The DisEntangling Chronic Obstructive pulmonary Disease Exacerbations clinical trials NETwork (DECODE-NET): rationale and vision

Effectiveness of immunoglobulin replacement therapy in preventing infections in patients with chronic obstructive pulmonary disease: a systematic review

PURPOSE

Immunoglobulin replacement therapy is a standard treatment for patients with antibody production deficiencies, which is of interest in patients with chronic obstructive pulmonary disease (COPD). This systematic review, registered with PROSPERO (CRD42021281118), assessed the current literature regarding immunoglobulin replacement therapy on COPD clinical outcomes in patients with low immunoglobulin G (IgG) serum concentrations.

METHODS

Literature searches conducted from inception to August 23, 2021, in databases including MEDLINE, EMBASE, and CINAHL. Population (sex, age, comorbidities), baseline clinical characteristics (pulmonary function testing results, IgG levels), and outcome (hospitalizations, emergency department visits) were extracted after title/abstract and full text screening. The Cochrane risk of bias assessment form was used for risk of bias assessment of randomized controlled trials and the National Heart, Lung, and Blood Institute (NHLBI) assessment was used for pre and post studies.

RESULTS

A total of 1381 studies were identified in the preliminary search, and 874 records were screened after duplicates were removed. Screening 77 full texts yielded four studies that were included in the review.

CONCLUSION

It is unclear whether immune globulin replacement therapy reduces acute exacerbation frequency and severity in COPD. Current evidence suggests that it is worth considering, but better developed protocols for administration of immune globulin supplementation is required for future randomized controlled trials.

Complexity in clinical diagnoses of acute exacerbation of chronic obstructive pulmonary disease

BACKGROUND

Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is a clinical syndrome with various causes. It is not uncommon that COPD patients presenting with dyspnea have multiple causes for their symptoms including AECOPD, pneumonia, or congestive heart failure occurring concurrently.

METHODS

To identify clinical, radiographic, and laboratory characteristics that might help distinguish AECOPD from another dominant disease in patients with a history of COPD, we conducted a retrospective cohort study of hospitalized patients with admitting diagnosis of AECOPD who were screened for a prospective randomized controlled trial from Sep 2016 to Mar 2018. Clinical characteristics, course in hospital, and final diagnosis at discharge were reviewed and adjudicated by two authors. The final diagnosis of each patient was determined based on the synthesis of all presenting signs and symptoms, imaging, and laboratory results. We adhered to AECOPD diagnosis definitions based on the GOLD guidelines. Univariate and multivariate analyses were performed to identify any associated features of AECOPD with and without other acute processes contributing to dyspnea.

RESULTS

Three hundred fifteen hospitalized patients with admitting diagnosis of AECOPD were included. Mean age was 72.5 (SD 10.6) years. Two thirds (65.4%) had spirometry defined COPD. The most common presenting symptom was dyspnea (96.5%), followed by cough (67.9%), and increased sputum (57.5%). One hundred and eighty (57.1%) had a final diagnosis of AECOPD alone whereas 87 (27.6%) had AECOPD with other conditions and 48 (15.2%) did not have AECOPD after adjudication. Increased sputum purulence (OR 3.35, 95%CI 1.68-6.69) and elevated venous pCO2 (OR 1.04, 95%CI 1.01 - 1.07) were associated with a diagnosis of AECOPD but these were not associated with AECOPD alone without concomitant conditions. Radiographic evidence of pleural effusion (OR 0.26, 95%CI 0.12 - 0.58) was negatively associated with AECOPD with or without other conditions while radiographic evidence of pulmonary edema (OR 0.31; 95%CI 0.11 - 0.91) and lobar pneumonia (OR 0.13, 95%CI 0.07 - 0.25) suggested against the diagnosis of AECOPD alone.

CONCLUSION

The study highlighted the complexity and difficulty of AECOPD diagnosis. A more specific clinical tool to diagnose AECOPD is needed.

