Peg-Asparaginase-Associated Pancreatitis in Chemotherapy-Treated Pediatric Patients: A 5-Year Retrospective Study

Research progress on the PEGylation of therapeutic proteins and peptides (TPPs)

With the rapid advancement of genetic and protein engineering, proteins and peptides have emerged as promising drug molecules for therapeutic applications. Consequently, there has been a growing interest in the field of chemical modification technology to address challenges associated with their clinical use, including rapid clearance from circulation, immunogenicity, physical and chemical instabilities (such as aggregation, adsorption, deamination, clipping, oxidation, etc.), and enzymatic degradation. Polyethylene glycol (PEG) modification offers an effective solution to these issues due to its favorable properties. This review presents recent progress in the development and application of PEGylated therapeutic proteins and peptides (TPPs). For this purpose, firstly, the physical and chemical properties as well as classification of PEG and its derivatives are described. Subsequently, a detailed summary is provided on the main sites of PEGylated TPPs and the factors that influence their PEGylation. Furthermore, notable instances of PEG-modified TPPs (including antimicrobial peptides (AMPs), interferon, asparaginase and antibodies) are highlighted. Finally, we propose the chemical modification of TPPs with PEG, followed by an analysis of the current development status and future prospects of PEGylated TPPs. This work provides a comprehensive literature review in this promising field while facilitating researchers in utilizing PEG polymers to modify TPPs for disease treatment.

Hyperamylasemia Caused by the Hantaan Virus: A Retrospective Study of 101 Patients with Hemorrhagic Fever with Renal Syndrome in West China

Background. Hyperamylasemia (HA) is an inconspicuous manifestation of hemorrhagic fever with renal syndrome (HFRS) in Baoji city, West China. Hantaan virus (HTNV) is the only pathogen-caused HFRS in this region, but the knowledge about HA in the local HFRS patients has been limited. The aim of this study was to investigate the characteristics of HA and its predictive risk factors for doctors to engage in timely monitoring and dealing with the possible serious changes prewarned by HA in the early stages of the disease to improve the final outcome. Methods. All HFRS patients with and without HA (HA and nHA groups, respectively) were treated in Baoji People’s Hospital. The clinical characteristics between the two groups were compared by Student’s $\mathit{t}$ -test or Chi-square test. The risk factors for prognosis were measured by the logistic regression analysis. The predictive effects of prognosis in clinical and laboratory parameters were analyzed by the receiver operating characteristic curves. Results. 46.53% of the patients demonstrated HA, among which 71.7% were severe and critical types of HFRS, greater than that in the nHA group (19.57%, $\mathit{P}<\mathbf{0.001}$ ). The hospitalization day and the general incidence of acute pancreatitis (AP) were longer or greater in the HA group than in the nHA group ( $\mathit{P}<\mathbf{0.01}$ ). Age and the time from the onset of the first symptom to the patient being admitted to hospital ( $T_{\text{OA}}$ ) were the predictive risk factors for HA. The best cut-off values were the age of 54 years and $T_{\text{OA}}$ of 5.5 days. Conclusion. HTNV-induced HA is a common clinical presentation of HFRS patients in West China. It can increase the severity, the hospitalization days of patients, and the incidence of AP in HFRS. Age and $T_{\text{OA}}$ constituted independent risk factors for HA caused by HTNV.

Demographics and risk factors for pediatric recurrent acute pancreatitis

PURPOSE OF REVIEW

Approximately 20-30% of children who experience one episode of acute pancreatitis will have at least one additional episode. For some children, pancreatitis recurs multiple times and in a few years is followed by the diagnosis of chronic pancreatitis. Identifying risk factors for recurrent episodes and disease progression is critical to developing therapeutic interventions.

