Excipient protectants

The preclinical safety evaluation of a new excipient generally commences after initial in vitro pharmacy work to demonstrate the material s proposed role. Additionally, some in vivo investigations (often a short exposure study in the rodent) may occur, for example, comparing the new proposed material in a drug formulation versus a marketed drug formulation. Enhanced drug exposure and/or a reduced toxicity profile (through the use of lower-dose levels or excipient protection) may be a study end point. 

Guggi D, Bernkop-Schnurch A (2003) In vitro evaluation of polymeric excipients protecting calcitonin against degradation by intestinal serine proteases. Int J Pharm 252 187-196 Guggi D, Krauland AH, Bernkop-Schnurch A (2003) Systemic peptide delivery via the stomach in vivo evaluation of an oral dosage form for salmon calcitonin. J Control Release 92 125-135... 

The API is likely to be a small component of the tablet. Various other nonpharmacologically active ingredients, called excipients, are also constituents of the tablet. Each of these excipients has a specific characteristic that enables it to perform a useful function in getting the API to its target receptor. Some of the excipients protect the API from various chemical attacks in the mouth and on its way to the gastrointestinal tract. Others help it to travel through the gastrointestinal tract. Eventually the API is released from its formulation so that it can be absorbed in the small intestine and be transported around the body in the blood supply. 

Chem. Descrip. Sodium carboxymethyl cellulose CAS 9004-32-4 EINECS/ELINCS 265-995-8 Uses Thickener, binder, stabilizer, excipient, protective colloid, suspending agent for foods, cosmetic and pharmaceutical ointments, and paints CN 104 [Sartomer]... 

For thousands of years, nature has provided humankind with a large variety of materials for the most diversified applications for its survival, such as food, energy, medicinal products, protection and defense tools, and others. The pharmaceutical industry has benefitted from such diversity of biomaterials and has exploited the use of natural products as sources of both drugs and excipients. One example of a promising biomaterial for pharmaceutical use is xylan, a hemicellulose largely found in nature, being considered the second most abundant polysaccharide after cellulose. 

The FDA has proved to be responsive to criticism, probably more so than many other federal agencies. To give one example, in 1989 it took roughly 33 months for a market approval letter to be issued from the date of request 10 years later this dropped to 13 months. Issues still remain, however. No new drug excipients had been approved in over 20 years because no manufacturer was willing to spend the money on the extensive toxicity testing required without commercial exclusivity or protection. 

Inhalation solution and suspension drug products are typically aqueous-based formulations that contain therapeutically active ingredients and can also contain additional excipients. Aqueous-based oral inhalation solutions and suspension must be sterile (21 CFR 200.51). Inhalation solutions and suspensions are intended for delivery to the lungs by oral inhalation for local or systemic effects and are used with a specified nebulizer. Unit-dose presentation is recommended for these drug products to prevent microbial contamination during use. The container closure system for these drug products consists of the container and closure and can include protective packaging such as foil overwrap. 

The inactive ingredient is used at a level no higher than reasonably required to achieve its physical or technical function. For example, an antimicrobial excipient ingredient could only be used at a level consistent with preservation of the finished product (not at therapeutic levels), and a sunscreen ingredient could only be used at levels that protected the product from breaking down if the top of the jar was left open, not for protecting the user. 

Stability Residual moisture content—adsorbed moisture on excipient surface protects drug from hydrolytic degradation... 

Enteric coatings are a commonly used class of excipients for delaying the release of drug from dosage forms until the dosage forms reach the small intestine. Enteric coatings are useful for protection of drugs that are labile to acidic environment in... 

---