Cold chains are specially designed distribution networks in which product temperature is controlled and monitored from end to end. Many types of products are distributed using cold chains, including produce, frozen foods, specialty chemicals, and the focus of this article, pharmaceuticals.
Vaccines, for example, are distributed via a pharmaceutical cold chain. Depending on their type, most vaccines must be held between 2 and 8 °C (“refrigerated”) or between -15 and -50 °C (“frozen”) at all times to maintain potency. In recent years, the requirements for pharmaceutical cold chains have become even more demanding, due to the development of drugs that are more sensitive to temperature extremes, like biologics, large molecules, and chemical mixtures. mRNA-based COVID-19 vaccines are an example of this trend.
The development of more complex and sensitive pharmaceuticals also means that cold chain operations will be an area of growth in the coming years. In this article, we’ll discuss how the pharmaceutical cold chain is integrated with pharmaceutical and healthcare operations, how it is maintained and monitored, and what products are commonly distributed using cold chains.
Maintaining the Cold Chain
The pharmaceutical cold chain is a set of integrated equipment and procedures used to maintain the temperature of a pharmaceutical product from the point of manufacture until it is passed on or administered to the patient. The purpose of the cold chain is to maintain sensitive drugs within safe temperature windows to prevent degradation and prolong their usable lifespan.
The equipment side of the cold chain includes refrigerated shipping containers and warehouses, medical-grade freezers and refrigerators, insulated boxes, passive cooling systems like dry ice or phase change materials, and temperature monitoring devices and software.
The procedure side includes things like planning activities, training, scheduling, SOPs, and response checklists for temperature excursions. For a cold chain strategy to be successful and efficient, the procedures and equipment must be fully integrated with one another.
In highly regulated industries, such as those monitored by the FDA, it is also important that procedures are fully documented. In this way, the pharmaceutical cold chain is a part of Good Distribution Practices (GDP), a closely related extension of cGMP processes used in pharmaceutical manufacturing.
The Role of Environmental Monitoring
Environmental monitoring plays a central part in maintaining the cold chain. When operations are running smoothly, monitoring equipment provides records that establish that shipments were held within safe temperature ranges at all times. These records can then be passed on and inspected by customers, regulators, and other stakeholders.
When there is a problem that leads to a temperature excursion, a well-designed monitoring system can quickly alert response personnel so that the issue can be corrected quickly, for example by sounding audible alerts or sending targeted messages by SMS text, phone call, or email. While this is happening, the system collects a detailed, complete record of the temperature excursion, which can be used to make well-informed decisions about product quarantining and final disposition.
Environmental monitoring can also be used to proactively prevent excursions. For example, regular reviews of monitoring data can help to identify trends that would indicate an impending equipment failure or highlight gaps or errors in an SOP.
Maintaining the pharmaceutical cold chain means controlling and monitoring temperature (and sometimes humidity) at every point during shipment and distribution. That can require several types of monitoring equipment, like stationary data loggers in temperature-controlled warehouses and loading docks, and package-level monitors that travel with the shipment, like Bluetooth-enabled sensors and individual vial monitors.
Modern environmental monitoring hardware can be used in combination with cloud-based software tools, allowing real-time remote data access, and the potential to integrate many monitoring points into a single dashboard.
Cold Chains as Part of Pharmaceutical and Healthcare Logistics
Maintaining the integrity of cold chains is critical to the safety of the US pharmaceutical supply. For this reason, cold chain procedures for pharmaceuticals are established in federal law, as parts of 21 CFR 203, 205, and 211. Temperature monitoring for prescription drug distribution is specifically addressed in 21 CFR 205.50, which outlines the need for temperature and humidity recording equipment, as well as requirements for comprehensive record keeping. These rules are actively enforced by the FDA, which can flag potential cold chain violations uncovered during audits in Form 483 observations.
The FDA also monitors and enforces cold chains for perishable and frozen foods, through the Food Safety Modernization Act.
The pharmaceutical cold chain is maintained all the way through administration or transfer to the patient. This means that storage and handling of temperature-sensitive drugs at healthcare facilities and pharmacies represent the final step in the cold chain. At this point, it becomes the responsibility of facility operations, as well as pharmacists, nurses, and other clinicians.
Here again, vaccines provide a good example of how cold chain logistics extend to healthcare facilities. This is exemplified by the procedures outlined in the CDC’s detailed vaccine storage and handling toolkit for healthcare providers. The toolkit discusses relevant logistical issues that apply not only to vaccines but the last step for any cold chain pharmaceutical, including:
- Refrigeration equipment selection, setup, and maintenance
- Temperature monitoring devices
- Organization of refrigerated stock within temperature-controlled spaces
- Inventory management
- Response procedures for temperature excursions
- Emergency transport between facilities
- Staff training
- Other personnel considerations, such as defining a single coordinator for cold chain management at the facility
- Record keeping and data review
Cold Chain Products
In addition to vaccines, a wide variety of products are distributed via cold chains, including:
- Other temperature-sensitive pharmaceuticals like biologics, interferons, monoclonal antibodies, and oncology medicines. (Refer to drug labels for specific storage requirements.)
- Some medical test kits
- Biological specimens, such as tissue samples
- Blood products, including whole blood, packed red blood cells, plasma, and others
- Frozen and other perishable foods including produce
- Certain specialty chemicals
As we discussed earlier, the distribution of pharmaceuticals, medical devices, and food products is regulated and audited by the federal government. However, there is a growing trend to extend cold chain logistics to other products that aren’t regulated, to lengthen shelf lives and extend the reach of distribution networks.
The pharmaceutical cold chain is the set of equipment and procedures used to maintain refrigeration of sensitive products during shipping and distribution. Robust cold chain operations are key to maintaining a safe pharmaceutical supply, and because of this, cold chain regulations are enforced by the FDA.
The last step of the cold chain involves storage and handling at pharmacies and healthcare facilities. Using a modern, automated environmental monitoring system can optimize reliability and remove unnecessary burdens from clinicians by providing remote data access and custom alarms.
Questions about implementing a cold chain environmental monitoring system? Contact the experts at Dickson.