Hyperammonemic encephalopathy after tyrosine kinase inhibitors: A literature review and a case example.

OBJECTIVE: To review the evidence of uncommon but fatal adverse event of hyperammonemic encephalopathy by tyrosine kinase inhibitors (TKI) and the possible mechanisms underlying this condition and to describe the case of a patient that developed drug-induced hyperammonemic encephalopathy related to TKI. DATA SOURCES: Literature search of different databases was performed for studies published from 1 January 1992 to 7 May 2023. The search terms utilized were hyperammonemic encephalopathy, TKI, apatinib, pazopanib, sunitinib, imatinib, sorafenib, regorafenib, trametinib, urea cycle regulation, sorafenib, carbamoyl-phosphate synthetase 1, ornithine transcarbamylase, argininosuccinate synthetase, argininosuccinate lyase, arginase 1, Mitogen activated protein kinases (MAPK) pathway and mTOR pathway, were used individually search or combined. DATA SUMMARY: Thirty-seven articles were included. The articles primarily focused in hyperammonemic encephalopathy case reports, management of hyperammonemic encephalopathy, urea cycle regulation, autophagy, mTOR and MAPK pathways, and TKI. CONCLUSION: Eighteen cases of hyperammonemic encephalopathy were reported in the literature from various multitargeted TKI. The mechanism of this event is not well-understood but some authors have hypothesized vascular causes since some of TKI are antiangiogenic, however our literature review shows a possible relationship between the urea cycle and the molecular inhibition exerted by TKI. More preclinical evidence is required to unveil the biochemical mechanisms responsible involved in this process and clinical studies are necessary to shed light on the prevalence, risk factors, management and prevention of this adverse event. It is important to monitor neurological symptoms and to measure ammonia levels when manifestations are detected.

Impact of SARS-CoV-2 vaccines and recent chemotherapy on COVID-19 morbidity and mortality in patients with soft tissue sarcoma: an analysis from the OnCovid registry.

Background: To date, limited evidence exists on the impact of COVID-19 in patients with soft tissue sarcoma (STS), nor about the impact of SARS-CoV-2 vaccines and recent chemotherapy on COVID-19 morbidity and mortality in this specific population. Methods: We described COVID-19 morbidity and mortality among patients with STS across 'Omicron' (15 December 2021-31 January 2022), 'Pre-vaccination' (27 February 2020-30 November 2020), and 'Alpha-Delta' phase (01 December 2020-14 December 2021) using OnCovid registry participants (NCT04393974). Case fatality rate at 28 days (CFR28) and COVID-19 severity were also described according to the SARS-CoV-2 vaccination status, while the impact of the receipt of cytotoxic chemotherapy within 4 weeks prior to COVID-19 on clinical outcomes was assessed with Inverse Probability of Treatment Weighting (IPTW) models adjusted for possible confounders. Results: Out of 3820 patients, 97 patients with STS were included. The median age at COVID-19 diagnosis was 56 years (range: 18-92), with 65 patients (67%) aged < 65 years and most patients had a low comorbidity burden (65, 67.0%). The most frequent primary tumor sites were the abdomen (56.7%) and the gynecological tract (12.4%). In total, 36 (37.1%) patients were on cytotoxic chemotherapy within 4 weeks prior to COVID-19. The overall CFR28 was 25.8%, with 38% oxygen therapy requirement, 34% rate of complications, and 32.3% of hospitalizations due to COVID-19. CFR28 (29.5%, 21.4%, and 12.5%) and all indicators of COVID-19 severity demonstrated a trend toward a numerical improvement across the pandemic phases. Similarly, vaccinated patients demonstrated numerically improved CFR28 (16.7% versus 27.7%) and COVID-19 morbidity compared with unvaccinated patients. Patients who were on chemotherapy experienced comparable CFR28 (19.4% versus 26.0%, p = 0.4803), hospitalizations (50.0% versus 44.4%, p = 0.6883), complication rates (30.6% versus 34.0%, p = 0.7381), and oxygen therapy requirement (28.1% versus 40.0%, p = 0.2755) compared to those who were not on anticancer therapy at COVID-19, findings further confirmed by the IPTW-fitted multivariable analysis. Conclusion: In this study, we demonstrate an improvement in COVID-19 outcomes in patients with STS over time. Recent exposure to chemotherapy does not impact COVID-19 morbidity and mortality and SARS-CoV-2 vaccination confers protection against adverse outcomes from COVID-19 in this patient population.

