Lower-dose prescriptions in the post-marketing situation and the influencing factors thereon

The impacts of undetected nonadherence in phase II, III and post-marketing clinical trials: An overview

AIMS

This research aims to provide an overview of the consequences of undiagnosed nonadherence (noninitiation, suboptimal implementation, nonpersistence) in randomized clinical trials (RCTs).

METHODS

This research was conducted by combining a literature review and qualitative semistructured interviews with key opinion leaders. Based on this groundwork, the consequences of undiagnosed nonadherence in RCTs were summarized and reported in a figure. This study focused on phases II, III and post-marketing in ambulatory settings across a variety of therapeutic areas and indications.

RESULTS

Various consequences of nonadherence in RCTs were investigated. In phase II, drug efficacy may be underestimated, variability in the outcomes may be high and a distorted picture of side effects could be reported, resulting in an uncertain impression of the investigational product's profile and complicating decision-making. The sponsor may need to increase the sample size of the upcoming phase III study to improve its power, representing additional costs, or even terminate the study. In phase III, similar phenomena may be observed, making demonstration of efficacy to the regulatory bodies more difficult. Lastly, after commercialization, a distortion in pharmacometrics may occur: the drug may underperform, prescriptions may be refilled less often than expected or extra expenses may be incurred by the payers. This can result in post-marketing dose reduction, new competitors coming into the market and, eventually, product withdrawal.

CONCLUSIONS

This research highlighted the many potential adverse consequences of undiagnosed nonadherence in RCTs, including additional costs. Collecting accurate data appeared to be crucial for decision-making throughout the drug development process.

Physician and patient adherence in hypertension trials: a point of view on an important issue to resolve

INTRODUCTION

Randomized controlled trials (RCTs) are important sources of evidence that strongly influence guidelines for patient management, including for elevated blood pressure in adults.

AREAS COVERED

Critical questions regarding the interpretation of hypertension trial results have recently increased, especially for concerns over methodology. In particular, investigator adherence to the protocol and patient adherence to investigational drugs are often far from optimal. These issues may be ignored or underreported because physicians' behavior during trials is often not monitored and patients' medication adherence is neither measured adequately nor reported or analyzed in the final report or in the publication. This situation may lead to misinterpretations of study results and misevaluations of the safety and efficacy profile of new drugs. In this short review, the problem of measuring, reporting, and analyzing drug adherence in RCTs is discussed and illustrated with several examples in the field of hypertension.

EXPERT OPINION

The main conclusion is that drug adherence should always be measured in clinical trials, possibly with more than one method. In addition, prespecified analyses of adherence data should be included in the statistical plan of all trials to improve their overall quality.

The Importance of Assessing Drug Exposure and Medication Adherence in Evaluating Investigational Medications: Ensuring Validity and Reliability of Clinical Trial Results

The objective of this current opinion paper is to draw global attention to medication adherence, emphasizing its crucial role in drug trials. Frequently, trialists lean on traditional approaches to assess medication adherence, which, while comfortable, may only reveal what trialists desire rather than offering the essential insights needed for informed decision making in drug development. Understanding drug exposure and medication adherence is paramount when evaluating the effectiveness and safety of investigational medications. Without a comprehensive understanding of how patients adhere to their prescribed treatment regimens, the integrity and dependability of clinical trial results can be compromised. This paper emphasizes the need for measures that accurately and reliably assess medication intake behaviors, enabling the differentiation between minor dosing errors and significant deviations that may impact the drug's efficacy and safety. Accurate knowledge of drug exposure empowers researchers to make informed decisions, identify potential confounding factors, and appropriately interpret study outcomes, ultimately ensuring the validity and reliability of the research findings. By prioritizing drug exposure assessment and medication adherence measurement, clinical trials can enhance their scientific rigor, contribute to more accurate evaluations of investigational medications, and ultimately speed up the development process.

Italian Real-World Analysis of a Tyrosine Kinase Inhibitor Administration as First- or Second-Line of Therapy in Patients with Chronic Myeloid Leukemia

PURPOSE

To date, litte evidence is reported about the real-life dosage of tyrosine kinase inhibitors prescribed in Italy. The present observational retrospective study aimed to evaluate the mean daily dose of nilotinib prescribed as first- and second-line therapy among patients suffering from chronic myeloid leukemia (CML) in settings of clinical practice in Italy.

