Dupilumab for COPD with Blood Eosinophil Evidence of Type 2 Inflammation.

BACKGROUND: Dupilumab, a fully human monoclonal antibody that blocks the shared receptor component for interleukin-4 and interleukin-13, key and central drivers of type 2 inflammation, has shown efficacy and safety in a phase 3 trial involving patients with chronic obstructive pulmonary disease (COPD) and type 2 inflammation and an elevated risk of exacerbation. Whether the findings would be confirmed in a second phase 3 trial was unclear. METHODS: In a phase 3, double-blind, randomized trial, we assigned patients with COPD who had a blood eosinophil count of 300 cells per microliter or higher to receive subcutaneous dupilumab (300 mg) or placebo every 2 weeks. The primary end point was the annualized rate of moderate or severe exacerbations. Key secondary end points, analyzed in a hierarchical manner to adjust for multiplicity, included the changes from baseline in the prebronchodilator forced expiratory volume in 1 second (FEV1) at weeks 12 and 52 and in the St. George's Respiratory Questionnaire (SGRQ; scores range from 0 to 100, with lower scores indicating better quality of life) total score at week 52. RESULTS: A total of 935 patients underwent randomization: 470 were assigned to the dupilumab group and 465 to the placebo group. As prespecified, the primary analysis was performed after a positive interim analysis and included all available data for the 935 participants, 721 of whom were included in the analysis at week 52. The annualized rate of moderate or severe exacerbations was 0.86 (95% confidence interval [CI], 0.70 to 1.06) with dupilumab and 1.30 (95% CI, 1.05 to 1.60) with placebo; the rate ratio as compared with placebo was 0.66 (95% CI, 0.54 to 0.82; P<0.001). The prebronchodilator FEV1 increased from baseline to week 12 with dupilumab (least-squares mean change, 139 ml [95% CI, 105 to 173]) as compared with placebo (least-squares mean change, 57 ml [95% CI, 23 to 91]), with a significant least-squares mean difference at week 12 of 82 ml (P<0.001) and at week 52 of 62 ml (P = 0.02). No significant between-group difference was observed in the change in SGRQ scores from baseline to 52 weeks. The incidence of adverse events was similar in the two groups and consistent with the established profile of dupilumab. CONCLUSIONS: In patients with COPD and type 2 inflammation as indicated by elevated blood eosinophil counts, dupilumab was associated with fewer exacerbations and better lung function than placebo. (Funded by Sanofi and Regeneron Pharmaceuticals; NOTUS ClinicalTrials.gov number, NCT04456673.).

Dupilumab for COPD with Type 2 Inflammation Indicated by Eosinophil Counts.

