Therapeutic Drug Monitoring of Anti-infective Drugs: Implementation Strategies for 3 Different Scenarios

Abstract

Background: Therapeutic drug monitoring (TDM) supports personalized treatment. For successful implementation, TDM must have a turnaround time suited to the clinical needs of patients and their health care settings. Here, the authors share their views of how a TDM strategy can be tailored to specific settings and patient groups.Methods: The authors selected distinct scenarios for TDM: highrisk, complex, and/or critically ill patient population; outpatients; and settings with limited laboratory resources. In addition to the TDM scenario approach, they explored potential issues with the legal framework governing dose escalation. Results:The most important issues identified in the different scenarios are that critically ill patients require rapid turnaround time, outpatients require an easy sampling procedure for the sample matrix and sample collection times, settings with limited laboratory resources necessitate setting-specific analytic techniques, and all scenarios warrant a legal framework to capture the use of escalated dosages, ideally with the use of trackable dosing software. Conclusions:To benefit patients, TDM strategies need to be tailored to the intended population. Strategies can be adapted for rapid turnaround time for critically ill patients, convenient sampling for outpatients, and feasibility for those in settings with limited laboratory resources.

Clinical standards for the dosing and management of TB drugs

“…As drug exposure reflects all these underlying factors, TDM may be recommended in patients not responding to treatment when available ( Figure 1 ). 51 – 54 …”

“… 53 , 82 The implementation of TDM can be tailored for specific TB services making use of various types of assays (e.g., high-performance liquid chromatography-ultraviolet, liquid chromatography–mass spectrometry or nanophotometer). 54 , 83 Dose changes guided by TDM should take other clinical parameters into consideration (e.g., severe cavitary disease). 47 High priority populations to consider for TDM include those with HIV co-infection, DM, malnutrition, or children, because these factors increase the probability of pharmacokinetic variability and are independently associated with poor TB treatment outcomes ( Figure 1 ).…”

“…Finally, the central level should be able to provide training modules for other levels, a quality assurance programme 107 and advanced quantitative assays, 112 including multiple sample matrices (blood, DBS, saliva, urine) to facilitate the analysis of samples by mail from rural areas or other outpatient settings and also provide dosing software to calculate the drug dose for optimal exposure. 54 …”

Alternative Methods for Therapeutic Drug Monitoring and Dose Adjustment of Tuberculosis Treatment in Clinical Settings: A Systematic Review

“…However, TDM poses many challenges such as uncomfortable sampling methods, requirement for highly trained personnel from the sample collection to analysis, and dry-ice shipping, which all lead to high costs or a lack of availability in TB-endemic settings where poor treatment outcomes are more common and TDM may be of the most benefit [6]. Performing TDM with dried blood spots (DBS), urine, saliva, and hair, in lieu of regular serum or plasma sampling is gaining popularity owing to the relatively simple sample collection and specimens that do not require cold-chain transport [7,8].…”

Special Issue on the Therapeutic Drug Monitoring of Anti-infective Drugs: Editorial

“…The TDM approach should be tailored to the specific situation, with a more rapid turnaround time being more important for a population with critical illness than for one with a chronic condition that requires months of or even lifelong therapy. By selecting 3 distinct scenarios for TDM (critically ill patients, outpatients, and remote settings with limited laboratory resources), Kim et al 13 demonstrated that for optimal benefit, TDM strategies must be appropriate for the intended population. For example, the rapid turnaround time for critically ill patients, convenient sampling for outpatients, and feasibility and availability for those in settings with limited laboratory resources proved to be important factors.…”