An analysis from the OnCovid registry on the impact of chemotherapy and SARS-CoV-2 vaccines on clinical outcomes of patients with soft tissue sarcoma and COVID-19 Soft tissue sarcomas (STS) are a group of rare and aggressive tumours, usually treated with high dose cytotoxic chemotherapy. To date no clear evidence exists on the impact of COVID-19 in patients with STS, nor on the potential impact of recent chemotherapy and prior SARS-CoV-2 vaccination in this specific patient population. This is the 1st study to show COVID-19 outcomes in patients with STS, highlighting a substantial vaccine efficacy with no negative impact of recent chemotherapy on COVID-19 outcomes.

Previous immune checkpoint inhibitor therapy is associated with decreased COVID-19-related hospitalizations and complications in patients with cancer: Results of a propensity-matched analysis of the OnCovid registry.

OBJECTIVES: To date, studies have not provided definitive answers regarding whether previous immune checkpoint inhibitor (ICI) treatment alters outcomes for cancer patients with COVID-19. METHODS: The OnCovid registry (NCT04393974) was searched from February 27, 2020, to January 31, 2022, for patients who received systemic anti-cancer therapy in the 4 weeks before laboratory-confirmed COVID-19 diagnosis. Propensity-score matching using country, vaccination status, primary tumor type, sex, age, comorbidity burden, tumor stage, and remission status investigated differences in predefined clinical outcomes comparing those who had or had not received ICIs. RESULTS: Of 3523 patients screened, 137 ICI-only and 1378 non-ICI met inclusion criteria. Before matching, ICI patients were older, male, enrolled at centers in Italy, and had histories of smoking, thoracic cancers, advanced cancer stages, and active malignancies (P ≤0.02). After matching, there were 120 ICI and 322 non-ICI patients. ICI patients had no differences (odds ratio: 95% CI) in presenting COVID-19 symptoms (0.69: 0.37-1.28), receipt of COVID-specific therapy (0.88: 0.54-1.41), 14-day (0.95: 0.56-1.61), or 28-day (0.79: 0.48-1.29) mortalities. However, ICI patients required less COVID-19-related hospitalization (0.37: 0.21-0.67) and oxygen therapy (0.51: 0.31-0.83) and developed fewer complications (0.57: 0.36-0.92). CONCLUSION: In this propensity-score matched analysis, previous ICI therapy did not worsen and potentially improved COVID-19 outcomes in patients with cancer.

Impact of viral detection in patients with community-acquired pneumonia: An observational cohort study / Impacto de la detección viral en pacientes con neumonía comunitaria: estudio de cohortes observacional

Purpose The presence of a respiratory virus in patients with community-acquired pneumonia (CAP) may have an impact on the bacterial etiology and clinical presentation. In this study we aimed to assess the role of viral infection in the bacterial etiology and outcomes of patients with CAP. Methods We performed a retrospective study of all adults hospitalized with CAP between November 2017 and October 2018. Patients were classified according to the presence of viral infection. An unvaried and a multivaried analysis were performed to identify variables associated with viral infection and clinical outcomes. Results Overall 590 patients were included. A microorganism was documented in 375 cases (63.5%). A viral infection was demonstrated in 118 (20%). The main pathogens were Streptococcus pneumoniae (35.8%), Staphylococcus aureus (2.9%) and influenza virus (10.8%). A trend to a higher rate of S. aureus (p = 0.06) in patients with viral infection was observed. Patients with viral infection had more often bilateral consolidation patterns (17.8% vs 10.8%, p = 0.04), respiratory failure (59.3% vs 42.8%, p = 0.001), ICU admission (17.8% vs 7%, p = 0.001) and invasive mechanical ventilation (9.3% vs 2.8%, p = 0.003). Risk factors for respiratory failure were chronic lung disease, age >65 years, positive blood cultures and viral infection. Influenza, virus but no other respiratory viruses, was associated with respiratory failure (OR, 3.72; 95% CI, 2.06–6.73). Conclusions Our study reinforces the idea that co-viral infection has an impact in the clinical presentation of CAP causing a more severe clinical picture. This impact seems to be mainly due to influenza virus infection (AU)