Mucolytics for acute exacerbations of chronic obstructive pulmonary disease: a meta-analysis

This meta-analysis explored the safety and effectiveness of mucolytics as an add-on treatment for chronic obstructive pulmonary disease (COPD) exacerbations. Based on a pre-registered protocol and following Cochrane methods, we systematically searched for relevant randomised or quasi-randomised controlled trials (RCTs). We used the Risk of Bias v2 tool for appraising the studies and performed random-effect meta-analyses when appropriate. We assessed certainty of evidence using GRADE. This meta-analysis included 24 RCTs involving 2192 patients with COPD exacerbations, entailing at least some concerns of methodological bias. We demonstrated with moderate certainty that mucolytics increase the rate of treatment success (relative risk 1.37, 95% CI 1.08-1.73, n=383), while they also exert benefits on overall symptom scores (standardised mean difference 0.86, 95% CI 0.63-1.09, n=316), presence of cough at follow-up (relative risk 1.93, 95% CI 1.15-3.23) and ease of expectoration (relative risk 2.94, 95% CI 1.68-5.12). Furthermore, low or very low certainty evidence suggests mucolytics may also reduce future risk of exacerbations and improve health-related quality of life, but do not impact on breathlessness, length of hospital stay, indication for higher level of care or serious adverse events. Overall, mucolytics could be considered for COPD exacerbation management. These findings should be validated in further, rigorous RCTs.

ERS statement: a core outcome set for clinical trials evaluating the management of COPD exacerbations

Clinical trials evaluating the management of acute exacerbations of COPD assess heterogeneous outcomes, often omitting those that are clinically relevant or more important to patients. We have developed a core outcome set, a consensus-based minimum set of important outcomes that we recommend are evaluated in all future clinical trials on exacerbations management, to improve their quality and comparability. COPD exacerbations outcomes were identified through methodological systematic reviews and qualitative interviews with 86 patients from 11 countries globally. The most critical outcomes were prioritised for inclusion in the core outcome set through a two-round Delphi survey completed by 1063 participants (256 patients, 488 health professionals and 319 clinical academics) from 88 countries in five continents. Two global, multi-stakeholder, virtual consensus meetings were conducted to 1) finalise the core outcome set and 2) prioritise a single measurement instrument to be used for evaluating each of the prioritised outcomes. Consensus was informed by rigorous methodological systematic reviews. The views of patients with COPD were accounted for at all stages of the project. Survival, treatment success, breathlessness, quality of life, activities of daily living, the need for a higher level of care, arterial blood gases, disease progression, future exacerbations and hospital admissions, treatment safety and adherence were all included in the core outcome set. Focused methodological research was recommended to further validate and optimise some of the selected measurement instruments. The panel did not consider the prioritised set of outcomes and associated measurement instruments to be burdensome for patients and health professionals to use.

A Randomized Double-Blind Placebo-Control Feasibility Trial of Immunoglobulin Treatment for Prevention of Recurrent Acute Exacerbations of COPD

Background

Observational studies suggest that immunoglobulin treatment may reduce the frequency of acute exacerbations of COPD (AECOPD).

Objective

To inform the design of a future randomised control trial (RCT) of intravenous immunoglobulin (IVIG) treatment efficacy for AECOPD prevention.

Methods

A pilot RCT was conducted. We recruited patients with COPD hospitalized for AECOPD, or from ambulatory clinics with one severe, or two moderate AECOPD in the previous year regardless of their serum IgG level. Patients were allocated in a 1:1 ratio with balanced randomisation to monthly IVIG or normal saline for 1 year. The primary outcome was feasibility defined as pre-specified accrual, adherence, and follow-up rates. Secondary outcomes included safety, tolerance, AECOPD rates, time to first AECOPD, quality of life, and healthcare costs.