PATIENTS AND METHODS

Data were obtained from the administrative databases of a sample of Italian entities. All adult patients prescribed nilotinib were included from January 2013 to December 2016 if they were using it as first-line and from January 2015 to December 2018 as second-line therapy. The mean daily dose was calculated considering the dosage between first and last nilotinib prescription date or last BCR/ABL test date.

RESULTS

Among CML patients treated with nilotinib as first-line (N=87), the mean daily dose of nilotinib was 500.5 mg during a mean treatment duration of 798.9 days and of 498.54 mg considering the last determination of BCR/ABL test (mean duration of 811 days). A total of 103 CML patients were prescribed nilotinib as second-line therapy; of them, 80.6% had previously received imatinib, 17.5% dasatinib. The mean daily dose of nilotinib was found to be 566.3 mg with a mean time duration of 302.8 days, while when the last BCR/ABL test was taken into account (mean duration of 323.1 days), a mean daily dose of 565.2 mg was detected.

CONCLUSION

The study reported on the real-world dosage pattern of a TKI for CML management. Our results compared with the dosage of nilotinib reported in datasheet (600 mg and 800 mg for first- and second-line, respectively) showed a trend of mean daily dose prescribed in clinical practice settings lower than the dosage currently indicated.

[Relationship between Dose Discontinuation or Dose Reduction for Safety Reasons in Clinical Trials and Lower-dose Prescriptions in the Post-marketing Setting]

Dosage of pharmaceuticals is determined and approved based on pivotal clinical trial results in Phase 3. However, in the post-marketing setting, it is often adjusted according to conditions of individual patients. Some pharmaceuticals are used at a lower dose than the approved dose for safety reasons or in elderly patients. In this study, we examined the relationships between dose discontinuation or dose reduction, for safety reasons as well as participation of elderly patients in clinical trials, and lower-dose prescriptions in the post-marketing setting. We collated the dataset of 113 eligible pharmaceuticals from those that were approved in Japan between 2005 and 2014. Subsequently, we calculated the proportions of patients who withdrew from the study, whose medication was discontinued, or dose reduced due to adverse events, and of elderly patients (over sixty-five years old) to those who were exposed to the approved dose range in the pivotal clinical trials. Then their relationships with lower-dose prescription in the post-marketing setting were examined using Mann-Whitney U test. The proportions of patients who withdrew from the study (p=0.0019), whose medication was discontinued owing to adverse events (p=0.0007), or whose dose was reduced owing to adverse events (p<0.0001) were significantly higher for "lower-dose prescription drugs" than those for other drugs; however, the proportion of elderly patients did not show this significant increase in the "lower-dose prescription drugs" group.

The influence of ACE inhibitors and ARBs on hospital length of stay and survival in people with COVID-19

OBJECTIVE

During the COVID-19 pandemic the continuation or cessation of angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARBs) has been contentious. Mechanisms have been proposed for both beneficial and detrimental effects. Recent studies have focused on mortality with no literature having examined length of hospital stay. The aim of this study was to determine the influence of ACEi and ARBs on COVID-19 mortality and length of hospital stay.

METHODS

COPE (COVID-19 in Older People) is a multicenter observational study including adults of all ages admitted with either laboratory or clinically confirmed COVID-19. Routinely generated hospital data were collected. Primary outcome: mortality; secondary outcomes: Day-7 mortality and length of hospital stay. A mixed-effects multivariable Cox's proportional baseline hazards model and logistic equivalent were used.

RESULTS

1371 patients were included from eleven centres between 27th February to 25th April 2020. Median age was 74 years [IQR 61-83]. 28.6% of patients were taking an ACEi or ARB. There was no effect of ACEi or ARB on inpatient mortality (aHR = 0.85, 95%CI 0.65-1.11). For those prescribed an ACEi or ARB, hospital stay was significantly reduced (aHR = 1.25, 95%CI 1.02-1.54, p = 0.03) and in those with hypertension the effect was stronger (aHR = 1.39, 95%CI 1.09-1.77, p = 0.007).

CONCLUSIONS

Patients and clinicians can be reassured that prescription of an ACEi or ARB at the time of COVID-19 diagnosis is not harmful. The benefit of prescription of an ACEi or ARB in reducing hospital stay is a new finding.