The difficulties of handling Overage in Clinical Trial Supply

16th February 2016 (Last Updated February 16th, 2016 11:54)

CTA takes a look at why overage is huge a problem facing the supply chain

One of the most pressing issues facing the clinical supply chain is forecasting and demand planning, ensuring there are enough supplies in place as a clinical trial gets underway. For a start, there are numerous variables to consider (patient recruitment, clinical supplies, etc.) that, if the forecast isn't accurate or doesn't account for unexpected changes, could delay or disrupt a study.

Typically, supply chain experts would use historical data from previous trials to gauge and estimate what was likely needed in a new trial. Variables such as patient enrolment, clinical supplies, and the number of sites (located potentially in various places around the world) are normally assessed.

Nevertheless, experts say using that approach to guess what is needed is not without its faults. For instance, assessing the number of drugs needed mean that any change that may occur in the study design is difficult to account for or predict. Then there is the added problem of managing your overage (or underage) of clinical supplies, which one expert told CTA is growing problem within the clinical supply chain. Ensuring there are enough drugs in a study is one of most challenging aspects to demand planning. The difficulty in predicting patient enrolment in the forecast phase means supply chain managers oversupply drugs to avoid stock out.

But let's take a step back. For those not involved in clinical supply, what does 'overage' mean? Overage, in supply chain terms, is when you have a surplus of clinical supplies thus reducing the risk of a stock out.

"The problem with overage is that it's a flawed approach to demand planning," said one clinical supply expert. "And that's for several reasons. First off, you're not planning to a controlled target, all you're doing is throwing inventory into the system with no specific rhyme or reason and no control over it."

According to this expert, there is seemingly no proper inventory management across the board, and that is the crux of the matter.

"To site an example, say, you have 10 patients coming into a study over a one year period. Imagine you need 10 doses, one for each patient, so you ship 10 doses meaning you have an overage of zero percent. But if instead 20 doses are shipped, you have an overage of 100 percent, so each patient potentially gets two doses. The problem with that is (instead of 10 patients) what happens when more patients begin to enrol and you run out of drugs?"

The key to addressing this problem is in improving how the inventory is managed. So what is the best way to manage your inventory to minimise the threat of overage?

In the past, much has been written on this topic. Popular opinion among clinical supply professionals is that the use of Interactive Voice Response (IVR) systems is one way to address this problem. IVR systems can reduce by accurately forecasting and targeting available supplies and distributing them to sites that enrolling and retaining patients. But while IVR may alleviate some of these issues, it is by no means the panacea.