Demand forecasting in a pandemic: New considerations from EMA

A new reflection paper from an EU steering group on drug shortages provides considerations for forecasting demand for medicines in the face of global health emergencies.
 
“The methodology is based on pragmatic predictions of demand for certain medicines and encourages the use of the best available information, with an aim to reach the right balance between existing uncertainties with regards to the actual future demand, and the imperative public health need to prepare for a potential major increase in demand,” wrote the European Medicines Agency (EMA) in a press release announcing the availability of the reflection paper.
 
Experts from EMA, the European Commission (EC) and national competent authorities came together for the ad hoc working group that developed the reflection paper, which includes examples and considerations specific to the current global health emergency of the COVID-19 pandemic. However, “many of the general principles are applicable to other emergencies which require to forecast demand for medicines,” wrote EMA.
 
Although the aim of the reflection paper is to guide forecasting on the national level, it also seeks to facilitate a harmonized EU-wide approach. Since demand forecasting is meant to guide medicine manufacturing, the reflection paper recommends that a demand forecast look at least 6 months ahead.  
 
Forecasting should use an epidemiological model for the likely course of an epidemic or a pandemic, but factors affecting the course of the emergency may differ among Member states. For COVID-19, response strategies, including non-pharmaceutical interventions such as stay-at-home orders, differ from state to state. Seasonality, protective immunity, and re-importation of the pathogen are among other factors to take into consideration, according to the reflection paper.
 
Mathematical modeling “allows the robust quantification of uncertainty alongside such predictions,” note the authors of the paper. Forecasting a best- and worst-case scenario, as well as projecting what the most likely situation will be, can allow policy decisions that account for a variety of possibilities. In addition to a mathematical approach, historic data can also be used to forecast needs. In all cases, one important factor in reaching the demand forecast is the maximum capacity of intensive care unit (ICU) beds in each member state.
 
The reflection paper recommends that a variety of different indicators be folded into demand forecasting, including the number of new confirmed cases, new hospital admissions, total hospitalizations, ICU beds, and number of ventilated patients. Other factors, such as average hospital length of stay, may vary from country to country, notes the paper.
 
The paper gives guidelines about how to identify the best available data source for forecasting; ongoing work by the EC’s Joint Research Center (JRC). That center has developed an online tool to generate various scenarios that can be used by all member states. Data from such a harmonized EU-wide model are preferred over national epidemiological data and such other methodologies as extrapolation.
 
Data elements to use when forecasting demand are also covered in the reflection paper; these include patient need, ICU occupancy, medicine use within and outside the ICU setting, needs for other medicines not pertaining to the pandemic and supply chain and stock factors. The paper provides specifics within each of these categories and provides methods for weighting and calculation of the various data elements.
 
Reflection paper