BACKGROUND: In some patients with chronic obstructive pulmonary disease (COPD), type 2 inflammation may increase exacerbation risk and may be indicated by elevated blood eosinophil counts. Dupilumab, a fully human monoclonal antibody, blocks the shared receptor component for interleukin-4 and interleukin-13, key drivers of type 2 inflammation. METHODS: In a phase 3, double-blind, randomized trial, we assigned patients with COPD who had a blood eosinophil count of at least 300 per microliter and an elevated exacerbation risk despite the use of standard triple therapy to receive dupilumab (300 mg) or placebo subcutaneously once every 2 weeks. The primary end point was the annualized rate of moderate or severe exacerbations of COPD. Key secondary and other end points that were corrected for multiplicity were the change in the prebronchodilator forced expiratory volume in 1 second (FEV1) and in the scores on the St. George's Respiratory Questionnaire (SGRQ; range, 0 to 100, with lower scores indicating a better quality of life) and the Evaluating Respiratory Symptoms in COPD (E-RS-COPD; range, 0 to 40, with lower scores indicating less severe symptoms). RESULTS: A total of 939 patients underwent randomization: 468 to the dupilumab group and 471 to the placebo group. The annualized rate of moderate or severe exacerbations was 0.78 (95% confidence interval [CI], 0.64 to 0.93) with dupilumab and 1.10 (95% CI, 0.93 to 1.30) with placebo (rate ratio, 0.70; 95% CI, 0.58 to 0.86; P<0.001). The prebronchodilator FEV1 increased from baseline to week 12 by a least-squares (LS) mean of 160 ml (95% CI, 126 to 195) with dupilumab and 77 ml (95% CI, 42 to 112) with placebo (LS mean difference, 83 ml; 95% CI, 42 to 125; P<0.001), a difference that was sustained through week 52. At week 52, the SGRQ score had improved by an LS mean of -9.7 (95% CI, -11.3 to -8.1) with dupilumab and -6.4 (95% CI, -8.0 to -4.8) with placebo (LS mean difference, -3.4; 95% CI, -5.5 to -1.3; P = 0.002). The E-RS-COPD score at week 52 had improved by an LS mean of -2.7 (95% CI, -3.2 to -2.2) with dupilumab and -1.6 (95% CI, -2.1 to -1.1) with placebo (LS mean difference, -1.1; 95% CI, -1.8 to -0.4; P = 0.001). The numbers of patients with adverse events that led to discontinuation of dupilumab or placebo, serious adverse events, and adverse events that led to death were balanced in the two groups. CONCLUSIONS: Among patients with COPD who had type 2 inflammation as indicated by elevated blood eosinophil counts, those who received dupilumab had fewer exacerbations, better lung function and quality of life, and less severe respiratory symptoms than those who received placebo. (Funded by Sanofi and Regeneron Pharmaceuticals; BOREAS ClinicalTrials.gov number, NCT03930732.).

Efficacy and Safety of Itepekimab in Patients with Moderate-to-Severe Asthma.

BACKGROUND: Monoclonal antibodies targeting IgE, interleukin-4 and -13, and interleukin-5 are effective in treating severe type 2 asthma, but new targets are needed. Itepekimab is a new monoclonal antibody against the upstream alarmin interleukin-33. The efficacy and safety of itepekimab as monotherapy, as well as in combination with dupilumab, in patients with asthma are unclear. METHODS: In a phase 2 trial, we randomly assigned, in a 1:1:1:1 ratio, adults with moderate-to-severe asthma receiving inhaled glucocorticoids plus long-acting beta-agonists (LABAs) to receive subcutaneous itepekimab (at a dose of 300 mg), itepekimab plus dupilumab (both at 300 mg; combination therapy), dupilumab (300 mg), or placebo every 2 weeks for 12 weeks. After randomization, LABA was discontinued at week 4, and inhaled glucocorticoids were tapered over weeks 6 through 9. The primary end point was an event indicating a loss of asthma control, assessed in the itepekimab group and the combination group, as compared with the placebo group. Secondary and other end points included lung function, asthma control, quality of life, type 2 biomarkers, and safety. RESULTS: A total of 296 patients underwent randomization. By 12 weeks, an event indicating a loss of asthma control occurred in 22% of the patients in the itepekimab group, 27% of those in the combination group, and 19% of those in the dupilumab group, as compared with 41% of those in the placebo group; the corresponding odds ratios as compared with placebo were as follows: in the itepekimab group, 0.42 (95% confidence interval [CI], 0.20 to 0.88; P = 0.02); in the combination group, 0.52 (95% CI, 0.26 to 1.06; P = 0.07); and in the dupilumab group, 0.33 (95% CI, 0.15 to 0.70). As compared with placebo, the forced expiratory volume in 1 second before bronchodilator use increased with the itepekimab and dupilumab monotherapies but not with the combination therapy. Itepekimab treatment improved asthma control and quality of life, as compared with placebo, and led to a greater reduction in the mean blood eosinophil count. The incidence of adverse events was similar in all four trial groups. CONCLUSIONS: Interleukin-33 blockade with itepekimab led to a lower incidence of events indicating a loss of asthma control than placebo and improved lung function in patients with moderate-to-severe asthma. (Funded by Sanofi and Regeneron Pharmaceuticals; ClinicalTrials.gov number, NCT03387852.).

