | 12 weeks | UMEC–VI 62.5/25 µg OD vs SFC 50/250 µg BID | |
| 0 (−0.3 to 0.2) | |||
|
| |||
| Donohue et al | 12 weeks | UMEC–VI 62.5/25 µg OD vs SFC 50/250 µg BID | |
| −0.3 | |||
|
| |||
| Buhl et al | 52 weeks | TIO–OLO 2.5/5 µg OD | |
| ~ −0.4 | |||
| ~ −0.8 | |||
|
| |||
| Singh et al | 24 weeks | ACL–FORM 400/6 µg BID | |
| NS | |||
| Value NR | |||
| −0.66 | |||
|
| |||
| D’Urzo et al | 24 weeks | ACL–FORM 400/6 µg BID | |
| 0.21 | |||
| 0.43 | |||
| Value NR | |||
Notes: Treatment once daily unless stated otherwise.
Significant treatment difference;
dose not approved for use;
estimated from figure. Statistical analysis not reported.
Abbreviations: ACL–FORM, aclidinium–formoterol; BID, bis in die (twice daily); CI, confidence interval; IND–GLY, indacaterol–glycopyrronium; LSM, least-squares mean; NR, not reported; NS, not significant; OL, open-label; SFC, salmeterol–fluticasone combination; TIO–OLO, tiotropium–olodaterol; UMEC–VI, umeclidinium–vilanterol.
Exacerbations: margin of efficacy of fixed combinations versus comparators in published studies that included exacerbations as an efficacy outcome
| Reference and study | Duration | Treatment | Exacerbation definition | Treatment difference at end point
| |
|---|---|---|---|---|---|
| Exacerbation rate, RR (95% CI) | Time to first exacerbation, HR (95% CI) | ||||
| Wedzicha et al | 64 weeks | IND–GLY 110/50 μg OD vs Glycopyrronium 50 μg OD | Presence of two major symptoms (dyspnea, sputum volume, sputum purulence) for ≥2 consecutive days or worsening of one major symptom plus increase in one minor symptom (sore throat, colds, fever without other cause, cough, wheeze) for ≥2 consecutive days | ||
| 0.85 | 0.79 | ||||
| 0.86 | 1.13 | ||||
|
| |||||
| Buhl et al | 26 weeks | IND–GLY 110/50 μg OD vs tiotropium 18 μg OD + formoterol 12 μg BID | Moderate exacerbations were those managed with antibiotics and/or systemic corticosteroids; severe exacerbations were those that resulted in hospitalization | ||
| 0.85 (0.62–1.17) | NR | ||||
|
| |||||
| Zhong et al | 26 weeks | IND–GLY 110/50 μg OD vs SFC 50/500 μg BID | An exacerbation was considered moderate if patients were treated with systemic corticosteroids, antibiotics, or both. Exacerbations were considered severe if patients were hospitalized or experienced an emergency room visit ≥24 hours | ||
| 0.69 | 0.32 (0.12–0.88) | ||||
|
| |||||
| Wedzicha et al | 52 weeks | IND–GLY 110/50 μg OD vs SFC 50/500 μg BID | COPD exacerbations were categorized as mild (involving worsening of symptoms for >2 consecutive days, but not leading to treatment with systemic glucocorticoids or antibiotics), moderate (leading to treatment with systemic glucocorticoids, antibiotics, or both), or severe (leading to hospital admission or a visit to the ER that lasted >24 hours, in addition to treatment with systemic glucocorticoids, antibiotics, or both) | ||
| 0.89 | 0.84 | ||||
|
| |||||
| Donohue et al | 24 weeks | UMEC–VI 62.5/25 μg OD vs Umeclidinium 62.5 μg OD | Acute worsening of COPD symptoms requiring emergency treatment, hospitalization, or use of additional pharmacotherapy beyond study drug or rescue salbutamol (eg, oral steroids and antibiotics) | ||
| NR | NR | ||||
| NR | NR | ||||
| NR | 0.5 | ||||
|
| |||||
| Decramer et al | 24 weeks | UMEC–VI 125/25 μg OD | Acute worsening of COPD symptoms requiring use of any treatment other than study drug or rescue salbutamol | ||
| NR | 1.2 (0.5–2.6) | ||||
| NR | 0.7 (0.4–1.5) | ||||
|
| |||||
| Decramer et al | 24 weeks | UMEC–VI 125/25 μg OD | Acute worsening of COPD symptoms requiring use of any treatment other than study drug or rescue salbutamol | ||
| NR | 1.9 (1–3.6) | ||||
| NR | 1 (0.6–1.8) | ||||
|
| |||||
| Maleki-Yazdi et al | 24 weeks | UMEC–VI 62.5/25 μg OD vs tiotropium 18 μg OD | Acute worsening of COPD symptoms requiring use of any treatment other than study drug or rescue albuterol/salbutamol | ||
| NR | 0.5 | ||||
|
| |||||
| Buhl et al | 52 weeks | TIO–OLO 2.5/5 μg OD | “Moderate/severe” (not defined) | Kaplan–Meier plot shows descending probability in the following order: olodaterol 5 μg; tiotropium 2.5 μg; tiotropium 5 μg; | |
| NR | |||||
| NR | |||||
|
| |||||
| Singh et al | 24 weeks | ACL–FORM 400/6 μg BID | HCRU: an increase of COPD symptoms during ≥2 consecutive days that requires a change in COPD treatment | ||
| 0.64 (0.4–1) | NR | ||||
| 0.89 (0.6–1.4) | NR | ||||
| 0.73 (0.4–1.2) | NR | ||||
|
| |||||
| ACL–FORM 400/6 μg BID | EXACT: an increase from baseline in total EXACT score ≥9 points for ≥3 days or ≥12 points for ≥2 days | ||||
| 0.86 (0.7–1.1) | NR | ||||
| 0.78 (0.6–1) | NR | ||||
| 0.71 | NR | ||||
Notes: Treatment once daily unless stated otherwise.
