Comparison between a single dose of PEG G-CSF and multiple doses of non-PEG G-CSF: a systematic review and meta-analysis from Clinical Practice Guidelines for the use of G-CSF 2022

BACKGROUD

Granulocyte colony-stimulating factor (G-CSF) is widely used for the primary prophylaxis of febrile neutropenia (FN). Two types of G-CSF are available in Japan, namely G-CSF chemically bound to polyethylene glycol (PEG G-CSF), which provides long-lasting effects with a single dose, and non-polyethylene glycol-bound G-CSF (non-PEG G-CSF), which must be sequentially administrated for several days.

METHODS

This current study investigated the utility of these treatments for the primary prophylaxis of FN through a systematic review of the literature. A detailed literature search for related studies was performed using PubMed, Ichushi-Web, and the Cochrane Library. Data were independently extracted and assessed by two reviewers. A qualitative analysis or meta-analysis was conducted to evaluate six outcomes.

RESULTS

Through the first and second screenings, 23 and 18 articles were extracted for qualitative synthesis and meta-analysis, respectively. The incidence of FN was significantly lower in the PEG G-CSF group than in the non-PEG G-CSF group with a strong quality/certainty of evidence. The differences in other outcomes, such as overall survival, infection-related mortality, the duration of neutropenia (less than 500/μL), quality of life, and pain, were not apparent.

CONCLUSIONS

A single dose of PEG G-CSF is strongly recommended over multiple-dose non-PEG G-CSF therapy for the primary prophylaxis of FN.

Sequential dosing of convalescent COVID-19 plasma with significant temporal clinical improvements in a persistently SARS-COV-2 positive patient

The current global pandemic, SARS-CoV-2 infection, is still extending across the world affecting millions of lives to the date. While new successful vaccines are available with promising outcomes to minimize the spread and to reduce the severity of the disease, optimal therapeutic options still remain elusive. COVID-19 convalescent plasma (CCP) is an investigational treatment option which studies suggesting signals of efficacy and favorable outcomes only for patients treated very early in course of the disease. Benefits of the use of CCP later in the disease remain highly debated and therefore are not common practice. We hereby report a case of severe SARS-CoV-2 infection in a young male patient with prolonged COVID-19 positivity who received repeat doses of CCP treatments later in the disease with temporal clinical improvement. This patient's case highlights the need of further studies evaluating efficacy of repeated dosing of CCP. This also suggests a potential of successful use of CCP later in the disease in selected COVID-19 patients.

Repeated infusion of mesenchymal stem cells maintain the condition to inhibit deteriorated motor function, leading to an extended lifespan in the SOD1G93A rat model of amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative fatal disorder in which motor neurons within the brain and spinal cord degenerate. A single infusion of mesenchymal stem cells (MSCs) delays disease progression by protecting motor neurons and restoring the blood-spinal cord barrier in the SOD1G93A transgenic ALS rat model. However, the therapeutic effect of a single infusion of MSCs is transient and does not block disease progression. In this study, we demonstrated that repeated administration of MSCs (weekly, four times) increased the survival period, protected motor functions, and reduced deterioration of locomotor activity compared to a single infusion and vehicle infusion, after which rats displayed progressive deterioration of hind limb function. We also compared the days until gait ability was lost in rats and found that the repeated-infused group maintained gait ability compared to the single-infusion and vehicle-infusion groups. These results suggest that repeated administration of MSCs may prevent the deterioration of motor function and extend the lifespan in ALS.

Comparison of One and Three Intraventricular Injections of Cardiac Progenitor Cells in a Murine Model of Chronic Ischemic Cardiomyopathy

Repeated doses of c-kit⁺ cardiac progenitor cells (CPCs) are superior to a single dose in improving LV function in rats with old myocardial infarction (MI). However, this concept needs testing in different species to determine whether it is generalizable. We used a new murine model of chronic ischemic cardiomyopathy whose unique feature is that cell therapy was started late (3 months) after MI. Mice received three echo-guided intraventricular infusions, 5 weeks apart, of vehicle, CPCs × 1, or CPCs × 3. Echocardiography demonstrated that the single-dose group exhibited improved LV ejection fraction (EF) after the 1st infusion (CPCs), but not after the 2nd and 3rd (vehicle). In contrast, in the multiple-dose group LVEF continued to improve, so that the final value was greater than in vehicle or single-dose groups (P < 0.05). Hemodynamic studies showed that compared with vehicle, both preload-dependent and preload-independent functional parameters were significantly increased in the multiple-dose group but not in the single-dose group. Thus, two independent methods of functional assessment (echocardiography and hemodynamic studies) consistently demonstrated the superiority of three doses of CPCs vs. one dose. Compared with the single-dose group, the multiple-dose group exhibited less LV hypertrophy, as evidenced by a greater reduction in LV/body weight ratio and cardiomyocyte cross-sectional area. Furthermore, unlike the single dose, three CPC doses reduced myocardial inflammatory cells in the risk region. This is the first study of echo-guided intraventricular infusion of CPCs in mice with chronic ischemic cardiomyopathy. The results demonstrate that the beneficial effects of three CPC doses are greater than those of one dose, supporting the concept that multiple treatments are necessary to properly evaluate cell therapy. Our findings indicate that this concept applies not only to rat models but also to murine models. The generalizability of this strategy greatly enhances its importance and provides a rationale for large animal studies. Graphical abstract.

