Overview
Enabling drug delivery
OraVescent technology delivers drugs directly through the oral mucosa rather than
in the gastrointestinal tract. Delivery of drugs in this manner reduces exposure
of the drug to the acidic and enzymatic conditions of the gastrointestinal tract,
the first-pass effect of the liver and the time delay of systemic delivery. Transmucosal
drug delivery can result in a greater rate and extent of drug uptake into the systemic
circulation, which may also reduce the dose of drug required to produce a therapeutic
effect.
Technical Notes
Shown to improve rate and extent of absorption of some drugs
The OraVescent tablet, an oral transmucosal delivery system, is intended to be placed
in the oral cavity either sublingually or between the buccal and gingival tissues,
where it is allowed to disintegrate passively over several minutes. In addition
to the benefits of oral transmucosal delivery, the OraVescent technology has been
shown to provide enhanced systemic absorption of some drugs across the mucosal tissue
due to its unique mechanism of action.
The enhanced performance of the OraVescent tablet is thought to be related to dynamic,
localized, transient pH changes that occur over the course of tablet disintegration
and dissolution. As the tablet disintegrates in the oral cavity, a chemical reaction
occurs between acidic and basic components in the tablet after contact with water
in the saliva. This results in the liberation of carbon dioxide and produces a modest
decrease in the pH of the tablet microenvironment. For weakly basic drugs, a lower
pH (below its pKa) favors the ionized form of the drug, accelerating its dissolution.
As a pH-modifying substance present in the tablet (e.g., sodium carbonate) dissolves,
the pH increases. This increase in pH causes the ionized drug to convert predominantly
to the un-ionized form, which can be more permeable to biological tissues and can
result in more rapid absorption.
OraVescent tablets are manufactured by a conventional direct compression manufacturing
process. CIMA LABS offers the PakSolv® technology for use in the manufacture
of OraVescent products. This packaging system forms aluminum foil blisters, gently
places the tablets into the blisters and places a seal on the blister, which protects
the tablets from breakage, light and moisture.
Quick facts:
- Discreet buccal tablet
- Is self-administered and passively disintegrated
- Can be taken anywhere
- Does not require water
- May improve patient compliance
- CO2-generating reaction can enhance the rate and extent of absorption
over other oral transmucosal technologies
- Early systemic exposure
- Lower dose needed for same peak concentration
Case Study
Greater bioavailability and fast pain relief
The FENTORA® product (fentanyl buccal tablet, C-II) is developed with the OraVescent®
drug delivery system. For important information for healthcare professionals and
patients, and for Prescribing Information including the boxed warning on FENTORA,
please visit www.fentora.com.
Reference: B.A-S. Brown, E. Hamed. “OraVescent®
Technology Offers Greater Oral Transmucosal Delivery,” Drug Delivery Technology,
July/August, 2007, (7)7 pp.42-45.