pending patent applications. Moreover, we may have to participate
in interference proceedings declared by the U.S. Patent and
Trademark Office, USPTO, to determine priority of invention, or in
post-grant challenge proceedings in the USPTO or foreign patent
offices such as oppositions, reexamination, inter-partes review,
post grant review, or a derivation proceeding, that challenge our
entitlement to an invention or the patentability of one or more
claims in our patent applications or issued patents. Such
proceedings could result in substantial cost, even if the eventual
outcome is favorable to us.
More specifically, Twirla is a transdermal contraceptive hormone
delivery system. The system is a patch for application to the skin
and contains two API, the hormones LNG, which is a synthetic
progestin, and EE, a synthetic estrogen. The API are formulated
with a combination of skin penetration enhancers, which promote
penetration through the dermis and into the bloodstream, such that
effective blood levels of the active agents are achieved to
suppress ovulation and thereby prevent pregnancy.
In our Twirla product candidate line the active adhesive system
consists of the active ingredients in a polyacrylate adhesive
polymer matrix comprising the permeation enhancers
dimethylsulfoxide, ethyl lactate, capric acid and lauryl lactate.
The active blend is coated onto a release liner, and a backing
layer is added on top of the active blend. The peripheral adhesive
system comprising three layers, also called the overlay, is added
onto the backing layer. The overlay comprises a polyisobutylene
adhesive layer, an acrylic adhesive layer, and an overlay covering.
The overlay covering is a commercially available silk-like
polyester fabric. The adhesive components of the overlay, in
addition to their adhesive function, create an in situ seal with the disposable release
liner, trapping evaporable solvents in the active blend, thereby
extending the usable shelf life of the product candidate and
contributing to the comfort and effectiveness of the transdermal
system during use. Prior to use of any of our potential product
candidates, the release liner is removed by the user and discarded.
The patch is then applied to the skin.
Three U.S. patents are listed
in the FDA’s Orange Book. Five other previously-listed U.S. patents
have now expired. Of those expired U.S. Patents, foreign
counterparts have been granted and remain in force in China, Hong
Kong, India, Israel and Mexico. Those patents are directed to the
dried final product formulation used in Twirla and to methods of
administration.
U.S. Patent Nos. 8,246,978, 8,747,888, and 9,050,348,
currently listed in the Orange Book, are directed to structural
features of the transdermal delivery system used in Twirla patch
design for transdermal delivery of hormones or of other drugs. As
such, these patents protect a platform technology for delivery of
LNG, EE, other hormones, and other drugs. These patents expire in
July and August 2028. Foreign counterparts have been granted in
Australia, Brazil, Canada, Eurasia, Switzerland, Germany, Spain,
France, United Kingdom, Hong Kong, Ireland, India, Italy, Japan,
Netherlands, New Zealand and Japan.
U.S. Patent Nos. 9,198,876, 9,192,614, 9,198,919, 9,198,920,
9,775,847 and 9,782,419 and related patents and patent applications
are directed to various novel dosing regimens, each of which
employs transdermal delivery of contraceptive doses of EE and LNG
during a “treatment interval” and transdermal delivery of low dose
EE and low dose LNG during a “withdrawal interval”. Foreign
counterparts are granted in Europe and Canada. We expect these
patents will be relevant to two of the products in our pipeline,
AG200-SP and AG200-ER, as well
as other new potential regimens. These patents expire in October
2029.
U.S. Patent No. 9,364,487 is directed to a composition and
device for transdermal delivery of LNG for P-only therapy. The
composition contains an anti-oxidant to protect the progestin against
oxidative degradation caused by other components of the
composition. Foreign counterparts are granted in Canada, Europe,
Hong Kong, India, Japan and Mexico. Though not relevant to any
current pipeline products, these patents may be useful for
protection of future products. These patents expire in November
2032.
We have patent applications pending in the United States and
certain foreign jurisdictions directed to novel formulations and
methods designed to improve efficacy and modulate side effects of
administration, as well as to provide personalized dosing based on
body weight or BMI. We also have a pending United States patent
application directed to packaging for transdermal systems
containing certain skin permeation enhancers.