IL-33 Expression Is Lower in Current Smokers at both Transcriptomic and Protein Levels.

Rationale: IL-33 is a proinflammatory cytokine thought to play a role in the pathogenesis of asthma and chronic obstructive pulmonary disease (COPD). A recent clinical trial using an anti-IL-33 antibody showed a reduction in exacerbation and improved lung function in ex-smokers but not current smokers with COPD. Objectives: This study aimed to understand the effects of smoking status on IL-33. Methods: We investigated the association of smoking status with the level of gene expression of IL-33 in the airways in eight independent transcriptomic studies of lung airways. Additionally, we performed Western blot analysis and immunohistochemistry for IL-33 in lung tissue to assess protein levels. Measurements and Main Results: Across the bulk RNA-sequencing datasets, IL-33 gene expression and its signaling pathway were significantly lower in current versus former or never-smokers and increased upon smoking cessation (P < 0.05). Single-cell sequencing showed that IL-33 is predominantly expressed in resting basal epithelial cells and decreases during the differentiation process triggered by smoke exposure. We also found a higher transitioning of this cellular subpopulation into a more differentiated cell type during chronic smoking, potentially driving the reduction of IL-33. Protein analysis demonstrated lower IL-33 levels in lung tissue from current versus former smokers with COPD and a lower proportion of IL-33-positive basal cells in current versus ex-smoking controls. Conclusions: We provide strong evidence that cigarette smoke leads to an overall reduction in IL-33 expression in transcriptomic and protein level, and this may be due to the decrease in resting basal cells. Together, these findings may explain the clinical observation that a recent antibody-based anti-IL-33 treatment is more effective in former than current smokers with COPD.

Deterioration of Limb Muscle Function during Acute Exacerbation of Chronic Obstructive Pulmonary Disease.

Important features of both stable and acute exacerbation of chronic obstructive pulmonary disease (COPD) are skeletal muscle weakness and wasting. Limb muscle dysfunction during an exacerbation has been linked to various adverse outcomes, including prolonged hospitalization, readmission, and mortality. The contributing factors leading to muscle dysfunction are similar to those seen in stable COPD: disuse, nutrition/energy balance, hypercapnia, hypoxemia, electrolyte derangements, inflammation, and drugs (i.e., glucocorticoids). These factors may be the trigger for a downstream cascade of local inflammatory changes, pathway process alterations, and structural degradation. Ultimately, the clinical effects can be wide ranging and include reduced limb muscle strength. Current therapies, such as pulmonary/physical rehabilitation, have limited impact because of low participation rates. Recently, novel drugs have been developed in similar disorders, and learnings from these studies can be used as a foundation to facilitate discovery in patients hospitalized with a COPD exacerbation. Nevertheless, investigators should approach this patient population with knowledge of the limitations of each intervention. In this Concise Clinical Review, we provide an overview of acute muscle dysfunction in patients hospitalized with acute exacerbation of COPD and a strategic approach to drug development in this setting.

Dupilumab reduces exacerbations and improves lung function in patients with chronic obstructive pulmonary disease and emphysema: Phase 3 randomized trial (BOREAS).

