Pharmaceutical drugs have seen a seismic shift over the past ten years, moving away from chemically synthesised drugs to focus more on a new class of biological drugs (biologics).
Biologics have the potential to revolutionise the treatment of many common conditions that significantly affect millions of lives, such as rheumatoid arthritis, diabetes, autoimmune diseases and certain cancers. Nearly 50% of the new FDA-approved drugs have been biologics, showing the size of the shift.
Yet, biologics are, by nature, more fragile. To facilitate the mass adoption of these new biological drugs, the industry needs to find safe, effective and cost-efficient ways to deliver them.
Challenges with Delivering Biological Drugs
The previous generation of chemically synthesised drugs is pretty much one-size-fits-all. Drugs like paracetamol work for the majority of people in safe doses, they come in stable pill form, and it is difficult to accidentally overdose. Overall, they are safe to self-administer, relatively effective and cheap to produce, transport and sell.
Biological drugs, on the other hand, are very different in terms of properties and formulations. They are much more complicated, specific and targeted, meaning greater efficacy and fewer side effects. Yet, this also means they tend to be more vulnerable and more potent. A large set of biological drugs are delivered through the parenteral route in the form of injections. However, this presents issues such as a risk of infection, needle stick injuries and adherence. Major adversity includes vascular damage, injury to the nerve, tissue necrosis and muscle fibrosis.
Most biological drugs need to be stored in refrigerated units at exact temperature ranges to keep them stable. They also need to be administered in very specific doses, tailored to the individual and usually injected intravenously. As such, they tend to be stored, handled and administered in hospitals, health centres, and GP surgeries, complicating the delivery of these medications. Not only does this make it much more expensive to deliver these biological drugs but it also makes it harder to transport and store, especially in countries without reliable refrigeration or power, making the global adoption of these drugs much more difficult.
The complex nature of biologics structure presents the formulation scientist with a unique set of challenges. Biologics can be easily altered during the formulation process, storage, environmental conditions, and administration causing denaturation and degradation, resulting in the loss of some or all of the therapeutic efficacy. As such, these challenges lead to complex manufacturing processes and any deviation can significantly impact the potential adverse effects associated with the use of these biologics.
Delivery of biological drugs via the non-parenteral route will circumvent some of the major challenges associated with synthesis, storage and delivery. Any non-parenteral route is likely to address a significant subset of current challenges – it could improve patient compliance through self-administration, reduce the cost of treatment if delivered in a non-specialist facility and/ or at home, improve storage conditions and eliminate the need to freeze or refrigerate the formulation. However, delivery of biologicals through a non-parenteral route requires careful consideration of drug properties, manufacturing methods and route of delivery.
