Antares Pharma $AIS Notes re oxybutynin gel patent issues

• I have been promising some follow-up notes on the following passage in the 2010 AIS 10k annual report: "We are aware of two related U.S. patents issued to Watson Pharmaceuticals relating to a gel formulation of oxybutynin (Gelnique®). We believe that we do not infringe these patents and that they should not have been granted. We may seek to invalidate these patents but there can be no assurance that we will prevail. If the patents are determined to be valid and if Anturol® is approved, we may be delayed in our marketing of Anturol® or incur significant expenses defending our patent position which may adversely affect the potential market value of Anturol®"
• Obviously, this issue has serious implications for 1) AIS's ability to partner Anturol in the coming months and 2) the ability to launch and sell Anturol in the market.
• I am by no means a patent expert, so hopefully someone else out there can chime in regarding the relative strength and validity of these Watson Pharma $WPI patents!
• Using the searchable USPTO database, I located 7 patents issued to WPI related to oxybutynin, and will briefly post pertinent info for each of these.
• US patent #6,743,441: "The present invention provides compositions and methods for administering oxybutynin while minimizing the incidence and or severity of adverse drug experiences associated with oxybutynin therapy. In one aspect, these compositions and methods provide a lower plasma concentration of oxybutynin metabolites, such as N-desethyloxybutynin, which is presumed to be contributing at least in part to some of the adverse drug experiences, while maintaining sufficient oxybutynin plasma concentration to benefit a subject with oxybutynin therapy. The invention also provides isomers of oxybutynin and its metabolites that meet these characteristics of minimized incidence and/or severity of adverse drug experiences, and maintenance of beneficial and effective therapy for overactive bladder."...This patent only references transdermal patch, but not gel product. No issue for AIS.
• US patent #7,029,694: "The present invention provides compositions and methods for administering oxybutynin while minimizing the incidence and or severity of adverse drug experiences associated with oxybutynin therapy. In one aspect, these compositions and methods provide a lower plasma concentration of oxybutynin metabolites, such as N-desethyloxybutynin, which is presumed to be contributing at least in part to some of the adverse drug experiences, while maintaining sufficient oxybutynin plasma concentration to benefit a subject with oxybutynin therapy. The invention also provides isomers of oxybutynin and its metabolites that meet these characteristics of minimized incidence and/or severity of adverse drug experiences, and maintenance of beneficial and effective therapy for overactive bladder. In some aspects, the composition may be presented in the form of an unoccluded or free form topically administered gel....What is claimed is: 1. A method of treating with oxybutynin a subject having overactive bladder, while minimizing an anticholinergic or antimuscarinic adverse drug experience associated with said oxybutynin treatment therapy comprising the step of: administering as a topical gel, a composition comprising oxybutynin to a subject to provide a plasma area under the curve (AUC) ratio of oxybutynin to an oxybutynin metabolite of from about 0.5:1 to about 5:1, wherein the topical gel optionally includes a permeation enhancer...."...This is continuation-in-part of the above patent. Filed 11/1/2002, issued 4/18/2006. This is clearly one of the two patents referenced by AIS as a potential impediment to launch of Anturol.
• US patent # 7,081,249: "The present invention provides compositions and methods for administering oxybutynin while minimizing the incidence and or severity of adverse drug experiences associated with oxybutynin therapy. In one aspect, these compositions and methods provide a lower plasma concentration of oxybutynin metabolites, such as N-desethyloxybutynin, which is presumed to be contributing at least in part to some of the adverse drug experiences, while maintaining sufficient oxybutynin plasma concentration to benefit a subject with oxybutynin therapy. The invention also provides isomers of oxybutynin and its metabolites that meet these characteristics of minimized incidence and/or severity of adverse drug experiences, and maintenance of beneficial and effective therapy for overactive bladder."...This patent references only the patch- no issue for AIS.
• US patent #7,081,250: "The present invention provides compositions and methods for administering oxybutynin while minimizing the incidence and or severity of adverse drug experiences associated with oxybutynin therapy. In one aspect, these compositions and methods provide a lower plasma concentration of oxybutynin metabolites, such as N-desethyloxybutynin, which is presumed to be contributing at least in part to some of the adverse drug experiences, while maintaining sufficient oxybutynin plasma concentration to benefit a subject with oxybutynin therapy. The invention also provides isomers of oxybutynin and its metabolites that meet these characteristics of minimized incidence and/or severity of adverse drug experiences, and maintenance of beneficial and effective therapy for overactive bladder."...This patent references only the patch- no issue for AIS.