Objetivos La presencia de virus respiratorios en pacientes con neumonía adquirida en la comunidad (NAC) puede tener un impacto en la etiología bacteriana y en la presentación clínica. El objetivo de este estudio fue evaluar el papel de la infección viral en la etiología bacteriana y la evolución de los pacientes con NAC. Métodos Realizamos un estudio retrospectivo de todos los adultos hospitalizados con diagnóstico de NAC entre noviembre de 2017 y octubre de 2018. Los pacientes fueron clasificados según la presencia de infección viral. Se realizó un análisis univariado y multivariado para identificar variables asociadas con la infección viral y la evolución clínica. Resultados En total se incluyeron 590 pacientes. Se documentó el microorganismo en 375 casos (63,5%). Se demostró una infección viral en 118 (20%). Los principales patógenos fueron S. pneumoniae (35,8%), S. aureus (2,9%) y virus de la influenza (10,8%). Se observó una tendencia a una mayor tasa de S. aureus (p = 0,06) en pacientes con infección viral. Los pacientes con infección viral tenían con mayor frecuencia patrones de consolidación bilateral (17,8% vs 10,8%; p = 0,04), insuficiencia respiratoria (59,3% vs 42,8%; p = 0,001), ingreso en UCI (17,8% vs 7%; p = 0,001) y necesidad de ventilación mecánica invasiva (9,3% vs 2,8%; p = 0,003). Los factores de riesgo para insuficiencia respiratoria fueron enfermedad pulmonar crónica, edad >65 años, hemocultivos positivos e infección viral. El virus de la influenza, pero ningún otro virus respiratorio, se asoció con insuficiencia respiratoria (OR: 3,72; IC 95%: 2,06-6,73). Conclusiones Nuestro estudio refuerza la idea de que la infección viral tiene un impacto en la presentación clínica de la NAC provocando un cuadro clínico más grave. Este impacto parece deberse principalmente a la infección por el virus de la influenza (AU)

Impact of viral detection in patients with community-acquired pneumonia: An observational cohort study.

PURPOSE: The presence of a respiratory virus in patients with community-acquired pneumonia (CAP) may have an impact on the bacterial etiology and clinical presentation. In this study we aimed to assess the role of viral infection in the bacterial etiology and outcomes of patients with CAP. METHODS: We performed a retrospective study of all adults hospitalized with CAP between November 2017 and October 2018. Patients were classified according to the presence of viral infection. An unvaried and a multivaried analysis were performed to identify variables associated with viral infection and clinical outcomes. RESULTS: Overall 590 patients were included. A microorganism was documented in 375 cases (63.5%). A viral infection was demonstrated in 118 (20%). The main pathogens were Streptococcus pneumoniae (35.8%), Staphylococcus aureus (2.9%) and influenza virus (10.8%). A trend to a higher rate of S. aureus (p=0.06) in patients with viral infection was observed. Patients with viral infection had more often bilateral consolidation patterns (17.8% vs 10.8%, p=0.04), respiratory failure (59.3% vs 42.8%, p=0.001), ICU admission (17.8% vs 7%, p=0.001) and invasive mechanical ventilation (9.3% vs 2.8%, p=0.003). Risk factors for respiratory failure were chronic lung disease, age >65 years, positive blood cultures and viral infection. Influenza, virus but no other respiratory viruses, was associated with respiratory failure (OR, 3.72; 95% CI, 2.06-6.73). CONCLUSIONS: Our study reinforces the idea that co-viral infection has an impact in the clinical presentation of CAP causing a more severe clinical picture. This impact seems to be mainly due to influenza virus infection.

Vaccination against SARS-CoV-2 protects from morbidity, mortality and sequelae from COVID19 in patients with cancer.