Results

Seventy patients were randomized (37 female; mean age 67.7; mean FEV1 35.1%). Recruitment averaged 4.5±0.9 patients per month (range 0–8), 34 (49%) adhered to at least 80% of planned treatments, and four (5.7%) were lost to follow-up. There were 35 serious adverse events including seven deaths and one thromboembolism. None was related to IVIG. There were 56 and 48 moderate and severe AECOPD in the IVIG vs control groups. In patients with at least 80% treatment adherence, median time to first moderate or severe AECOPD was 275 vs 114 days, favoring the IVIG group (HR 0.76, 95% CI 0.3–1.92).

Conclusion

The study met feasibility criteria for recruitment and retention, but adherence was low. A trend toward more robust treatment efficacy in adherent patients supports further study, but future trials must address treatment adherence.

Trial registration number

NCT0290038, registered 24 February 2016, https://clinicaltrials.gov/ct2/show/NCT02690038 and NCT03018652, registered January 12, 2017, https://clinicaltrials.gov/ct2/show/NCT03018652.

Assessing Treatment Success or Failure as an Outcome in Randomised Clinical Trials of COPD Exacerbations. A Meta-Epidemiological Study

A recently published ERS core outcome set recommends that all trials of COPD exacerbation management should assess the treatment success (or “cure” of the exacerbation), defined as a dichotomous measure of the overall outcome of an exacerbation. This methodological systematic review describes and compares the instruments that were used to assess treatment success or failure in 54 such RCTs, published between 2006–2020. Twenty-three RCTs used composite measures consisting of several undesirable outcomes of an exacerbation, together defining an overall unfavourable outcome, to define treatment failure. Thirty-four RCTs used descriptive instruments that used qualitative or semi-quantitative descriptions to define cure, marked improvement, improvement of the exacerbation, or treatment failure. Treatment success and failure rates among patients receiving guidelines-directed treatments at different settings and timepoints are described and could be used to inform power calculations in future trials. Descriptive instruments appeared more sensitive to treatment effects compared to composite instruments. Further methodological studies are needed to optimise the evaluation of treatment success/failure. In the meantime, based on the findings of this systematic review, the ERS core outcome set recommends that cure should be defined as sufficient improvement of the signs and symptoms of the exacerbation such that no additional systemic treatments are required.

MULTI-PHACET: multidimensional clinical phenotyping of hospitalised acute COPD exacerbations

Background

The generic term “exacerbation” does not reflect the heterogeneity of acute exacerbations of COPD (AECOPD). We utilised a novel algorithmic strategy to profile exacerbation phenotypes based on underlying aetiologies.

Methods

Patients hospitalised for AECOPD (n=146) were investigated for aetiological contributors summarised in a mnemonic acronym ABCDEFGX (A: airway virus; B: bacterial; C: co-infection; D: depression/anxiety; E: eosinophils; F: failure (cardiac); G: general environment; X: unknown). Results from clinical investigations were combined to construct AECOPD phenotypes. Relationships to clinical outcomes were examined for both composite phenotypes and their specific aetiological components. Aetiologies identified at exacerbation were reassessed at outpatient follow-up.

Results

Hospitalised AECOPDs were remarkably diverse, with 26 distinct phenotypes identified. Multiple aetiologies were common (70%) and unidentifiable aetiology rare (4.1%). If viruses were detected (29.5%), patients had longer hospitalisation (7.7±5.6 versus 6.0±3.9 days, p=0.03) despite fewer “frequent exacerbators” (9.3% versus 37%, p=0.001) and lower mortality at 1 year (p=0.03). If bacterial infection was found (40.4%), patients were commonly “frequent exacerbators” (44% versus 18.4%, p=0.001). Eosinophilic exacerbations (28%) were associated with lower pH (7.32±0.06 versus 7.36±0.09, p=0.04), higher venous carbon dioxide tension (P_vCO2) (53.7±10.5 versus 48.8±12.8, p=0.04), greater noninvasive ventilation (NIV) usage (34.1% versus 18.1%) but shorter hospitalisation (4 (3–5) versus 6 (4–9) days, p<0.001) and lower infection rates (41.4% versus 80.9%, p<0.0001). Cardiac dysfunction and severe anxiety/depression were common in both infective and non-infective exacerbations. Characteristics identified at exacerbation often persisted after recovery.