• US patent #7,081,251: "The present invention provides compositions and methods for administering oxybutynin while minimizing the incidence and or severity of adverse drug experiences associated with oxybutynin therapy. In one aspect, these compositions and methods provide a lower plasma concentration of oxybutynin metabolites, such as N-desethyloxybutynin, which is presumed to be contributing at least in part to some of the adverse drug experiences, while maintaining sufficient oxybutynin plasma concentration to benefit a subject with oxybutynin therapy. The invention also provides isomers of oxybutynin and its metabolites that meet these characteristics of minimized incidence and/or severity of adverse drug experiences, and maintenance of beneficial and effective therapy for overactive bladder"...This patent references only the patch- no issue for AIS.
• US patent #7,081,252: "The present invention provides compositions and methods for administering oxybutynin while minimizing the incidence and or severity of adverse drug experiences associated with oxybutynin therapy. In one aspect, these compositions and methods provide a lower plasma concentration of oxybutynin metabolites, such as N-desethyloxybutynin, which is presumed to be contributing at least in part to some of the adverse drug experiences, while maintaining sufficient oxybutynin plasma concentration to benefit a subject with oxybutynin therapy. The invention also provides isomers of oxybutynin and its metabolites that meet these characteristics of minimized incidence and/or severity of adverse drug experiences, and maintenance of beneficial and effective therapy for overactive bladder."...This patent references only the patch- no issue for AIS.
• US patent #7,087,241: "The present invention provides compositions and methods for administering oxybutynin while minimizing the incidence and or severity of adverse drug experiences associated with oxybutynin therapy. In one aspect, these compositions and methods provide a lower plasma concentration of oxybutynin metabolites, such as N-desethyloxybutynin, which is presumed to be contributing at least in part to some of the adverse drug experiences, while maintaining sufficient oxybutynin plasma concentration to benefit a subject with oxybutynin therapy. The invention also provides isomers of oxybutynin and its metabolites that meet these characteristics of minimized incidence and/or severity of adverse drug experiences, and maintenance of beneficial and effective therapy for overactive bladder."...This patent related to “transmucosal formulation…selected from the group consisting of a buccal tablet, a sublingual tablet, or an adhesive film.”-no issue for AIS.
• US patent #7,179,483: "The present invention provides compositions and methods for administering oxybutynin while minimizing the incidence and or severity of adverse drug experiences associated with oxybutynin therapy. In one aspect, these compositions and methods provide a lower plasma concentration of oxybutynin metabolites, such as N-desethyloxybutynin, which is presumed to be contributing at least in part to some of the adverse drug experiences, while maintaining sufficient oxybutynin plasma concentration to benefit a subject with oxybutynin therapy. The invention also provides isomers of oxybutynin and its metabolites that meet these characteristics of minimized incidence and/or severity of adverse drug experiences, and maintenance of beneficial and effective therapy for overactive bladder. In some aspects, the composition may be presented in the form of an unoccluded or free form topically administered gel...What is claimed is: 1. A method of treating with oxybutynin a subject having overactive bladder, while minimizing an anticholinergic or antimuscarinic adverse drug experience associated with said oxybutynin treatment therapy comprising the step of: administering a transdermal formulation comprising oxybutynin to a subject to provide a plasma area under the curve (AUC) ratio of oxybutynin to an oxybutynin metabolite of from about 0.5:1 to about 5:1, wherein the transdermal formulation optionally includes a permeation enhancer, and wherein the transdermal formulation is in the form of: (a) topical formulation selected from the group consisting of ointments, lotions, gels, pastes, mousses, aerosols and skin creams, or (b) transdermal patches selected from the group consisting of adhesive matrix patches and liquid reservoir systems"...This would appear to be the second of the two patents referenced by AIS as a potential impediment to launch of Anturol.
• US patent #7,921,999: "A peelable pouch comprises a substantially flat enclosure formed by first and second opposing flexible plies. A seal extends along at least a portion of a perimeter of the opposing plies. A flat, flexible transdermal patch is disposed in the enclosure and includes a bioactive agent dissolved in a layer of adhesive. A release liner is removably attached over the layer of adhesive, with the patch and the release liner together being sufficiently resilient so as to generate a spring force when displaced out of the flat configuration. The first and the second plies each being separable along the seal and displaceable out of the flat configuration. The spring force generated by the patch and the release liner being sufficient to overcome an adhesive force created by the adhesive between the patch and one of the plies."...This patent references only the patch- no issue for AIS.