RECENT FINDINGS

Obesity is driving an increase in biliary stone disease and severe acute pancreatitis. Recurrent acute pancreatitis (RAP) may lead to the development of diabetes through autoimmune mechanisms. Cystic fibrosis or CFTR-related disorders may present as RAP and CFTR modulator therapy can increase or decrease the risk of acute pancreatitis in these populations. Children with Crohn disease have a three-fold risk of acute pancreatitis over the general population while children with ulcerative colitis are at increased risk for pediatric autoimmune pancreatitis, a disorder that may be distinct from autoimmune pancreatitis described in adults. Obstructive jaundice in the absence of identified mechanical factors may be a presenting sign of pediatric autoimmune pancreatitis.

SUMMARY

Pediatric RAP is a painful condition that leads to gland destruction and functional insufficiency. Risk factors are being clarified but preventive treatments remain elusive.

Technological Prospecting: Mapping Patents on L-asparaginases from Extremophilic Microorganisms

BACKGROUND

L-asparaginase (L-ASNase, L-asparagine amidohydrolase, E.C.3.5.1.1) is an enzyme with wide therapeutic applicability. Currently, the commercialized L-ASNase comes from mesophilic organisms, presenting low specificity to the substrate and limitations regarding thermostability and active pH range. Such factors prevent the maximum performance of the enzyme in different applications. Therefore, extremophilic organisms may represent important candidates for obtaining amidohydrolases with particular characteristics desired by the biotechnological market.

OBJECTIVES

The present study aims to carry out a technological prospecting of patents related to the L-asparaginases derived from extremophilic organisms, contributing to pave the way for further rational investigation and application of such enzymes.

METHODS

This patent literature review used six patents databases: The LENS, WIPO, EPO, USPTO, Patent Inspiration, and INPI.

RESULTS

It was analyzed 2860 patents, and 14 were selected according to combinations of descriptors and study criteria. Approximately 57.14% of the patents refer to enzymes obtained from archaea, especially from the speciesPyrococcus yayanosii (35.71% of the totality).

CONCLUSION

The present prospective study has singular relevance since there are no recent patent reviews for L-asparaginases, especially produced by extremophilic microorganisms. Although such enzymes have well-defined applications, corroborated by the patents compiled in this review, the most recent studies allude to new uses, such as the treatment of infections. The characterization of the catalytic profiles allows us to infer that there are potential sources still unexplored. Hence, the search for new L-ASNases with different characteristics will continue to grow in the coming years and, possibly, ramifications of the technological routes will be witnessed.

Adverse Reactions to Drugs of Special Interest in a Pediatric Oncohematology Service

Introduction: Drugs used in oncological diseases are frequently related to adverse drug reactions (ADR). Few studies have analyzed the toxicity of cancer treatments in children in real practice.

Methods: An observational, longitudinal and prospective study has been carried out in an Oncohematology Service of a tertiary hospital. During 2017, patients exposed to one or more drugs of a previously agreed list were identified and followed-up for at least 6 months each. Characteristics of ADR, incidence, causality and possible preventability, have been evaluated.

Results: 72 patients have been treated with at least one study drug, and 159 ADR episodes involving at least one of these drugs have been identified, with a total of 293 ADR. Most episodes required hospital admission (35.2%) or happened during the hospital stay (33%), and 91.2% were severe. Blood disorders were the most frequent ADR (96; 32.8%), related to thioguanine (42) and pegaspargase (39) mainly, followed by infections (86; 29.4%) related to thioguanine (32), pegaspargase (27), Erwinia asparaginase (14) and rituximab (13). Two ADR were unknown. Most ADR were dose-dependent or expectable (>90%). The global incidence of ADR was 3.1/100 days at risk (95% CI 2.7–3.5), with 3.5 ADR/100 days at risk with pegaspargase (95% CI 2.9–4.2), 1.2/100 days at risk with rituximab (95% CI 0.8–1.8) and 11.6/100 days at risk with thioguanine (95% CI 9.4–14.2). Controversial additional measures of prevention, other than those already used, were identified.

Conclusion: ADR are frequent in pediatric oncohematological patients, mainly blood disorders and infectious diseases. Findings regarding incidence and preventability may be useful to compare data between different centers and to evaluate new possibilities for action or prevention.