BACKGROUND: Although SARS-CoV-2 vaccines immunogenicity in patients with cancer has been investigated, whether they can significantly improve the severity of COVID-19 in this specific population is undefined. METHODS: Capitalizing on OnCovid (NCT04393974) registry data we reported COVID-19 mortality and proxies of COVID-19 morbidity, including post-COVID-19 outcomes, according to the vaccination status of the included patients. RESULTS: 2090 eligible patients diagnosed with COVID-19 between 02/2020 and 11/2021 were included, of whom 1930 (92.3%) unvaccinated, 91 (4.4%) fully vaccinated and 69 (3.3%) partially vaccinated. With the exception of a higher prevalence of patients from the UK (p = 0.0003) and receiving systemic anticancer therapy at COVID-19 diagnosis (p = 0.0082) among fully vaccinated patients, no demographics/oncological features were associated with vaccination status. The 14-days case fatality rate (CFR) (5.5% vs 20.7%, p = 0.0004) and the 28-days CFR (13.2% vs 27.4%, p = 0.0028) demonstrated a significant improvement for fully vaccinated patients in comparison with unvaccinated patients. The receipt of prior full vaccination was also associated with reduced symptomatic COVID-19 (79.1% vs 88.5%, p = 0.0070), need of COVID-19 oriented therapy (34.9% vs 63.2%, p < 0.0001), complications from COVID-19 (28.6% vs 39.4%, p = 0.0379), hospitalizations due to COVID-19 (42.2% vs 52.5%, p = 0.0007) and oxygen therapy requirement (35.7% vs 52%, p = 0.0036). Following Inverse Probability Treatment Weighting (IPTW) procedure no statistically significant difference according to the vaccination status was confirmed; however, all COVID-19 related outcomes were concordantly in favour of full vaccination. Among the 1228 (58.8%) patients who underwent a formal reassessment at participating centres after COVID-19 resolution, fully vaccinated patients experienced less sequelae than unvaccinated patients (6.7% vs 17.2%, p = 0.0320). CONCLUSIONS: This analysis provides initial evidence in support of the beneficial effect of SARS-CoV-2 vaccines against morbidity and mortality from COVID-19 in patients with cancer.

Early outcomes in adults hospitalized with severe SARS-CoV-2 infection receiving tocilizumab.

Background: Modulation of the immune system to prevent lung injury is being widely used against the new coronavirus disease (COVID-19). The primary endpoint was mortality at 7 days after tocilizumab administration. Secondary endpoints were admission to the intensive care unit, development of ARDS and respiratory insufficiency among others. Methods: We report the preliminary results from the Vall d'Hebron cohort study at Vall d'Hebron University Hospital, in Barcelona (Spain), including all consecutive patients who had a confirmed SARS-CoV-2 infection and who were treated with tocilizumab until March 25th. Results: 82 patients with COVID-19 received at least one dose of tocilizumab. The mean (± SD) age was 59.1 (19.8) years, 63% were male, 22% were of non-Spanish ancestry, and the median (IQR) age-adjusted Charlson index at baseline was 3 (1-4) points. Respiratory failure and ARDS developed in 62 (75.6%) and 45 (54.9%) patients, respectively. Median time from symptom onset to ARDS development was 8 (5-11) days. Mortality at 7 days was 26.8%. Hazard ratio for mortality was 3.3; 95% CI, 1.3-8.5 (age-adjusted hazard ratio for mortality 2.1; 95% CI, 0.8-5.8) if tocilizumab was administered after the onset of ARDS. Conclusion: Early administration of tocilizumab in patients needing oxygen supplementation may be critical to patient recovery. Our preliminary data could inform bedside decisions until more data regarding the precise timing in of initiation of the treatment with tocilizumab.

Antecedentes: Los tratamientos inmunomoduladores para la prevención del daño pulmonar están siendo ampliamente estudiados contra la COVID-19. El objetivo primario es evaluar la mortalidad a los 7 días después de la administración de tocilizumab. El objetivo secundario es el ingreso en UCI, el desarrollo de distrés respiratorio agudo e insuficiencia respiratoria aguda entre otros. Métodos: Informamos sobre los resultados preliminares de la cohorte del Hospital Universitario Vall d'Hebron en Barcelona (España), que incluye todos los pacientes consecutivos con infección confirmada por SARS-CoV-2 y que recibieron tratamiento con tocilizumab hasta el 25 de marzo 2020. Resultados: Ochenta y dos pacientes con COVID-19 recibieron al menos una dosis de tocilizumab. La edad media (±DE) fue de 59,1 (±19,8) años, el 63% eran hombres, 22% correspondía a paciente nacidos fuera de España, y la mediana (RIC) del índice de Charlson ajustado por edad en el momento basal fue de 3 (1-4) puntos. Sesenta y dos pacientes (75,6%) y 45 pacientes (54,9%) desarrollaron insuficiencia respiratoria y distrés respiratorio agudo respectivamente. La mediana de tiempo desde el inicio de los síntomas hasta el desarrollo de ditrés fue de 8 días (5-11). La mortalidad a los 7 días fue del 26,8% La hazard ratio de mortalidad fue del 3,3; IC 95% 1,3-8,5 (la hazard ratio de mortalidad ajustada por edad fue de 2,1; IC 95% 0,8-5,8) si el tocilizumab se administraba después del inicio del distrés respiratorio. Conclusión: La administración precoz de tocilizumab en pacientes con suplementos de oxígeno podría ser crítica para la recuperación de los pacientes. Nuestros datos podrían ayudar a tomar decisiones clínicas hasta que se disponga de más información sobre el momento adecuado para iniciar el tratamiento con tocilizumab.