BACKGROUND: Dupilumab, a fully human monoclonal antibody that blocks the shared receptor component for interleukin-4 and interleukin-13, reduced exacerbations and improved lung function in patients with chronic obstructive pulmonary disease (COPD) and type 2 inflammation in the phase 3 BOREAS trial. OBJECTIVE: To assess clinical outcomes in patients from BOREAS by emphysema status. METHODS: Patients with COPD and type 2 inflammation (screening blood eosinophils ≥300 cells/µL) on maximal inhaled therapy were randomized to add-on dupilumab 300 mg or placebo every 2 weeks for 52 weeks. We assessed the annualized moderate/severe COPD exacerbation rates over 52 weeks and change from baseline to Week 12 in prebronchodilator forced expiratory volume in 1 second (FEV1) in patients with and without investigator-reported emphysema. RESULTS: Investigator-reported emphysema was present in 306/939 patients (32.6%) at baseline. Dupilumab reduced exacerbation rates vs placebo by 29% (relative risk [RR] 0.71 [95% CI 0.53-0.95]) and 31% (RR 0.69 [95% CI 0.53-0.89]) in patients with and without emphysema, respectively. Prebronchodilator FEV1 least squares mean difference from baseline to Week 12 for dupilumab vs placebo was 0.07 L ([95% CI 0.002-0.14]) and 0.09 L ([95% CI 0.04-0.14]) in patients with and without emphysema, respectively. No treatment by emphysema interaction effect was observed for the annualized rate of exacerbations (P value for interaction = 0.8296) or change in prebronchodilator FEV1 (P value for interaction = 0.6438). CONCLUSION: Dupilumab efficacy was similar in patients with COPD and type 2 inflammation, with or without investigator-reported emphysema.

AERIFY-1/2: two phase 3, randomised, controlled trials of itepekimab in former smokers with moderate-to-severe COPD.

Background: Accumulating data implicate interleukin (IL)-33, a proinflammatory cytokine released locally upon epithelial cell damage, in the pathogenesis of COPD. In a phase 2 study, itepekimab, a human monoclonal antibody against IL-33, reduced exacerbations and improved lung function in a subgroup analysis of former smokers with COPD with an acceptable safety profile. Methods: The study designs of AERIFY-1 and AERIFY-2 are described in this article. Discussion: The primary objective of AERIFY-1/2 (NCT04701983/NCT04751487), two phase 3 randomised, double-blind, placebo-controlled trials, is to assess the efficacy and safety of itepekimab versus placebo in a population of former smokers with moderate-to-severe COPD over up to 52 weeks. An additional secondary population of current smokers are being enrolled in AERIFY-2. These two studies will enrol patients (aged 40-85 years) with COPD and chronic bronchitis who had ≥2 moderate or ≥ 1 severe exacerbations within the previous year despite standard-of-care triple or double background therapy. All participants are required to have ≥10-pack-year smoking history, and ≥6 months since smoking cessation for former smokers. The primary end-point is the annualised rate of moderate or severe acute exacerbation of COPD. Secondary end-points include change from baseline in pre- and post-bronchodilator forced expiratory volume in 1 s, and annualised frequency of severe exacerbations. Symptomatic end-points include Evaluating Respiratory Symptoms in COPD and St. George's Respiratory Questionnaire, safety and anti-drug antibody responses.

Assessment of long-term safety and efficacy of dupilumab in children with asthma (LIBERTY ASTHMA EXCURSION): an open-label extension study.

BACKGROUND: Dupilumab efficacy and safety in children aged 6-11 years with uncontrolled, moderate-to-severe asthma were shown in the VOYAGE study-a 52-week, multinational, multicentre, phase 3 randomised, double-blind, placebo-controlled trial. We aimed to evaluate the long-term safety and efficacy of dupilumab in children with moderate-to-severe asthma who previously participated in the VOYAGE study. METHODS: 365 of 408 children with moderate-to-severe asthma from VOYAGE enrolled in EXCURSION, a 52 week, open-label extension study conducted at 70 centres across 17 countries. 240 children continued with add-on dupilumab (dosed according to bodyweight: 100 mg for those weighing ≤30 kg and 200 mg for those weighing more than 30 kg at EXCURSION baseline) once every 2 weeks administered by subcutaneous injection (dupilumab/dupilumab group) and 125 children on placebo during VOYAGE initiated dupilumab (100 or 200 mg, according to bodyweight), once every 2 weeks administered by subcutaneous injection (placebo/dupilumab group). Following a protocol amendment, for a subset of children weighing 30 kg or less, the dose was changed to 300 mg once every 4 weeks. The primary endpoint for the open-label extension study was the number and proportion of patients with any treatment-emergent adverse event (TEAE) during the 52-week study period in the overall population (defined as children aged 6-11 years old with moderate-to-severe asthma who previously completed VOYAGE). Statistical analyses were descriptive. This study is registered with ClinicalTrials.gov (NCT03560466; EXCURSION). FINDINGS: Children who completed VOYAGE were eligible to enrol in EXCURSION between June 21, 2018 and Aug 18, 2020. During EXCURSION, the safety profile and proportion of patients reporting TEAEs were consistent with those observed during the parent study (VOYAGE). In the overall population, 232 (63·6%) of 365 patients experienced at least one TEAE (dupilumab/dupilumab: 147 [61·3%]; placebo/dupilumab: 85 [68·0%]). The most frequently reported TEAEs were nasopharyngitis, pharyngitis, and upper respiratory tract infections. INTERPRETATION: In EXCURSION, long-term treatment with dupilumab was well tolerated with an acceptable safety profile. FUNDING: Sanofi and Regeneron Pharmaceuticals.

