VIAGRA (sildenafil – tablet; oral)
- Manufacturer: PFIZER IRELAND
Approval date: March 27, 1998
Strength(s): EQ 100MG BASE [RLD], EQ 25MG BASE, EQ 50MG BASE
Has a generic version of Viagra been approved?
No. There is currently no therapeutically equivalent version of Viagra available.
Note: Fraudulent online pharmacies may attempt to sell an illegal generic version of Viagra. These medications could be counterfeit and potentially unsafe. If you decide on medications online, make sure to are buying originating from a reputable and valid online pharmacy. Ask your medical provider for advice if you’re unsure regarding the online purchase of any medication.
See also: About generic drugs.
Patents are granted by the U.S. Patent and Trademark Office anytime during a drug’s development and might your website wide range of claims.
- Pyrazolopyrimidinone antianginal agents
Issued: October 5, 1993
Inventor(s): Bell; Andrew S. & Brown; David & Terrett; Nicholas K.
Assignee(s): Pfizer Inc.
Compounds with the formula: ##STR1## wherein R.sup.1 is H, C.sub.1 -C.sub.3 alkyl, C.sub.3 -C.sub.5 cycloalkyl or C.sub.1 -C.sub.3 perfluoroalkyl; R.sup.2 is H, C.sub.1 -C.sub.6 alkyl optionally substituted by OH, C.sub.1 -C.sub.3 alkoxy or C.sub.3 -C.sub.6 cycloalkyl, or C.sub.1 -C.sub.3 perfluoroalkyl; R.sup.3 is C.sub.1 -C.sub.6 alkyl, C.sub.3 -C.sub.6 alkenyl, C.sub.3 -C.sub.6 alkynyl, C.sub.3 -C.sub.7 cycloalkyl, C.sub.1 -C.sub.6 perfluoroalkyl or (C.sub.3 -C.sub.6 cycloalkyl)C.sub.1 -C.sub.6 alkyl; R.sup.4 taken plus the nitrogen atom that it is attached completes a pyrrolidinyl, piperidino, morpholino, or 4-N-(R.sup.6)-piperazinyl group; R.sup.5 is H, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.3 alkoxy, NR.sup.7 R.sup.8, or CONR.sup.7 R.sup.8 ; R.sup.6 is H, C.sub.1 -C.sub.6 alkyl, (C.sub.1 -C.sub.3 alkoxy) C.sub.2 – C.sub.6 alkyl, hydroxy C.sub.2 -C.sub.6 alkyl, (R.sup.7 R.sup.8 N)C.sub.2 -C.sub.6 alkyl, (R.sup.7 R.sup.8 NCO)C.sub.1 -C.sub.6 alkyl, CONR.sup.7 R.sup.8, CSNR.sup.7 R.sup.8 or C(NH)NR.sup.7 R.sup.8 ; R.sup.7 and R.sup.8 are each independently H, C.sub.1 -C.sub.4 alkyl, (C.sub.1 -C.sub.3 alkoxy)C.sub.2 -C.sub.4 alkyl or hydroxy C.sub.2 -C.sub.4 alkyl; and pharmaceutically acceptable salts thereof, are selective cGMP PDE inhibitors valuable in treating cardiovascular disorders such as angina, hypertension, coronary failure and atherosclerosis.Patent expiration dates:
- September 27, 2012
- September 27, 2012
- Pyrazolopyrimidinones to the management of impotence
Issued: October 22, 2002
Inventor(s): Peter; Ellis & Nicholas Kenneth; Terrett
Assignee(s): Pfizer Inc
Using a compound of formula (I) wherein R1 is H; C1-C3 alkyl; C1-C3 perfluoroalkyl; or C3-C5 cycloalkyl; R2 is H; optionally substituted C1-C6 alkyl; C1-C3 perfluoroalkyl; or C3-C6 cycloalkyl; R3 is optionally substituted C1-C6 alkyl; C1-C6 perfluoroalkyl; C3-C5 cycloalkyl; C3-C6 alkenyl; or C3-C6 alkynyl; R4 is optionally substituted C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkanoyl, (hydroxy)C2-C4 alkyl or (C2-C3 alkoxy)C1-C2 alkyl; CONR5R6; CO2R7; halo; NR5R6; NHSO2NR5R6; NHSO2R8; SO2NR9R10; or phenyl, pyridyl, pyrimidinyl, imidazolyl, oxazolyl, thiazolyl, thienyl or triazolyl any of and that is optionally substituted with methyl; R5 and R6 are each independently H or C1-C4 alkyl, or alongside the nitrogen atom to which these are attached form an optionally substituted pyrrolidinyl, piperidino, morpholino, 4-N(R11)-piperazinyl or imidazolyl group; R7 is H or C1-C4 alkyl; R8 is optionally substituted C1-C3 alkyl; R9 and R10 along with the nitrogen atom to which they can be attached form an optionally substituted pyrrolidinyl, piperidino, morpholino or 4-N(R12)-piperazinyl group; R11 is H; optionally substituted C1-C3 alkyl; (hydroxy)C2-C3 alkyl; or C1-C4 alkanoyl; R12 is H; optionally substituted C1-C6 alkyl; CONR13R14; CSNR13R14; or C(NH)NR13R14; and R?13? and R14 are each independently H; C1-C4 alkyl; or substituted C2-C4 alkyl; or possibly a pharmaceutically acceptable salt thereof, or possibly a pharmaceutical composition containing either entity, for your output of a medicament for your curative or prophylactic treatments for erectile dysfunction inside a male animal, including man; a pharmaceutical composition for said treatment; plus a means of said treatments for said male animal with said pharmaceutical composition or with said either entity.Patent expiration dates:
- October 22, 2019
- April 22, 2020