Conclusions

Hospitalised AECOPDs have numerous causes, often in combination, that converge in complex, multi-faceted phenotypes. Clinically important differences in outcomes suggest that a phenotyping strategy based on aetiologies can enhance AECOPD management.

Hospitalised #AECOPD present as complex multidimensional clinical phenotypes, often comprising multiple distinct aetiologies. Profiling AECOPDs according to their multifactorial aetiological components has important prognostic and therapeutic implications.https://bit.ly/3nIHEnO

Alpha-1 antitrypsin deficiency and recombinant protein sources with focus on plant sources: Updates, challenges and perspectives

Alpha-1 antitrypsin deficiency (A1ATD) is an autosomal recessive disease characterized by low plasma levels of A1AT, a serine protease inhibitor representing the most abundant circulating antiprotease normally present at plasma levels of 1-2 g/L. The dominant clinical manifestations include predispositions to early onset emphysema due to protease/antiprotease imbalance in distal lung parenchyma and liver disease largely due to unsecreted polymerized accumulations of misfolded mutant A1AT within the endoplasmic reticulum of hepatocytes. Since 1987, the only FDA licensed specific therapy for the emphysema component has been infusions of A1AT purified from pooled human plasma at the 2020 cost of up to US $200,000/year with the risk of intermittent shortages. In the past three decades various, potentially less expensive, recombinant forms of human A1AT have reached early stages of development, one of which is just reaching the stage of human clinical trials. The focus of this review is to update strategies for the treatment of the pulmonary component of A1ATD with some focus on perspectives for therapeutic production and regulatory approval of a recombinant product from plants. We review other competitive technologies for treating the lung disease manifestations of A1ATD, highlight strategies for the generation of data potentially helpful for securing FDA Investigational New Drug (IND) approval and present challenges in the selection of clinical trial strategies required for FDA licensing of a New Drug Approval (NDA) for this disease.

Current developments and future directions in COPD

The European Respiratory Society journals publish respiratory research and policy documents of the highest quality, offering a platform for the exchange and promotion of scientific knowledge. In this article, focusing on COPD, the third leading cause of death globally, we summarise novel research highlights focusing on the disease's underlying mechanisms, epidemiology and management, with the aim to inform and inspire respiratory clinicians and researchers.

Current developments and future directions in COPD: a critical summary of some of the most recent ground-breaking research studies and policy documents from @ERSpublicationshttps://bit.ly/3oW0xDM

Core outcome set for the management of acute exacerbations of chronic obstructive pulmonary disease: the COS-AECOPD ERS Task Force study protocol

Randomised controlled trials (RCTs) on the management of COPD exacerbations evaluate heterogeneous outcomes, often omitting those that are clinically important and patient relevant. This limits their usability and comparability. A core outcome set (COS) is a consensus-based minimum set of clinically important outcomes that should be evaluated in all RCTs in specific areas of health care. We present the study protocol of the COS-AECOPD ERS Task Force, aiming to develop a COS for COPD exacerbation management, that could remedy these limitations. For the development of this COS we follow standard methodology recommended by the COMET initiative. A comprehensive list of outcomes is assembled through a methodological systematic review of the outcomes reported in relevant RCTs. Qualitative research with patients with COPD will also be conducted, aiming to identify additional outcomes that may be important to patients, but are not currently addressed in clinical research studies. Prioritisation of the core outcomes will be facilitated through an extensive, multi-stakeholder Delphi survey with a global reach. Selection will be finalised in an international, multi-stakeholder meeting. For every core outcome, we will recommend a specific measurement instrument and standardised time points for evaluation. Selection of instruments will be based on evidence-informed consensus. Our work will improve the quality, usability and comparability of future RCTs on the management of COPD exacerbations and, ultimately, the care of patients with COPD. Multi-stakeholder engagement and societal support by the European Respiratory Society will raise awareness and promote implementation of the COS.