AZD5634, an inhaled ENaC inhibitor, in healthy subjects and patients with cystic fibrosis.

BACKGROUND: Epithelial sodium channel (ENaC) inhibitors may offer clinical benefit in cystic fibrosis (CF); however, data are limited. We report the outcomes of a Phase I (NCT02679729) and a Phase Ib (NCT02950805) study of AZD5634, a novel inhaled ENaC inhibitor. METHODS: A Phase I, first-in-human, single-blind, placebo-controlled, single ascending dose, sequential dose group study assessed the safety, tolerability, and pharmacokinetics of AZD5634 in healthy subjects (n=53) in part A following inhaled doses up to 1700 µg, and, in part B, following administration of single inhaled (1700 µg) and intravenous (65 µg) doses. A Phase Ib, randomized, double-blind, placebo-controlled, single-dose, 2-way cross-over study assessed the effects of a single dose (600 µg) of inhaled AZD5634 on mucociliary clearance (MCC), pharmacokinetics and safety and tolerability in patients with CF (n=11). Nasal potential difference (NPD) was assessed as an in situ target engagement exploratory biomarker. RESULTS: Absolute bioavailability of AZD5634 after inhalation was approximately 3%, indicating minimal distribution into the systemic circulation. Urinary excretion was a minor elimination pathway. Administration of inhaled AZD5634 did not improve MCC in CF patients, but AZD5634 inhibited ENaC in the nasal epithelium, as measured by NPD. AZD5634 was safe and well tolerated in both studies. CONCLUSIONS: AZD5634 showed favorable pharmacokinetics and safety in healthy subjects and patients with CF. However, despite achieving target engagement, proof of mechanism was not achieved after a single dose in patients with CF. Further evaluation into multiple dose studies is warranted to explore its therapeutic potential.

Inclusion and diversity in clinical trials: Actionable steps to drive lasting change.

BACKGROUND: Improving diversity in clinical trials is essential in order to produce generalizable results. Although the importance of representation has become increasingly recognized, identifying strategies to approach this work remains elusive. This article reviews the proceedings of a multi-stakeholder conference about the current state of diversity in clinical trials and outlines actionable steps for improvement. METHODS: Conference attendees included representatives from the United States Food and Drug Administration (FDA), National Institutes of Health (NIH), practicing clinical investigators, pharmaceutical and device companies, community-based organizations, data analytics companies, and patient advocacy groups. At this virtual event, attendees were asked to consider key questions around best practices for engagement of underrepresented populations. RESULTS: Community engagement is an integral part of recruitment and retention of underrepresented groups. Decentralization of sites and use of digital tools can enhance the accessibility of clinical research. Finally, improving representation among investigators and clinical research staff may translate to diverse clinical trial participants. CONCLUSION: Improving diversity in clinical trials is an ethical and scientific imperative, which requires a multifaceted approach.

