Pharmacist intervention reduces prescribing errors of investigational drugs in cancer clinical trials

A pharmacist intervention appears to be effective in lowering and preventing the incidence of prescribing errors of investigational drugs in oncology clinical trials, a recent study has shown.

“The investigational drug service (IDS) pharmacist intervention in cancer clinical trials was associated with significant reductions in prescribing errors and may lead to increased medication safety,” the researchers said.

To assess the effectiveness of a pharmacist intervention in reducing prescribing errors of investigational drugs for cancer patients, a retrospective study was conducted during two periods: a baseline period from December 2015 to June 2016 and an intervention period from July 2016 to February 2017. Active interventions were carried out by IDS pharmacists during the intervention period. Three models were also generated for the multivariate analysis to identify factors affecting prescribing errors.

A total of 12,387 investigational orders were included, among which 395 (6.1 percent) prescribing errors were identified in 6,477 orders at the baseline period and 278 (4.7 percent) in 5,910 orders at the intervention period. Sponsor initiated trial (SIT) was the strongest factor (adjusted odds ratio, 4.16, 95 percent confidence interval, 3.31–5.23) affecting prescribing errors. [J Pharm Pract 2020;26:29-35]

In all three constructed models, prescribing errors decreased by at least 25 percent with pharmacist intervention after adjusting for confounding variables. Prescribing errors were 1.3 times more frequent when dealing with intravenous vs oral medications. The blinded study had 60-percent fewer prescribing errors compared with the open study.

On the other hand, prescribing errors were 4.2 and 2.4 times higher in SIT and multicentre/multination studies, respectively, than in investigator-initiated trials. There were fewer errors detected in phase II and trials covering both phase I and II than in phase III trials.

“In this study, prescribing error rates decreased from 6.10 percent during the baseline period to 4.70 percent with pharmacist intervention, meaning that IDS pharmacist intervention in cancer clinical trials improved medication safety and promoted adherence to protocol,” the researchers said.

These results were consistent with other clinical studies, showing that pharmacist intervention reduced prescribing errors by 4.1–17.7 percent. Another study reported improved prescription appropriateness by 4.5 percent when pharmacists provided an educational and informative programme to physicians. [J Am Pharm Assoc 2015;55:238-245; Acta Paediatr 2009;98:782-785; Eur J Hosp Pharm 2015;22:198-201]

“The reduction of prescribing errors in this study is somewhat lower than in other pharmacist intervention studies,” the researchers said. “However, the reduction … is meaningful, since prescribing errors in clinical trials can have a greater impact on patient safety and can lead to the success or failure of trials.”

The most common error was the order of wrong medication kit number, followed by wrong dose and wrong quantity or wrong diluent. Unlike commercial drugs, investigational drugs are usually supplied with patient-specific supplies or individual kits to maintain blinding or to prevent dispensing errors, according to the researchers.

“In such a case, a prescription error occurs due to the omission of kit numbers or wrong kit numbers,” they said. “Wrong kit numbers are usually caused by an error in a copy of the previous order or typing error.” [Contemp Clin Trials 2014;38:270-274]