Significant treatment difference;
data reported for all exacerbations;
includes only severe exacerbations requiring hospitalization/emergency room treatment for ≥24 hours;
dose not approved for use (ACL–FORM dose not approved in EU);
the EXACT instrument assesses patients’ breathlessness, cough and sputum, chest symptoms, difficulty bringing up sputum, feeling tired or weak, sleep disturbance, and feeling scared or worried about their condition with a 14-item questionnaire.
Abbreviations: ACL–FORM, aclidinium–formoterol; BID, bis in die (twice daily); CI, confidence interval; EXACT, EXAcerbations of COPD Tool; HCRU, health care-resource utilization; HR, hazard ratio; IND–GLY, indacaterol–glycopyrronium; NR, not reported; OL, open-label; RR, rate ratio; TIO–OLO, tiotropium–olodaterol; UMEC–VI, umeclidinium–vilanterol.
Health status: margin of efficacy of fixed combinations versus comparators in published studies
| Reference and study | Duration | Treatment | Treatment difference at end point
| |
|---|---|---|---|---|
| SGRQ total score, LSM (95% CI) | % SGRQ responders (OR) | |||
| Bateman et al | 26 weeks | IND–GLY 110/50 μg OD vs Indacaterol 150 μg OD | −1.09 (NR) | 0.7 (NR) |
| −1.18 (NR) | 3.2 (NR) | |||
| −2.13 | 7.3 | |||
| −3.01 | 7.1 (NR) | |||
|
| ||||
| Vogelmeier et al | 26 weeks | IND–GLY 110/50 μg OD vs SFC 50/500 μg BID | −1.24 (−3.33 to 0.85) | 6.4 (1.32) |
|
| ||||
| Wedzicha et al | 64 weeks | IND–GLY 110/50 μg OD vs Glycopyrronium 50 μg OD | −1.9 to −2.8 | NR (1.28) |
| −1.7 to −3.1 | NR (1.29) | |||
|
| ||||
| Buhl et al | 26 weeks | IND–GLY 110/50 μg OD vs tiotropium 18 μg OD + formoterol 12 μg BID | −0.69 (−2.31 to 0.92) | 4.5 (risk ratio 1.11) |
|
| ||||
| Zhong et al | 26 weeks | IND–GLY 110/50 μg OD vs SFC 50/500 μg BID | −0.69 (−2.38 to 1) | NR |
|
| ||||
| Wedzicha et al | 52 weeks | IND–GLY 110/50 μg OD vs SFC 50/500 μg BID | −1.8 | 1.3 |
|
| ||||
| Donohue et al | 24 weeks | UMEC–VI 62.5/25 μg OD vs Umeclidinium 62.5 μg OD | Change from baseline: | |
| −0.82 | 5 (NR) | |||
| −0.32 | 1 (NR) | |||
| −5.51 | 15 (2) | |||
|
| ||||
| Decramer et al | 24 weeks | UMEC–VI 125/25 μg OD | Change from baseline: | |
| 0.75 | 3 (0.9) | |||
| 1.42 | 3 (0.8) | |||
|
| ||||
| Decramer et al | 24 weeks | UMEC–VI 125/25 μg OD | Change from baseline: | |
| −0.17 | 1 (1) | |||
| −1.55 | 6 (1.3) | |||
|
| ||||
| Maleki-Yazdi et al | 24 weeks | UMEC–VI 62.5/25 μg vs tiotropium 18 μg | Change from baseline: | |
| −2.1 | 7 | |||
|
| ||||
| Donohue et al | 12 weeks | UMEC–VI 62.5/25 μg OD vs SFC 50/250 μg BID | ||
| 0.47 (−1.36 to 2.29) | NR | |||
|
| ||||
| Donohue et al | 12 weeks | UMEC–VI 62.5/25 μg OD vs SFC 50/250 μg BID | ||
| −1.55 (−3.63 to 0.53) | NR | |||
|
| ||||
| Buhl et al | 52 weeks | TIO–OLO 2.5/5 μg OD | At 24 weeks: | At 24 weeks: |
| −1.693 | 12.7 | |||
| −1.233 | 8.8 | |||
|
| ||||
| Singh et al | 24 weeks | ACL–FORM 400/6 μg BID | Change from baseline: | |
| −1.59 (−3.52 to 0.35) | NR | |||
| −1.36 (−3.3 to 0.58) | NR | |||
| −0.65 (−3.08 to 1.78) | NR | |||
|
| ||||
| D’Urzo et al | 24 weeks | ACL–FORM 400/6 μg BID | Change from baseline: | |
| −1.87 | 5.8 | |||
| −0.13 | 3.7 | |||
| −4.36 | 19.5 (2.3) | |||
Notes: Treatment once daily unless stated otherwise. SGRQ response = SGRQ total score ≤4 units versus baseline.