Safety and efficacy of itepekimab in patients with moderate-to-severe COPD: a genetic association study and randomised, double-blind, phase 2a trial.

BACKGROUND: Genetic data implicate IL-33 in asthma susceptibility. Itepekimab, a monoclonal antibody targeting IL-33, demonstrated clinical activity in asthma, with potential in chronic obstructive pulmonary disease (COPD). In this study we first aimed to test the hypothesis that genetic variants in the IL-33 pathway were also associated with COPD. On the basis of the strong association of IL-33 pathway genes with pulmonary diseases like asthma and COPD, we conducted this phase 2a trial to assess the safety and efficacy of itepekimab in patients with moderate-to-severe COPD on a stable regimen of triple-inhaled or double-inhaled background maintenance therapy. METHODS: In this two-part study, genetic analyses of loss-of-function and gain-of-function variants in the IL-33 pathway, previously associated with asthma risk, were initially characterised for COPD. We then did a double-blind, phase 2a trial comparing itepekimab with placebo in patients with moderate-to-severe COPD despite standard therapy, at 83 study sites in ten countries. Patients aged 40-75 years who were current or former smokers, had been diagnosed with COPD for at least 1 year, and were on a stable regimen of triple-inhaled or double-inhaled background maintenance therapy, were randomly assigned (1:1) to receive itepekimab 300 mg or placebo, administered as two subcutaneous injections every 2 weeks for 24-52 weeks. The primary endpoint of the phase 2a trial was annualised rate of moderate-to-severe acute exacerbations of COPD during the treatment period. The key secondary outcome was change in prebronchodilator FEV1 from baseline to weeks 16-24. Prespecified subgroup analyses were done for each of the endpoints, including by smoking status. Efficacy and safety analyses were done in all participants who received at least one dose of assigned treatment (modified intention-to-treat population). This trial is registered at ClinicalTrials.gov (NCT03546907). FINDINGS: Genetic analyses demonstrated association of loss of function in IL33 with reduced COPD risk, and gain of function in IL33 and IL1RL1 variants with increased risk. Subsequent to this, in the phase 2 trial, 343 patients were randomly assigned to placebo (n=171) or itepekimab (n=172) from July 16, 2018, to Feb 19, 2020. Annualised rates of acute exacerbations of COPD were 1·61 (95% CI 1·32-1·97) in the placebo group and 1·30 (1·05-1·61) in the itepekimab group (relative risk [RR] 0·81 [95% CI 0·61-1·07], p=0·13), and least squares mean prebronchodilator FEV1 change from baseline to weeks 16-24 was 0·0 L (SD 0·02) and 0·06 L (0·02; difference 0·06 L [95% CI 0·01-0·10], p=0·024). When analysis was restricted to former smokers, treatment with itepekimab was associated with nominally significant reductions in acute exacerbations of COPD (RR 0·58 [95% CI 0·39-0·85], p=0·0061) and FEV1 improvement (least squares mean difference 0·09 L [0·02-0·15], p=0·0076) compared with placebo. Current smokers treated with itepekimab showed no treatment benefit versus placebo for exacerbations (RR 1·09 [0·74-1·61], p=0·65) or FEV1 (least squares mean difference 0·02 [-0·05 to 0·09], p=0·54). Treatment-emergent adverse events (TEAEs) occurred in 135 (78%) patients in the itepekimab group and 136 (80%) in the placebo group. The most common TEAEs were nasopharyngitis (28 [16%] in the itepekimab group vs 29 [17%] in the placebo group), bronchitis (18 [10%] vs 14 [8%]), headache (14 [8%] vs 23 [13%]), and upper respiratory tract infection (13 [8%] vs 15 [9%]). INTERPRETATION: The primary endpoint in the overall population was not met, subgroup analysis showed that itepekimab reduced exacerbation rate and improved lung function in former smokers with COPD. Two phase 3 clinical studies are ongoing to confirm the efficacy and safety profile of itepekimab in former smokers with COPD. FUNDING: Sanofi and Regeneron Pharmaceuticals.

