A saccharide polymer containing a small number (typically three to ten) of monosaccharides (simple sugars).

Open Study

A type of trial where both the participants and the researchers know which type of investigational drug the participant is receiving.

Operational Qualification (OQ)

Establishing confidence that a process equipment and sub-system are capable of consistently operating within stated limits and tolerances

Optic neuritis

A medical condition in which vision deteriorates rapidly over hours or days. One or both eyes may be affected. Optic neuritis results from the damage to the optic nerves, though the cause is unknown in most cases. Patients may regain their vision or be left with permanent impairment.


Inflammation of the testicles, a complication of mumps infection occurring in males who are beyond puberty.

Orphan Drug

A pharmaceutical agent that is developed to treat certain rare medical conditions. An orphan drug would not be profitable to produce without government assistance, due to the small population of patients affected by the conditions.

Otitis Media

A viral or bacterial infection that leads to inflammation of the middle ear. This condition usually occurs along with an upper respiratory infection. Symptoms include earache, high fever, nausea, vomiting, and diarrhea. In addition, hearing loss, facial paralysis, and meningitis can result.


It allows a company (the licensor) to grant another organization (the licensee) the rights to use its product, technology, or intellectual property.


The occurrence of cases of disease in excess of what would normally be expected in a defined community, geographical area, and/or season, but below epidemic numbers.

Outer Membrane Protein Complex (OMPC)

A pore-forming protein that facilitates the passive diffusion of small molecules across the bacterial outer membrane. It is highly immunogenic and was used as carrier protein for Hib-OMPC conjugate vaccine.


Measure of the likelihood of a particular outcome. When specific events are equally likely, odds are calculated as the ratio of the number of events that produce that outcome to the number that do not.

Off Label

Use not listed on the label of FDA-approved medications.