Enabling Selective Drug Delivery with Enteric Empty Capsules

In healthcare, medicines are important chemical compounds that help cure, prevent, or halt diseases. Since they were first introduced, medicines have helped doctors and physicians cure illnesses and save lives. These days, medicines come from a variety of sources and patients may require them to take in specific dosages or forms. Also, they must usually reach the intended site of action to achieve the required therapeutic effect.

Enteric coated tablets are medications that come with specialized coatings to promote targeted absorption of drugs. In this blog, we explain to you the basics and working mechanisms of enteric empty capsules. Also, we detail the applications of these drugs and the latest advancements in the realm of enteric empty capsules. Read on!

What are Enteric Empty Capsules?

An enteric empty capsule is a specialized capsule with a protective coating that allows it to pass through the stomach before being absorbed by the body. It comes with an enteric material to resist the acidic condition of the stomach. Enteric empty capsules are highly useful for substances that can be degraded by the highly acidic conditions of the gastric environment or for those that must be released in the intestines for better absorption. These capsules are typically made from gelatin, which finds applications in herbal products, immune health supplements, and OTC drugs.

Working Mechanism of Enteric Empty Capsules

Enteric empty capsules are designed to protect the ingredients from the stomach’s highly acidic environment and release them in a more neutral environment. The key aspects of its working mechanism are:

Acid-resistant Coating: Enteric empty capsules come with a polymer-based enteric coating that’s insoluble and stable in the stomach’s acidic pH. The coating helps prevent the capsule from disintegrating and releasing the ingredients prematurely.

pH-dependent Release: The pH levels of the small intestine are higher than the pH levels of the stomach. As the enteric capsule makes its way from the stomach to the small intestine, its rapid dissolving takes place. That way, the capsule releases its content in a more neutral environment.

Selective Drug Delivery: The enteric coating ensures that sensitive drugs are protected from the harsh gastric environment and are instead delivered to the intended action site in the small intestine. This is highly useful for unstable drugs or pharmaceuticals that may cause irritation in the stomach lining.

Targeted Drug Absorption: Enteric capsules promote the optimal absorption of drugs by releasing them in the small intestine.

In essence, enteric capsules enable the targeted and controlled release of the capsule contents. This mechanism helps ensure the effectiveness and stability of sensitive drug formulations.

Examples of Enteric Coated Drugs

Here are some examples of drugs that need to be protected from stomach acid:

Erythromycin: Erythromycin is an antibiotic used in the treatment of bacterial infections. It’s used to treat skin infections, respiratory tract infections, and pelvic inflammatory disease. Being an antibiotic, erythromycin comes as a delayed-released medication. It contains enteric-coated pellets that go from the stomach to the small intestine to be absorbed.

Pancrelipase: Pancrelipase is an enzyme that’s given to support digestion when the pancreas isn’t functioning properly. It comes as a delayed-release capsule that contains enteric-coated spheres. The coating prevents the ingredients from causing irritation in the mouth and helps the medication reach the small intestine. Pancrelipase products go by several brand names, including Viokace, Creon, Zenpep and Pertyze.

Proton Pump Inhibitors: Proton Pump Inhibitors (PPIs) are medications that help reduce the production of stomach acid to treat conditions such as stomach ulcers and acid reflux. They work by irreversibly inhibiting the stomach's H?/K? ATPase proton pump. Some PPIs are available over the counter, whereas others need a prescription. Some common enteric-coated PPIs include Protonix, Aciphex, Prilosec, Nexium, and Prevacid.

Entocort EC: Entocort is a capsule used to treat a certain bowel condition (Crohn's disease), which leads to inflammation in the small intestine. The capsule comes with enteric-coated granules that dissolve when the pH levels are higher than 5.5. That way, the capsule can reach the small intestine and reduce swelling.

Applications of Enteric Empty Capsules

Enteric empty capsules are specialized empty capsules used for a wide variety of applications. Some of them include:

Protecting Acid-Sensitive Ingredients

The acidic content in the stomach is high. As such, probiotics and other sensitive substances may get degraded or inactivated in the stomach. Enteric capsules provide a reliable option to protect these ingredients and ensure they get delivered to the intended site of action.

Fecal Microbiota Transplant (FMT)

Fecal microbiota transplant, also referred to as stool transplant, is the administration of fecal matter from a healthy individual to another individual. In FMT, enteric capsules are often used to encapsulate the frozen fecal material. Also, it enables the delivery of fecal matter to the intestine, where it can help restore a healthy gut microbiome.

Targeted Intestinal Delivery

As mentioned earlier, enteric capsules can bypass the stomach and deliver the content directly to the small intestine. This is particularly useful for drugs that are best absorbed in the intestines.

Latest Advancements in Enteric Empty Capsules

Here are some of the most recent developments driving innovation in enteric empty capsules:

• In June 2024, Lonza Group Ltd. announced the launch of Capsugel Enprotect. It comes with a size nine capsule that is designed to protect drugs against stomach acid. The drug is primarily targeted at pre-clinical rodent testing and can speed up the drug evaluation process.
• In October 2023, Evonik Industries introduced a new functional oral capsule for clinical studies. The introduction of the new oral capsule will add a 9h enteric-coated capsule to its range. Also, it will ease the shift from pre-clinical to first-in-human studies.

Promoting Better Drug Absorption

To conclude, enteric empty capsules are widely used in the development of oral medications to protect them from the stomach’s acidic conditions. They help mask unpleasant tastes and promote better absorption. Also, they tend to act faster as compared to other capsules. Furthermore, enteric empty capsules take one or two hours to dissolve, making them apt for time-sensitive medications.