A subcutaneous insulin pharmacokinetic model for insulin Detemir

Utilization of Pharmacokinetic/Pharmacodynamic Modeling in Pharmacoepidemiological Studies: A Systematic Review on Antiarrhythmic and Glucose-Lowering Medicines

Introduction: In human pharmacology, there are two important scientific branches: clinical pharmacology and pharmacoepidemiology. Pharmacokinetic/pharmacodynamic (PK/PD) modeling is important in preclinical studies and randomized control trials. However, it is rarely used in pharmacoepidemiological studies on the effectiveness and medication safety where the target population is heterogeneous and followed for longer periods. The objective of this literature review was to investigate how far PK/PD modeling is utilized in observational studies on glucose-lowering and antiarrhythmic drugs.

Method: A systematic literature search of MEDLINE, Embase, and Web of Science was conducted from January 2010 to 21 February 2020. To calculate the utilization of PK/PD modeling in observational studies, we followed two search strategies. In the first strategy, we screened a 1% random set from 95,672 studies on glucose-lowering and antiarrhythmic drugs on inclusion criteria. In the second strategy, we evaluated the percentage of studies in which PK/PD modeling techniques were utilized. Subsequently, we divided the total number of included studies in the second search strategy by the total number of eligible studies in the first search strategy.

Results: The comprehensive search of databases and the manual search of included references yielded a total of 29 studies included in the qualitative synthesis of our systematic review. Nearly all 29 studies had utilized a PK model, whereas only two studies developed a PD model to evaluate the effectiveness of medications. In total, 16 out of 29 studies (55.1%) used a PK/PD model in the observational setting to study effect modification. The utilization of PK/PD modeling in observational studies was calculated as 0.42%.

Conclusion: PK/PD modeling techniques were substantially underutilized in observational studies of antiarrhythmic and glucose-lowering drugs during the past decade.

Exploration of temperature and shelf-life dependency of the therapeutically available Insulin Detemir

PURPOSE

Insulin, in typical use, undergoes multiple changes in temperature; from refrigerator, to room temperature, to body temperature. Although long-term storage temperature has been well-studied, the short term changes to insulin are yet to be determined. Insulin detemir (IDet) is a clinically available, slow-acting, synthetic analogue characterised by the conjugation of a C14 fatty acid. The function of this modification is to cause the insulin to form multi-hexameric species, thus retarding the pharmacokinetic rate of action. In this investigation, the temperature dependence properties of this synthetic analogue is probed, as well as expiration.

METHODS

Dynamic light scattering (DLS) and viscometry were employed to assess the effect of temperature upon IDet. Mass spectrometry was also used to probe the impact of shelf-life and the presence of certain excipients.

RESULTS

IDet was compared with eight other insulins, including human recombinant, three fast-acting analogues and two other slow-acting analogues. Of all nine insulins, IDet was the only analogue to show temperature dependent behaviour, between 20 °C and 37 °C, when probed with non-invasive backscatter dynamic light scattering. Upon further investigation, IDet observed significant changes in size related to temperature, direction of temperature (heated/cooled) and expiration with cross-correlation observed amongst all 4 parameters.

CONCLUSIONS

These findings are critical to our understanding of the behaviour of this particular clinically relevant drug, as it will allow the development of future generations of peptide-based therapies with greater clinical efficacy.

Determining the effects of insulin Detemir on endogenous secretion of insulin

Type 2 diabetes (T2D) is a long-term metabolic disorder. A pilot trial was designed to investigate the effects of the long acting insulin Detemir on endogenous insulin secretion, to assess use in early T2D care. Provesn metabolic system models are used to identify patient-specific insulin sensitivity and endogenous insulin secretion from clinical data. Post-cardiac surgery patients with early T2D or pre-diabetes based on HbA1c were given a bolus of insulin Detemir on one day, and none on the second day in hospital. Blood glucose, insulin, C-Peptide, and all nutrition given are recorded. Early results from N=3 patients show 0.8-1.0U/hour insulin Detemir doses have no apparent suppression of endogenous insulin secretion, but does help lower glucose levels. The results show the model captures glucose-insulin dynamics in pre-diabetic post-surgical patients, and insulin Detemir may be useful to support individuals with pre-diabetes in reducing blood glucose levels. Tests with higher doses, need to be carried out to verify these results over a greater range of patients.