Early outcomes in adults hospitalized with severe SARS-CoV-2 infection receiving tocilizumab / Resultados preliminares en pacientes adultos con infección grave por SARS-CoV-2 tratados con tocilizumab

Background:Modulation of the immune system to prevent lung injury is being widely used against the new coronavirus disease (COVID-19). The primary endpoint was mortality at 7 days after tocilizumab administration. Secondary endpoints were admission to the intensive care unit, development of ARDS and respiratory insufficiency among others.Methods:We report the preliminary results from the Vall d’Hebron cohort study at Vall d’Hebron University Hospital, in Barcelona (Spain), including all consecutive patients who had a confirmed SARS-CoV-2 infection and who were treated with tocilizumab until March 25th.Results:82 patients with COVID-19 received at least one dose of tocilizumab. The mean (± SD) age was 59.1 (19.8) years, 63% were male, 22% were of non-Spanish ancestry, and the median (IQR) age-adjusted Charlson index at baseline was 3 (1–4) points. Respiratory failure and ARDS developed in 62 (75.6%) and 45 (54.9%) patients, respectively. Median time from symptom onset to ARDS development was 8 (5–11) days. Mortality at 7 days was 26.8%. Hazard ratio for mortality was 3.3; 95% CI, 1.3–8.5 (age-adjusted hazard ratio for mortality 2.1; 95% CI, 0.8–5.8) if tocilizumab was administered after the onset of ARDS.Conclusion:Early administration of tocilizumab in patients needing oxygen supplementation may be critical to patient recovery. Our preliminary data could inform bedside decisions until more data regarding the precise timing in of initiation of the treatment with tocilizumab. (AU)

Antecedentes:Los tratamientos inmunomoduladores para la prevención del daño pulmonar están siendo ampliamente estudiados contra la COVID-19. El objetivo primario es evaluar la mortalidad a los 7 días después de la administración de tocilizumab. El objetivo secundario es el ingreso en UCI, el desarrollo de distrés respiratorio agudo e insuficiencia respiratoria aguda entre otros.Métodos:Informamos sobre los resultados preliminares de la cohorte del Hospital Universitario Vall d’Hebron en Barcelona (España), que incluye todos los pacientes consecutivos con infección confirmada por SARS-CoV-2 y que recibieron tratamiento con tocilizumab hasta el 25 de marzo 2020.Resultados:Ochenta y dos pacientes con COVID-19 recibieron al menos una dosis de tocilizumab. La edad media (±DE) fue de 59,1 (±19,8) años, el 63% eran hombres, 22% correspondía a paciente nacidos fuera de España, y la mediana (RIC) del índice de Charlson ajustado por edad en el momento basal fue de 3 (1-4) puntos. Sesenta y dos pacientes (75,6%) y 45 pacientes (54,9%) desarrollaron insuficiencia respiratoria y distrés respiratorio agudo respectivamente. La mediana de tiempo desde el inicio de los síntomas hasta el desarrollo de ditrés fue de 8 días (5-11). La mortalidad a los 7 días fue del 26,8% La hazard ratio de mortalidad fue del 3,3; IC 95% 1,3-8,5 (la hazard ratio de mortalidad ajustada por edad fue de 2,1; IC 95% 0,8-5,8) si el tocilizumab se administraba después del inicio del distrés respiratorio.Conclusión:La administración precoz de tocilizumab en pacientes con suplementos de oxígeno podría ser crítica para la recuperación de los pacientes. Nuestros datos podrían ayudar a tomar decisiones clínicas hasta que se disponga de más información sobre el momento adecuado para iniciar el tratamiento con tocilizumab. (AU)

Recurrent thrombosis as a clinical presentation of Whipple disease.

Whipple's disease (WD) is a rare infectious disease with a wide clinical spectrum. Associated thrombotic manifestations are not well described in WD, only related to 'stroke-like syndrome'. We present a case of a 39-year-old man with a 1-year history of self-limited episodes of fever, associated with generalised adenopathies and recurrent superficial and deep venous thrombosis events, which have resorted four times despite the anticoagulant treatment. Finally, the patient is diagnosed with WD. Following treatment the patient improved in his general condition, and no more episodes of fever neither thrombosis appeared during a follow-up of more than 3 years.