A Stochastic Model for the Ethanol Pharmacokinetics

BACKGROUND

The aim of this study was to propose a new stochastic model to study the time course of ethanol elimination in human bodies.

METHODS

The times and amount of alcohol ingested are assumed to be random in controllable intervals. Constant elimination rate follows zero order kinetics and is replaced by first order kinetics when the effects of alcohol increase due to alcohol ingestion. Simulation studies of three different models were made to compare the statistical characteristics of the ethanol effects obtained using analytical expressions. For each model, three cases were considered depending on the drinking pattern and by classifying the drinker as heavy, normal or sparse.

RESULTS

From the model formulation, we noted that as the rate of drinking increases for a given elimination rate, the expected time between overflows goes towards zero. Furthermore, as the average amount of alcohol in each drink increases, the corresponding time between overflows decreases.

CONCLUSION

Variations in times of alcohol intakes as well as the amount of alcohol consumption can be accounted through the final created formula. The model proves that overflows occur when alcohol is ingested before the adverse effects of alcohol from the previous drink are completely eliminated. Being the first stochastic model of such a kind, we do hope that it will throw more light on interpreting experimental data of alcohol abuse.

Variability and singularity arising from poor compliance in a pharmacokinetic model II: the multi-oral case

We propose a stochastic model for the drug concentration in the case of multiple oral doses and in a situation of poor patient adherence. Our model is able to take into account an irregular drug intake schedule. This article is the second in a series of three. It presents a multi-oral version of the results given in Lévy-Véhel and Lévy-Véhel (J Pharmacokinet Pharmacodyn 40(1):15-39, 2013), that dealt with the multi-IV bolus case. Under the assumption that the irregular dosing schedule follows a Poisson law, we study features of the drug concentration that have practical implications, such as its variability and the regularity of its cumulative probability distribution, which describes its predictive power with respect to the mean behaviour. We consider four variants: continuous-time, with either deterministic or random doses, and discrete-time, also with either deterministic or random doses. Our computations allow one to assess in a precise way the effect of various significant parameters such as the mean rate of intake, the elimination rate, the absorption rate and the mean dose. They quantify how much poor adherence will affect the efficacy of therapy. To appreciate this impact, we provide detailed comparisons with the variability of concentration in two reference situations: a fully adherent patient and a population of fully adherent patients with log-normally distributed pharmacokinetic parameters. Besides, the discrete-time versions of our models reveal unexpected links with objects which have been studied in the mathematical literature under the name of infinite Bernoulli convolutions (Erdós, Am J Math 61:974-975, 1939). This allows us to quantify the fact that, when the random dosing schedule is too sparse, the concentration behaves in a very erratic way. Our results complement the ones in Lévy-Véhel and Lévy-Véhel (J Pharmacokinet Pharmacodyn 40(1):15-39, 2013) and help understanding the consequences of poor adherence. They may have practical outcomes in terms of drug dosing and scheduling.

Pharmacokinetics, safety, and tolerability of rotigotine transdermal system in healthy Japanese and Caucasian subjects following multiple-dose administration

Rotigotine is a dopamine receptor agonist indicated for the treatment of Parkinson's disease and moderate-to-severe restless legs syndrome. Continuous transdermal delivery of rotigotine via a silicon-based patch maintains stable plasma concentrations over 24 h. The objective of the study was to evaluate the pharmacokinetics, safety, and tolerability of a multiple-dose schedule of rotigotine transdermal patch in Japanese and Caucasian subjects. In this open-label, repeated-dose, parallel-group study (ClinicalTrials.gov: NCT01854216), healthy male and female subjects of Japanese or Caucasian ethnic origin were matched by gender, body mass index, and age. Subjects underwent a 9-day patch application period. 12 Japanese and 12 Caucasian subjects were included in the pharmacokinetic analyses. Mean apparent doses (actual amount of drug delivered) increased proportionally with rotigotine nominal dosages (1, 2, and 4 mg/24 h) and were similar for both ethnic groups, with large inter-individual variability. Mean plasma concentration-time profiles for unconjugated rotigotine were similar in both ethnic groups at day 3 for each dosage. Peak concentrations (C max,ss) and area under the concentration-time curves from pre-dose to the concentration measured 24 h after administration of patch (AUC(0-24,ss)) showed similar exposure in both groups; higher values in Japanese subjects were explained by differences in body weight. For total rotigotine, C max,ss and AUC(0-24,ss) values were higher in Caucasian subjects and could be explained by small differences in apparent dose. Rotigotine was generally well tolerated following multiple applications up to 4 mg/24 h. These findings suggest similar dosage requirements for rotigotine transdermal system in Japanese and Caucasian populations.