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Generic Femring Availability

Femring is a brand name of estradiol, approved by the FDA in the following formulation(s):

FEMRING (estradiol acetate - insert, extended release;vaginal)

  • Manufacturer: APIL
    Approval date: March 20, 2003
    Strength(s): EQ 0.05MG BASE/24HR, EQ 0.1MG BASE/24HR [RLD]

Has a generic version of Femring been approved?

No. There is currently no therapeutically equivalent version of Femring available in the United States.

Note: Fraudulent online pharmacies may attempt to sell an illegal generic version of Femring. These medications may be counterfeit and potentially unsafe. If you purchase medications online, be sure you are buying from a reputable and valid online pharmacy. Ask your health care provider for advice if you are unsure about the online purchase of any medication.

See also: About generic drugs.

Related Patents

Patents are granted by the U.S. Patent and Trademark Office at any time during a drug's development and may include a wide range of claims.

  • Intravaginal drug delivery devices for the administration of 17.beta.-oestradiol precursors
    Patent 5,855,906
    Issued: January 5, 1999
    Inventor(s): McClay; Allen
    Assignee(s): Galen (Chemicals) Limited
    The invention relates to an intravaginal drug delivery device for administration to a female mammal of certain 17.beta.-oestradiol precursors at a substantially constant rate for a period of at least three weeks. The 17.beta.-oestradiol precursor is a 17.beta.-oestradiol moiety in which the, or each, hydroxyl group of the 17.beta.-oestradiol moiety is blocked by a blocking group, which blocking group is readily removed from the 17.beta.-oestradiol in vivo. The 17.beta.-oestradiol precursor must have either a solubility in liquid silicone of not less than 0.1 mg/100 ml or a standard k value of not less than 0.1 .mu.g/day/mm. The 17.beta.-oestradiol precursor must also have a solubility in distilled water of not less than 1 .mu.g/100 ml.
    Patent expiration dates:
    • December 19, 2015


Drug PatentA drug patent is assigned by the U.S. Patent and Trademark Office and assigns exclusive legal right to the patent holder to protect the proprietary chemical formulation. The patent assigns exclusive legal right to the inventor or patent holder, and may include entities such as the drug brand name, trademark, product dosage form, ingredient formulation, or manufacturing process A patent usually expires 20 years from the date of filing, but can be variable based on many factors, including development of new formulations of the original chemical, and patent infringement litigation.
Drug ExclusivityExclusivity is the sole marketing rights granted by the FDA to a manufacturer upon the approval of a drug and may run simultaneously with a patent. Exclusivity periods can run from 180 days to seven years depending upon the circumstance of the exclusivity grant.
RLDA Reference Listed Drug (RLD) is an approved drug product to which new generic versions are compared to show that they are bioequivalent. A drug company seeking approval to market a generic equivalent must refer to the Reference Listed Drug in its Abbreviated New Drug Application (ANDA). By designating a single reference listed drug as the standard to which all generic versions must be shown to be bioequivalent, FDA hopes to avoid possible significant variations among generic drugs and their brand name counterpart.