Evolution of PI3Kγ and δ Inhibitors for Inflammatory and Autoimmune Diseases.

Phosphoinositol 3-kinases (PI3Ks) γ and δ are key enzymes in hematopoietic cells and have been seen as high-value targets for the treatment of diseases with inflammatory and immunomodulatory components since their discovery and the identification of their roles. In this Perspective we review progress in the application of inhibitors of PI3Kγ and δ to inflammatory and immunological conditions over the past 6 years. We consider progress in the understanding of the roles of PI3Kγ and PI3Kδ in immunology and inflammation, the experience from clinical trials where inhibitors have been tested, and what has been learned about the safety of their use. The extensive medicinal chemistry efforts to discover both isoform selective and dual PI3Kγδ inhibitors are analyzed and detailed. Developments in understanding the structural chemistry of the PI3K enzymes and the factors that govern isoform selectivity are discussed. The effects observed with the known inhibitor compounds in animal models are described.

Provider and interpreter preferences among Somali women in a primary care setting.

OBJECTIVES: Somali people are among the largest refugee populations to resettle in North America and Europe over the past 2 decades, and health disparities are well documented, including barriers to effective navigation of primary health care systems. Patient-provider gender discordance has been described as a barrier to health-seeking behaviors and effective communication by Somali women in past qualitative work. The objective of this study was to elucidate provider and interpreter preferences during clinical encounters according to gender and race among Somali women in the United States. METHODS: Fifty Somali women empanelled to a large primary care practice completed pictorial surveys to elucidate preferences of Somali women for providers of different genders and race for different components of the clinical examination using a Likert-type scale. RESULTS: We found that Somali women generally preferred a female provider for conducting the physical examination, particularly for the pelvic, breast, and abdominal examinations. Likewise, Somali women strongly preferred female interpreters to be present during the physical examination. There was no stated preference for patient-provider racial concordance. CONCLUSIONS: These findings have implications for structural health care changes aimed at delivering culturally sensitive and effective primary care to Somali patients.

Risk factors and outcome of pulmonary complications after autologous hematopoietic stem cell transplant.

BACKGROUND: Most reports addressing pulmonary complications (PCs) in hematopoietic stem cell transplant (HSCT) recipients have focused on allogeneics. This study describes the PCs, their risk factors, and the impact on mortality in autologous recipients. METHODS: We reviewed the medical records of 1,243 adult autologous HSCT recipients. We collected pretransplant and posttransplant data and data on PC after transplant and long-term mortality. RESULTS: Four hundred eighty-seven PC developed in 343 patients (27.6%): 173 infectious (13.9%), 127 noninfectious (10.2%), and 43 both infectious and noninfectious (3.5%). Bacterial, fungal, and viral pneumonias were the most common infectious complications. The main noninfectious complications were acute pulmonary edema (APE) (59 [4.7%]), diffuse alveolar hemorrhage (DAH) (26 [2.1%]), peri-engraftment respiratory distress syndrome (PERDS) (31 [2.5%]), and idiopathic pneumonia syndrome (IPS) (12 [1.0%]). Independent factors associated with PC included diffusing capacity of lung for carbon monoxide and indications for transplant. Factors associated with mortality included sex, history of pulmonary disease, disease status at the time of transplant, FVC, Karnofsky score, and underlying diagnosis. A Cox proportional hazards regression model with separate time-dependent predictors for the first 1 month, 1 to 2 months, 2 to 6 months, and 6 or more months showed an association with mortality at hazard ratios (HRs) of 32.39, 10.13, 4.29, and 0.98, respectively, compared with persons without PC. CONCLUSIONS: More than 25% of autologous HSCT recipients develop PCs within 1 year of transplant. Most of the complications are infections. The most common noninfectious complications are APE, DAH, PERDS, and IPS. PCs increase the risk of death, with HR as high as 32.