Incidence and risk factors for early readmission after hospitalization for SARS-CoV-2 infection: results from a retrospective cohort study.

PURPOSE: We aim to assess risk factors related to early readmission in previous hospitalized patients with COVID-19. METHODS: We analyzed a retrospective cohort of patients with laboratory-confirmed COVID-19 admitted to Vall d'Hebron University Hospital, Barcelona, Spain. Early readmission was defined as the need for hospitalization within a period of 60 days after discharge. A descriptive analysis of the readmission was performed, including hospitalization outcome. We also performed a multivariate logistic regression to define risk factors for readmission RESULTS: A total of 629 patients were followed up during 60 days with a readmission cumulative incidence of 5.4% (34 out of 629) and an incidence rate of 0.034 person-years. Main reasons for readmission were respiratory worsening (13, 38.2%), decompensation of previous disease (12, 35.3%) or infectious complications (6, 17.6%). Median time to readmission was 12 days (interquartile range 7-33 days). Prior diagnosis of heart failure (OR 4.09; 95% CI 1.35-12.46; p = 0.013), length of stay during index admission greater than 13 days (OR 2.72; 95% CI 1.21-6.12; p = 0.015), treatment with corticosteroids (OR 2.39; 95% CI 1.01-5.70; p = 0.049) and developing pulmonary thromboembolism (OR 11.59; 95% CI 2.89-46.48; p = 0.001) were the risk factors statistically associated with early readmission. CONCLUSION: Readmission cumulative incidence was 5.4%. Those patients with prior diagnosis of heart failure, length of stay greater than 13 days, treated with corticosteroids or who developed pulmonary thromboembolism might benefit from close monitoring after being discharged.

Early outcomes in adults hospitalized with severe SARS-CoV-2 infection receiving tocilizumab.

BACKGROUND: Modulation of the immune system to prevent lung injury is being widely used against the new coronavirus disease (COVID-19). The primary endpoint was mortality at 7 days after tocilizumab administration. Secondary endpoints were admission to the intensive care unit, development of ARDS and respiratory insufficiency among others. METHODS: We report the preliminary results from the Vall d'Hebron cohort study at Vall d'Hebron University Hospital, in Barcelona (Spain), including all consecutive patients who had a confirmed SARS-CoV-2 infection and who were treated with tocilizumab until March 25th. RESULTS: 82 patients with COVID-19 received at least one dose of tocilizumab. The mean (± SD) age was 59.1 (19.8) years, 63% were male, 22% were of non-Spanish ancestry, and the median (IQR) age-adjusted Charlson index at baseline was 3 (1-4) points. Respiratory failure and ARDS developed in 62 (75.6%) and 45 (54.9%) patients, respectively. Median time from symptom onset to ARDS development was 8 (5-11) days. Mortality at 7 days was 26.8%. Hazard ratio for mortality was 3.3; 95% CI, 1.3-8.5 (age-adjusted hazard ratio for mortality 2.1; 95% CI, 0.8-5.8) if tocilizumab was administered after the onset of ARDS. CONCLUSION: Early administration of tocilizumab in patients needing oxygen supplementation may be critical to patient recovery. Our preliminary data could inform bedside decisions until more data regarding the precise timing in of initiation of the treatment with tocilizumab.

An overview of cilastatin + imipenem + relebactam as a therapeutic option for hospital-acquired and ventilator-associated bacterial pneumonia: evidence to date.

Introduction: Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) are prevalent nosocomial infections with a worrisomely increasing prevalence of multidrug-resistant causative organisms, including those with resistance to carbapenems. The addition of relebactam, a ß-lactamase inhibitor, to imipenem treatment restores the antimicrobial activity against the most of multidrug-resistant Gram-negative bacteria, including some carrying ß-lactamase enzyme-type carbapenemases.Areas covered: The aim of this article is to summarize the current evidence regarding imipenem/relebactam for the treatment of HAP/VAP. The authors discuss its chemistry, pharmacokinetics/pharmacodynamics, microbiology, tolerance and clinical efficacy. The results of clinical trials have demonstrated an efficacy of imipenem/relebactam similar to that of its comparator for the treatment of patients with HAP/VAP. Different studies have also shown its good safety profile, which is better than that of the combination of other ß-lactams with other antibiotics.Expert opinion: This drug should be incorporated as a new therapeutic option for the treatment of patients with HAP/VAP, especially as an alternative treatment in patients with confirmed infections caused by multidrug-resistant Gram-negatives.