Significant treatment difference;
range of LSM differences in scores for weeks 12, 24, 38, 52, and 64 (95% CI not reported);
differences in LSM change from baseline to week 24;
dose not approved for use (ACL–FORM dose not approved in EU);
95% CI not reported;
OR not reported.
Abbreviations: ACL–FORM, aclidinium–formoterol; BID, bis in die (twice daily); CI, confidence interval; IND–GLY, indacaterol–glycopyrronium; LSM, least-squares mean; NR, not reported; OL, open-label; OR, odds ratio; SFC, salmeterol–fluticasone combination; SGRQ, St George’s Respiratory Questionnaire; TIO–OLO, tiotropium–olodaterol; UMEC–VI, umeclidinium–vilanterol.
Search strategy and results for published manuscripts and congress abstracts
| Search number | Search terms | Number of records |
|---|---|---|
| S1 | MeSH.EXACT.EXPLODE (“Bronchodilator Agents”) AND MeSH.EXACT.EXPLODE (“Drug Combinations”) | 821 |
| S2 | “Fixed-dose combination” OR “Fixed dose combination” OR “Fixed-dose long-acting combination” OR “Fixed dose long-acting combination” OR “Fixed-dose combinations” OR “Fixed dose combinations” OR “Fixed-dose long-acting combinations” OR “Fixed dose long-acting combinations” OR “fixed combination” OR “fixed combinations” OR “LABA/LAMA” OR “LAMA/LABA” OR “dual bronchodilator” OR “dual bronchodilators” OR “dual bronchodilation” OR “dual-acting bronchodilator” OR “dual-acting bronchodilators” OR “dual-acting bronchodilation” OR “QVA149” OR “QVA-149” OR “QVA 149” OR “glycopyrronium/indacaterol” OR “indacaterol/glycopyrronium” OR “Anoro” OR “umeclidinium/vilanterol” OR Embase.EXACT (“glycopyrronium bromide plus indacaterol”) | 6,959 |
| S3 | MeSH.EXACT.EXPLODE (“Pulmonary Disease, Chronic Obstructive”) OR “chronic obstructive pulmonary disease” OR “COPD” OR “Chronic Obstructive Lung Disease” OR “Chronic Obstructive Airway Disease” | 90,402 |
| S4 | (S1 OR S2) AND S3 | 444 |
Notes:
Duplicate citations removed from result count
result count includes duplicate citations. ProQuest search, including Biosis, Biosis previews, Embase, and Medline databases. Searches were limited to publications from January 1, 2006 to July 31, 2014 and English-language articles.
Abbreviations: EXACT, EXAcerbations of COPD Tool; EXPLODE, terms indexed as subterms included; LABA, long-acting β2-agonist; LAMA, long-acting muscarinic antagonist; MeSH, Medical Subject Headings.
Congress abstract search strategy and results
| Congress abstracts searched | • Annual Congress of the European Respiratory Society |
| Search terms | “Fixed-dose combination” OR “Fixed dose combination” OR “Fixed-dose long-acting combination” OR “Fixed dose long-acting combination” OR “Fixed-dose combinations” OR “Fixed dose combinations” OR “Fixed-dose long-acting combinations” OR “Fixed dose long-acting combinations” OR “fixed combination” OR “fixed combinations” OR “LABA/LAMA” OR “LAMA/LABA” OR “dual bronchodilator” OR “dual-bronchodilator” OR “dual-bronchodilators” OR “dual-bronchodilation” OR “dual bronchodilators” OR “dual bronchodilation” OR “dual-acting bronchodilator” OR “dual-acting bronchodilators” OR “dual-acting bronchodilation” OR “dual acting bronchodilator” OR “dual acting bronchodilators” OR “dual acting bronchodilation” OR “QVA149” OR “QVA-149” OR “QVA 149” OR “glycopyrronium/indacaterol” OR “indacaterol/glycopyrronium” OR “Anoro” OR “umeclidinium/vilanterol” OR “glycopyrronium bromide plus indacaterol” OR “glycopyrronium plus indacaterol” |
| Number of records | 285 |
Note: Available abstracts from January 1, 2009 to May 20, 2015 were included in the literature search.